TY - JOUR TI - Intensifying drought eliminates the expected benefits of elevated carbon dioxide for soybean AU - Gray, Sharon B. AU - Dermody, Orla AU - Klein, Stephanie P. AU - Locke, Anna M. AU - McGrath, Justin M. AU - Paul, Rachel E. AU - Rosenthal, David M. AU - Ruiz-Vera, Ursula M. AU - Siebers, Matthew H. AU - Strellner, Reid AU - Ainsworth, Elizabeth A. AU - Bernacchi, Carl J. AU - Long, Stephen P. AU - Ort, Donald R. AU - Leakey, Andrew D. B. T2 - Nature Plants DA - 2016/9/5/ PY - 2016/9/5/ DO - 10.1038/nplants.2016.132 VL - 2 IS - 9 J2 - Nature Plants LA - en OP - SN - 2055-0278 UR - http://dx.doi.org/10.1038/nplants.2016.132 DB - Crossref ER - TY - JOUR TI - Soil phosphorus compounds in integrated crop-livestock systems of subtropical Brazil AU - Deiss, L. AU - Moraes, A. AU - Dieckow, J. AU - Franzluebbers, A.J. AU - Gatiboni, L.C. AU - Sassaki, G.L. AU - Carvalho, P.C.F. T2 - Geoderma AB - Soil phosphorus (P) utilization may be affected by agricultural complexity, in particular when combining annual crops and livestock grazing on the same land area and at overlapping times. Our objectives were to qualify and quantify soil organic and inorganic P compounds using sodium hydroxide-ethylenediaminetetraacetic acid (NaOH-EDTA) extraction and 31P nuclear magnetic resonance spectroscopy (31P NMR) in response to increasing complexity with integrated crop-livestock systems (ICLS) in subtropical Brazil. Soil at a depth of 0–5 cm was collected from three long-term (7 to 12 years) cropping studies with and without ruminant grazing of cover crops. All sites were managed under no tillage, and treatments with livestock were managed with moderate grazing intensity. In these agro-ecosystems, grazing compared with no-grazing had greater soil P content as total and bioavailable orthophosphate and lower soil organic P and fewer monoesters, including inositol phosphates. Grazing increased P bioavailability and reduced recalcitrant organic P concentration in soil; therefore, cropping systems that integrate livestock (ICLS) can be a sustainable alternative to improve P use in farming systems of subtropical Brazil. DA - 2016/// PY - 2016/// DO - 10.1016/j.geoderma.2016.03.028 VL - 274 SP - 88-96 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84962787224&partnerID=MN8TOARS ER - TY - JOUR TI - Cover crops effects on soil chemical properties and onion yield AU - Oliveira, R.A. AU - Brunetto, G. AU - Loss, A. AU - Gatiboni, L.C. AU - Kürtz, C. AU - Müller Júnior, V. AU - Lovato, P.E. AU - Oliveira, B.S. AU - Souza, M. AU - Comin, J.J. T2 - Revista Brasileira de Ciencia do Solo AB - Cover crops contribute to nutrient cycling and may improve soil chemical properties and, consequently, increase crop yield. The aim of this study was to evaluate cover crop residue decomposition and nutrient release, and the effects of these plants on soil chemical properties and on onion (Allium cepa L.) yield in a no-tillage system. The experiment was carried out in an Inceptisol in southern Brazil, where cover crops were sown in April 2012 and 2013. In July 2013, shoots of weeds (WD), black oats (BO), rye (RY), oilseed radish (RD), oilseed radish + black oats (RD + BO), and oilseed radish + rye (RD + RY) were cut at ground level and part of these material from each treatment was placed in litter bags. The litter bags were distributed on the soil surface and were collected at 0, 30, 45, 60, 75, and 90 days after distribution (DAD). The residues in the litter bags were dried, weighed, and ground, and then analyzed to quantify lignin, cellulose, non-structural biomass, total organic carbon (TOC), N, P, K, Ca, and Mg. In November 2012 and 2013, onion crops were harvested to quantify yield, and bulbs were classified according to diameter, and the number of rotted and flowering bulbs was determined. Soil in the 0.00-0.10 m layer was collected for chemical analysis before transplanting and after harvesting onion in December 2012 and 2013. The rye plant residues presented the highest half-life and they released less nutrients until 90 DAD. The great permanence of rye residue was considered a protection to soil surface, the opposite was observed with spontaneous vegetation. The cultivation and addition of dry residue of cover crops increased the onion yield at 2.5 Mg ha-1. DA - 2016/// PY - 2016/// DO - 10.1590/18069657rbcs20150099 VL - 40 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84975801305&partnerID=MN8TOARS ER - TY - JOUR TI - Calibration of phosphorus and potassium fertilization for beet in vale do Itajaí region,Calibração da adubação fosfatada e potássica para beterraba na região do Vale do Itajaí AU - Oliveira, R.J.P. AU - Gatiboni, L.C. AU - Valicheski, R.R. AU - Miquelluti, D.J. AU - Brunetto, G. T2 - Horticultura Brasileira AB - RESUMO: Estudos sobre adubação na cultura de beterraba ainda são necessários em algumas regiões de Santa Catarina. Assim, o objetivo foi avaliar a resposta da cultura da beterraba a doses de fósforo (P) e potássio (K) em Cambissolo Háplico, que é o tipo de solo predominante em 70% da região do Alto Vale do Itajaí. O experimento foi conduzido em Rio do Sul-SC em dois cultivos, sendo o primeiro cultivo instalado em blocos inteiramente casualizados no esquema fatorial 4x4 (0, 200, 400 e 600 kg/ha de P2O5) e (0, 150, 300 e 450 kg/ha de K2O) com 3 repetições. No segundo cultivo, foi avaliada a reposição de P e K, onde cada parcela do primeiro cultivo foi dividida em três, sendo aplicados 0, 33 e 66% das doses iniciais dos nutrientes. Após 60 dias do transplantio foram avaliados diâmetro de raízes, e massa fresca e seca de folhas e raízes. No primeiro cultivo, houve efeito significativo (α= 5%) para o fator P para massa seca e fresca de raiz e diâmetro de raiz e não houve efeito do K, mas a exportação foi elevada, atingindo 172,27 kg/ha de K com a dose 418 kg/ha de K2O. A máxima produção ocorreu com 379 kg/ha de P2O5, sendo que o exportado foi de 21,30 kg/ha de P na massa seca de raízes e folhas. No segundo cultivo, a beterraba respondeu à aplicação de P e K, sendo a máxima produtividade obtida com as maiores doses de P e K (450 kg/ha de K2O e 600 kg/ha de P2O5) e de reposição (300 kg/ha de K2O e 400 kg/ha de P2O5). Conclui-se que a beterraba é uma cultura muito exigente em fertilização com P e K, respondendo a doses maiores do que aquelas recomendadas pelos manuais de adubação utilizados na região. DA - 2016/// PY - 2016/// DO - 10.1590/S0102-053620160000200010 VL - 34 IS - 2 SP - 210-215 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84963516544&partnerID=MN8TOARS ER - TY - JOUR TI - Seed germination of Schinus molle L. (Anacardiaceae) as related to its anatomy and dormancy alleviation AU - Pereira, Marcio P. AU - Correa, Felipe F. AU - Polo, Marcelo AU - Castro, Evaristo M. AU - Cardoso, Amanda A. AU - Pereira, Fabricio J. T2 - Seed Science Research AB - Abstract The seeds of Schinus molle are referred to as displaying physical dormancy because of their water-impermeable endocarp. Therefore, this work aimed to evaluate the germination of S. molle seeds as related to environmental conditions, scarification, storage time and seed anatomy. Various experiments were conducted to test the alleviation of dormancy in newly collected and stored seeds. Acid-scarified seeds incubated under continuous light at 25°C showed greatest vigour and germination. The separation of seeds by specific gravity revealed a higher germination percentage for those seeds that sank. In addition, dry storage alleviated dormancy with a remarkable increase in the various germination parameters. Overall, germination traits decreased after prolonged storage, but even after 12 months the means for germination parameters for stored seeds were still higher than those of newly collected ones. S. molle seeds remain attached to parts of the fruit mesocarp and endocarp. The mesocarp contains several layers of parenchyma showing secretory cavities. The endocarp consists of three layers of sclereids surrounding the embryo. Acid scarification strongly changed the structure of the external layers in the mesocarp, digesting parenchyma cells and removing the contents from both parenchyma cells and the secretory cavities; this improved water uptake during imbibition, which occurred only at the carpellary hilar slit. In conclusion, S. molle seeds are positively photoblastic and show physiological dormancy which can be alleviated by acid scarification and dry storage. Seeds can be stored for over 12 months without significant losses in germination parameters compared to newly collected seeds. DA - 2016/// PY - 2016/// DO - 10.1017/S0960258516000167 VL - 26 IS - 4 SP - 351-361 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84978168285&partnerID=MN8TOARS KW - acid scarification KW - pepper tree KW - photoblastic seeds KW - seed imbibition KW - seed physiology KW - seed structure ER - TY - JOUR TI - Action of nitric oxide in sesame seeds (Sesamum indicum L.) submitted to stress by cadmium,Ação protetora do óxido nítrico em sementes de gergelim (Sesamum indicum L.) submetidas ao estresse por cádmio AU - Oliveira Pires, Raquel Maria AU - Souza, Genaina Aparecida AU - Cardoso, Amanda Avila AU - Santos Dias, Denise Cunha AU - Borges, Eduardo Euclydes T2 - Journal of Seed Science AB - Abstract: The objective of this paper was to evaluate the effect of nitric oxide (NO) as a protecting agent of sesame seeds submitted to different concentrations of cadmium. The treatments were: water (control), water increased by sodium nitroprusside (SNP) and other treatments regarding the concentrations of cadmium increased by SNP. The following determinations were done: germination, first count of germination, germination speed index, length of hypocotyl and radicle and dry matter of hypocotyl and radicle, besides quantification of enzyme activities, superoxide dismutase, catalase, ascorbate peroxidase and total peroxidases. The statistical design was entirely randomized with five replicates. The data was submitted to a variance analysis and the averages obtained for the treatments were compared by the Tukey test at 5% significance. The averages obtained in the treatments with and without SNP were compared by the F test at 5% probability. The NO due to the application of SNP was beneficial, providing an increase in germination, vigor and growth of seedlings. There was a progressive increase of the antioxidant enzymes activity in the period of 0 to 24 hours, showing an organization of the antioxidant system in the sesame seeds throughout germination time. DA - 2016/// PY - 2016/// DO - 10.1590/2317-1545v38n1154824 VL - 38 IS - 1 SP - 22-29 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84962751580&partnerID=MN8TOARS KW - SNP KW - vigor KW - germination KW - antioxidant system ER - TY - JOUR TI - Correction: DNA Sequence Evolution and Rare Homoeologous Conversion in Tetraploid Cotton. AU - Page, JT AU - Liechty, ZS AU - Alexander, RH AU - Clemons, K AU - Hulse-Kemp, AM AU - Ashrafi, H AU - Van, Deynze A AU - Stelly, DM AU - Udall, JA T2 - PLoS genetics AB - [This corrects the article DOI: 10.1371/journal.pgen.1006012.]. DA - 2016/7// PY - 2016/7// DO - 10.1371/journal.pgen.1006206 VL - 12 IS - 7 SP - 1006206, UR - http://europepmc.org/abstract/med/27447832 ER - TY - JOUR TI - DNA Sequence Evolution and Rare Homoeologous Conversion in Tetraploid Cotton. AU - Page, JT AU - Liechty, ZS AU - Alexander, RH AU - Clemons, K AU - Hulse-Kemp, AM AU - Ashrafi, H AU - Van, Deynze A AU - Stelly, DM AU - Udall, JA T2 - PLoS genetics AB - Allotetraploid cotton species are a vital source of spinnable fiber for textiles. The polyploid nature of the cotton genome raises many evolutionary questions as to the relationships between duplicated genomes. We describe the evolution of the cotton genome (SNPs and structural variants) with the greatly improved resolution of 34 deeply re-sequenced genomes. We also explore the evolution of homoeologous regions in the AT- and DT-genomes and especially the phenomenon of conversion between genomes. We did not find any compelling evidence for homoeologous conversion between genomes. These findings are very different from other recent reports of frequent conversion events between genomes. We also identified several distinct regions of the genome that have been introgressed between G. hirsutum and G. barbadense, which presumably resulted from breeding efforts targeting associated beneficial alleles. Finally, the genotypic data resulting from this study provides access to a wealth of diversity sorely needed in the narrow germplasm of cotton cultivars. DA - 2016/5// PY - 2016/5// DO - 10.1371/journal.pgen.1006012 VL - 12 IS - 5 SP - 1006012, UR - http://europepmc.org/abstract/med/27168520 ER - TY - JOUR TI - A HapMap leads to a Capsicum annuum SNP infinium array: a new tool for pepper breeding AU - Hulse-Kemp, Amanda M AU - Ashrafi, Hamid AU - Plieske, Joerg AU - Lemm, Jana AU - Stoffel, Kevin AU - Hill, Theresa AU - Luerssen, Hartmut AU - Pethiyagoda, Charit L AU - Lawley, Cindy T AU - Ganal, Martin W AU - Deynze, Allen Van T2 - Horticulture Research AB - The Capsicum genus (Pepper) is a part of the Solanacae family. It has been important in many cultures worldwide for its key nutritional components and uses as spices, medicines, ornamentals and vegetables. Worldwide population growth is associated with demand for more nutritionally valuable vegetables while contending with decreasing resources and available land. These conditions require increased efficiency in pepper breeding to deal with these imminent challenges. Through resequencing of inbred lines we have completed a valuable haplotype map (HapMap) for the pepper genome based on single-nucleotide polymorphisms (SNP). The identified SNPs were annotated and classified based on their gene annotation in the pepper draft genome sequence and phenotype of the sequenced inbred lines. A selection of one marker per gene model was utilized to create the PepperSNP16K array, which simultaneously genotyped 16 405 SNPs, of which 90.7% were found to be informative. A set of 84 inbred and hybrid lines and a mapping population of 90 interspecific F2 individuals were utilized to validate the array. Diversity analysis of the inbred lines shows a distinct separation of bell versus chile/hot pepper types and separates them into five distinct germplasm groups. The interspecific population created between Tabasco (C. frutescens chile type) and P4 (C. annuum blocky type) produced a linkage map with 5546 markers separated into 1361 bins on twelve 12 linkage groups representing 1392.3 cM. This publically available genotyping platform can be used to rapidly assess a large number of markers in a reproducible high-throughput manner for pepper. As a standardized tool for genetic analyses, the PepperSNP16K can be used worldwide to share findings and analyze QTLs for important traits leading to continued improvement of pepper for consumers. Data and information on the array are available through the Solanaceae Genomics Network. DA - 2016/12/27/ PY - 2016/12/27/ DO - 10.1038/hortres.2016.36 VL - 3 IS - 1 UR - https://doi.org/10.1038/hortres.2016.36 ER - TY - JOUR TI - Manure Injection Affects the Fate of Pirlimycin in Surface Runoff and Soil AU - Kulesza, S. B. AU - Maguire, R. O. AU - Xia, K. AU - Cushman, J. AU - Knowlton, K. AU - Ray, P. T2 - Journal of Environmental Quality AB - Journal of Environmental QualityVolume 45, Issue 4 p. 1466-1466 Erratum Manure Injection Affects the Fate of Pirlimycin in Surface Runoff and Soil S. B. Kulesza, S. B. KuleszaSearch for more papers by this authorR. O. Maguire, Corresponding Author R. O. Maguire kxia@vt.edu Corresponding author (kxia@vt.edu; rmaguire@vt.edu).Search for more papers by this authorK. Xia, Corresponding Author K. Xia rmaguire@vt.edu Corresponding author (kxia@vt.edu; rmaguire@vt.edu).Search for more papers by this authorJ. Cushman, J. CushmanSearch for more papers by this authorK. Knowlton, K. KnowltonSearch for more papers by this authorP. Ray, P. RaySearch for more papers by this author S. B. Kulesza, S. B. KuleszaSearch for more papers by this authorR. O. Maguire, Corresponding Author R. O. Maguire kxia@vt.edu Corresponding author (kxia@vt.edu; rmaguire@vt.edu).Search for more papers by this authorK. Xia, Corresponding Author K. Xia rmaguire@vt.edu Corresponding author (kxia@vt.edu; rmaguire@vt.edu).Search for more papers by this authorJ. Cushman, J. CushmanSearch for more papers by this authorK. Knowlton, K. KnowltonSearch for more papers by this authorP. Ray, P. RaySearch for more papers by this author First published: 01 July 2016 https://doi.org/10.2134/jeq2015.06.0266erCitations: 1 All rights reserved. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume45, Issue4July-August 2016Pages 1466-1466 RelatedInformation DA - 2016/7/1/ PY - 2016/7/1/ DO - 10.2134/jeq2015.06.0266er VL - 45 IS - 4 SP - 1466-1466 ER - TY - JOUR TI - Injecting Poultry Litter into Orchardgrass Hay AU - Kulesza, Stephanie B. AU - Maguire, Rory O. AU - Thomason, Wade E. AU - Pote, Dan H. T2 - Communications in Soil Science and Plant Analysis AB - Traditional surface application of poultry litter leaves nutrients vulnerable to loss through volatilization and runoff. However, injection can increase capture of these nutrients in agricultural fields. Therefore, a field experiment was conducted to determine the effects of poultry litter injection on orchardgrass (Dactylis glomerata L.) hay yield and quality. Poultry litter was injected or surface applied using the Subsurfer poultry litter injector at the recommended agronomic rate (high) and half that rate (low) in 2012 and 2013 in an established field of orchardgrass. Soil was sampled to 15 cm and analyzed for soil nitrate. No significant differences in soil nitrate were detected between treatments. Although not always statistically significant, first cutting orchardgrass yields tended to be greater with surface litter application. Injected treatments had greater protein concentrations than their respective surface treatment, showing greater nitrogen uptake, when protein was weighted by yield. Protein was the same for high surface and low injected treatments showing that similar nitrogen (N) uptake was achieved. DA - 2016/5/4/ PY - 2016/5/4/ DO - 10.1080/00103624.2016.1178761 VL - 47 IS - 11 SP - 1389-1397 KW - Fertility KW - manure injection KW - nutrient management KW - poultry litter ER - TY - SOUND TI - Turfgrass Selection Considerations for NC AU - Miller, Grady DA - 2016/1/13/ PY - 2016/1/13/ ER - TY - SOUND TI - Turfgrass and Plants: Part 2: Landscape Irrigation AU - Miller, Grady DA - 2016/1/12/ PY - 2016/1/12/ ER - TY - SOUND TI - Turfgrass and Plants: Part 1: Water Requirements AU - Miller, Grady DA - 2016/1/12/ PY - 2016/1/12/ ER - TY - SOUND TI - Landscape Irrigation Control to Improve Water Conservation AU - Miller, Grady DA - 2016/11/2/ PY - 2016/11/2/ ER - TY - SOUND TI - Quiz Bowl AU - Miller, Grady DA - 2016/11/15/ PY - 2016/11/15/ ER - TY - SOUND TI - Using turf colorants and pigments for potential long-term color of dormant warm-season grasses AU - Miller, Grady DA - 2016/6/5/ PY - 2016/6/5/ ER - TY - SOUND TI - Colorant Use on Golf Courses AU - Miller, Grady DA - 2016/11/14/ PY - 2016/11/14/ ER - TY - SOUND TI - My turfgrass Teaching, Research, and Extension Program AU - Miller, Grady DA - 2016/10/26/ PY - 2016/10/26/ ER - TY - SOUND TI - Turfgrass Colorant Use AU - Miller, Grady DA - 2016/10/21/ PY - 2016/10/21/ ER - TY - RPRT TI - Carolina Lawns: A Guide to Maintaining Quality Turf in the Landscape AU - Miller, G.L. AU - Peacock, C. AU - Bruneau, A. AU - Yelverton, F. AU - Kearns, J.P. AU - Brandenburg, R. AU - Bowman, D.C. AU - Cooper, R.J. AU - Martin, M. A3 - North Carolina State University Cooperative Extension Service DA - 2016/5/23/ PY - 2016/5/23/ M1 - AG-69 M3 - North Carolina State Extension Publications PB - North Carolina State University Cooperative Extension Service SN - AG-69 ER - TY - SOUND TI - Field Plot Research in Raleigh AU - Miller, Grady DA - 2016/2/18/ PY - 2016/2/18/ ER - TY - SOUND TI - Turf Management in NC Landscapes AU - Miller, Grady DA - 2016/10/6/ PY - 2016/10/6/ ER - TY - SOUND TI - Establishment of Turfgrasses AU - Miller, Grady DA - 2016/2/17/ PY - 2016/2/17/ ER - TY - SOUND TI - My Thanks to the Turfgrass Industry AU - Miller, Grady DA - 2016/2/24/ PY - 2016/2/24/ ER - TY - RPRT TI - Pest control for professional turfgrass managers AU - Brandenburg, R. AU - Butler, L. AU - Gannon, T. AU - Martin, M. AU - Miller, G. AU - Peacock, C. AU - Richardson, R. AU - Warren, L. AU - Yelverton, F. A3 - North Carolina State University Cooperative Extension Service DA - 2016/// PY - 2016/// M1 - AG-408 M3 - NC Cooperative Extension Publications PB - North Carolina State University Cooperative Extension Service SN - AG-408 ER - TY - SOUND TI - Smart Irrigation Control AU - Miller, Grady DA - 2016/10/5/ PY - 2016/10/5/ ER - TY - SOUND TI - Mowing, Aerification, and Other Cultural Practices AU - Miller, Grady DA - 2016/2/17/ PY - 2016/2/17/ ER - TY - MGZN TI - A handy guide to choosing and using turf colorants AU - Miller, G.L. AU - Pinnix, D. T2 - North Carolina Turfgrass DA - 2016/11// PY - 2016/11// SP - 12–17 ER - TY - RPRT TI - 2016 Turfgrass Pest Management Manual AU - Bowman, D.C. AU - Brandenburg, R.L. AU - Gannon, T.W. AU - Kerns, J.P. AU - Peacock, C.H. AU - Richardson, R.J. AU - Rufty, T.W. AU - Warren, L.S. AU - Yelverton, F.H. A3 - North Carolina State University Cooperative Extension Service DA - 2016/6// PY - 2016/6// M1 - AG-348 M3 - NC State Extension Publication PB - North Carolina State University Cooperative Extension Service SN - AG-348 ER - TY - SOUND TI - Sports Turf Research in NC AU - Miller, Grady DA - 2016/9/20/ PY - 2016/9/20/ ER - TY - SOUND TI - Zoysiagrass versus Bermudagrass for the Landscape AU - Miller, Grady DA - 2016/2/5/ PY - 2016/2/5/ ER - TY - JOUR TI - Turfgrass response to field paint AU - Miller, G.L. AU - Pinnix, D. AU - Reynolds, C. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 IS - 10 SP - 16-18 ER - TY - RPRT TI - 2016 Sod Producers’ Report for North Carolina AU - Miller, G.L. A3 - North Carolina State University Cooperative Extension Service DA - 2016/// PY - 2016/// M1 - AG-809 M3 - NC State Extension Publications PB - North Carolina State University Cooperative Extension Service SN - AG-809 ER - TY - SOUND TI - Landscape Irrigation Workshop AU - Miller, Grady DA - 2016/9/16/ PY - 2016/9/16/ ER - TY - SOUND TI - Sports Turf IPM AU - Miller, Grady DA - 2016/2/3/ PY - 2016/2/3/ ER - TY - JOUR TI - Shedding light on athletic field paint and the turfgrass response AU - Miller, G.L. AU - Pinnix, D. AU - Reynolds, C. T2 - Sports Turf Canada DA - 2016/// PY - 2016/// VL - 29 IS - 1 SP - 1, 6–8 ER - TY - SOUND TI - Potassium Fertilization for Fall Turfgrass Management AU - Miller, Grady DA - 2016/8/16/ PY - 2016/8/16/ ER - TY - SOUND TI - Dealing with Winterkill AU - Miller, Grady DA - 2016/2/2/ PY - 2016/2/2/ ER - TY - SOUND TI - Evaluation of Methodologies Estimating Evapotranspiration AU - Miller, Grady AU - Pinnix, Drew DA - 2016/8/10/ PY - 2016/8/10/ ER - TY - MGZN TI - Shedding light on athletic field paint and the turfgrass response AU - Miller, G.L. AU - Pinnix, D. AU - Reynolds, C. T2 - North Carolina Turfgrass DA - 2016/9// PY - 2016/9// SP - 12–14, 15–16 ER - TY - SOUND TI - Warm-season Turfgrass Management in NC AU - Miller, Grady DA - 2016/6/15/ PY - 2016/6/15/ ER - TY - SOUND TI - Cultivar evaluations for golf and sports turf applications AU - Miller, Grady DA - 2016/5/27/ PY - 2016/5/27/ ER - TY - SOUND TI - Effects of Varying Irrigation Regimes Under Simulated Traffic AU - Miller, Grady AU - Pinnix, Drew DA - 2016/8/10/ PY - 2016/8/10/ ER - TY - JOUR TI - Cut quality using a zero-turn mower AU - Miller, G.L. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 IS - 1 SP - 50 ER - TY - SOUND TI - Field Management for High School Coaches AU - Miller, Grady DA - 2016/5/21/ PY - 2016/5/21/ ER - TY - SOUND TI - Speech at NCSU Turfgrass Field Day AU - Miller, Grady DA - 2016/8/10/ PY - 2016/8/10/ ER - TY - SOUND TI - Towards a complete understanding of environmental fate of nitrogen in turfgrass systems AU - Xia, Q. AU - Chen, H. AU - Yang, T. AU - Miller, G. AU - Shi, W. DA - 2016/12/14/ PY - 2016/12/14/ ER - TY - SOUND TI - Sports Turf Management Research AU - Miller, Grady DA - 2016/4/26/ PY - 2016/4/26/ ER - TY - SOUND TI - Evaluation of Fraise Mowing on Soil Properties of Bermudagrass Surfaces AU - Miller, Grady AU - McCauley, Ray DA - 2016/8/10/ PY - 2016/8/10/ ER - TY - SOUND TI - Soil Microorganisms under Turfgrass: the Unseen Engine of Soil Chemical Transformations AU - Xia, Q. AU - Chen, H. AU - Yang, T. AU - Miller, G. AU - Shi, W. DA - 2016/10/20/ PY - 2016/10/20/ ER - TY - SOUND TI - Weed Control Strategies AU - Miller, Grady DA - 2016/3/29/ PY - 2016/3/29/ ER - TY - SOUND TI - Low Input Cool-Season Turf Trial AU - Miller, Grady DA - 2016/8/10/ PY - 2016/8/10/ ER - TY - SOUND TI - Irrigation Requirements of NC Turfgrasses AU - Miller, Grady DA - 2016/5/25/ PY - 2016/5/25/ ER - TY - SOUND TI - Dealing with Stressed-out Turf AU - Miller, Grady DA - 2016/3/15/ PY - 2016/3/15/ ER - TY - SOUND TI - Cultivar evaluations for golf and sports turf applications AU - Miller, Grady DA - 2016/6/19/ PY - 2016/6/19/ ER - TY - SOUND TI - Managing Weeds in NC Turfgrasses AU - Miller, Grady DA - 2016/2/19/ PY - 2016/2/19/ ER - TY - SOUND TI - Irrigation Scheduling for NC Turfgrasses AU - Miller, Grady DA - 2016/10/20/ PY - 2016/10/20/ ER - TY - SOUND TI - Athletic field paint impacts transpiration and canopy temperature in bermudagrass AU - Miller, Grady DA - 2016/11/8/ PY - 2016/11/8/ ER - TY - SOUND TI - Real and Unreal: What is New with Natural and Synthetic Turfgrass AU - Miller, Grady DA - 2016/1/29/ PY - 2016/1/29/ ER - TY - SOUND TI - Influence of Paints and Colorants on Turfgrasses AU - Miller, Grady DA - 2016/12/14/ PY - 2016/12/14/ ER - TY - SOUND TI - Sustainable Turfgrass Care AU - Miller, Grady DA - 2016/1/26/ PY - 2016/1/26/ ER - TY - SOUND TI - Synthetic Turfgrass in the News: Lawsuits and Cancer! AU - Miller, Grady DA - 2016/1/13/ PY - 2016/1/13/ ER - TY - SOUND TI - Sod Production Survey Results AU - Miller, Grady DA - 2016/1/13/ PY - 2016/1/13/ ER - TY - JOUR TI - Not your average garden AU - Miller, G.L. T2 - SportsTurf DA - 2016/9// PY - 2016/9// VL - 32 IS - 9 SP - 50 ER - TY - CHAP TI - Biosynthesis and Assembly of Cellulose AU - Haigler, Candace AU - Davis, Jonathan AU - Slabaugh, Erin AU - Kubicki, James T2 - Molecular Cell Biology of the Growth and Differentiation of Plant Cells PY - 2016/6/7/ DO - 10.1201/b20316-11 SP - 120-138 OP - PB - CRC Press SN - 9781498726023 9781498726030 UR - http://dx.doi.org/10.1201/b20316-11 DB - Crossref ER - TY - JOUR TI - Partitioning Evaporation and Transpiration in a Maize Field Using Heat-Pulse Sensors for Evaporation Measurement T2 - Transactions of the ASABE AB - . Evapotranspiration (ET) is the sum of soil water evaporation (E) and plant transpiration (T). E and T occur simultaneously in many systems with varying levels of importance, yet it is often very challenging to distinguish these fluxes separately in the field. Few studies have measured all three terms (ET, E, and T), and in the few cases where such measurements have been obtained, E is typically determined via destructive lysimetery. For 43 days in a fully developed maize ( L.) field, we continuously measured E using heat-pulse sensors and soil sensible heat balance, T using sap-flow gauges, and ET using an eddy covariance system. Crop evapotranspiration (ETc) was also calculated from the crop coefficient (Kc) and the reference evapotranspiration (ETo), which was determined with the standardized Penman-Monteith equation. During the measurement period, E and T accounted for 13% and 87% of E+T, respectively. E responded to variations in soil moisture and net radiation, whereas T changed primarily with net radiation. All three ET estimation methods (individually measured E+T, eddy covariance ET, and crop ETc) demonstrated similar temporal trends and strong correlations (R2 of 0.76 for ETc vs. E+T and 0.77 for ET vs. E+T), with the values of individually measured E+T close to crop ETc but larger than eddy covariance ET during the measurement period. Disparities in measurements were likely due to variations in measurement scale, which did not reflect the full range of field variability for individually measured E and T, and differences in response to declining soil moisture among the three approaches. Overall, the results support the need for individual measurement of each term (E, T, and ET) when attempting to interpret ET partitioning and suggest that soil heat-pulse sensors provide a viable complement to previously tested approaches for continuously determining E for ET partitioning during wetting-drying periods. DA - 2016/4/21/ PY - 2016/4/21/ DO - 10.13031/trans.59.11059 VL - 59 IS - 2 SP - 591-599 J2 - Trans. ASABE OP - SN - 2151-0032 2151-0040 UR - http://dx.doi.org/10.13031/trans.59.11059 DB - Crossref ER - TY - JOUR TI - Structural Studies of Plant CESA Support Eighteen CESAs in the Plant CSC AU - Vandavasi, Venu G. AU - Putnam, Daniel K. AU - Zhang, Qiu AU - Petridis, Loukas AU - Heller, William T. AU - Nixon, B. Tracy AU - Haigler, Candace H. AU - Kalluri, Udaya AU - Coates, Leighton AU - Langan, Paul AU - Smith, Jeremy C. AU - Meiler, Jens AU - O'Neill, Hugh T2 - Biophysical Journal AB - The cellulose synthesis in plants is carried by a large multi-subunit transmembrane protein complex known as cellulose synthesis complex (CSC). The structural information on plant cellulose synthase (CESA) proteins that constitute CSC has remained challenging over years due to inherent complexities in the CSC leading to speculations and debates on the composition of CSC and the number of cellulose chains in a microfibril. Here, we report our findings on the structural properties of catalytic domain of Arabidopsis thaliana CESA1 (ATCESA1CatD) analyzed using small-angle scattering and computational modeling techniques. Our main findings include low resolution structures of ATCESA1CatD in monomeric and trimeric complex forms that provide the first experimental evidence supporting the self-assembly of CESAs into stable trimeric complexes. This is of immense importance in the context of CSC formation by plant CESAs and addresses a long standing question in plant biology - how many CESAs in the plant cellulose synthesis complex? Further, the scattering data in combination with computational modeling provided insight into the potential arrangement the monomers in the catalytic trimer and the relative arrangement of P-CR and CSR regions that are unique in the plants. Comparison of the size of the trimer complex with the dimensions of CSCs from TEM images provides compelling evidence that each lobe of a CSC contains three CESAs rather than the long-standing model of six CESAs within each lobe of a rosette CSC. To our knowledge, these studies are the first experimental evidence that CESA trimers form the lobes of rosette CSCs providing strong support for the hexamer of trimers model that synthesizes an 18-chain cellulose microfibril as the fundamental product of cellulose synthesis in plants. DA - 2016/2// PY - 2016/2// DO - 10.1016/J.BPJ.2015.11.208 VL - 110 IS - 3 SP - 27a J2 - Biophysical Journal LA - en OP - SN - 0006-3495 UR - http://dx.doi.org/10.1016/J.BPJ.2015.11.208 DB - Crossref ER - TY - JOUR TI - Nutrients in the nexus AU - Davidson, Eric A. AU - Nifong, Rachel L. AU - Ferguson, Richard B. AU - Palm, Cheryl AU - Osmond, Deanna L. AU - Baron, Jill S. T2 - Journal of Environmental Studies and Sciences AB - Synthetic nitrogen (N) fertilizer has enabled modern agriculture to greatly improve human nutrition during the twentieth century, but it has also created unintended human health and environmental pollution challenges for the twenty-first century. Averaged globally, about half of the fertilizer-N applied to farms is removed with the crops, while the other half remains in the soil or is lost from farmers’ fields, resulting in water and air pollution. As human population continues to grow and food security improves in the developing world, the dual development goals of producing more nutritious food with low pollution will require both technological and socio-economic innovations in agriculture. Two case studies presented here, one in sub-Saharan Africa and the other in Midwestern United States, demonstrate how management of nutrients, water, and energy is inextricably linked in both small-scale and large-scale food production, and that science-based solutions to improve the efficiency of nutrient use can optimize food production while minimizing pollution. To achieve the needed large increases in nutrient use efficiency, however, technological developments must be accompanied by policies that recognize the complex economic and social factors affecting farmer decision-making and national policy priorities. Farmers need access to affordable nutrient supplies and support information, and the costs of improving efficiencies and avoiding pollution may need to be shared by society through innovative policies. Success will require interdisciplinary partnerships across public and private sectors, including farmers, private sector crop advisors, commodity supply chains, government agencies, university research and extension, and consumers. DA - 2016/2/15/ PY - 2016/2/15/ DO - 10.1007/S13412-016-0364-Y VL - 6 IS - 1 SP - 25-38 J2 - J Environ Stud Sci LA - en OP - SN - 2190-6483 2190-6491 UR - http://dx.doi.org/10.1007/S13412-016-0364-Y DB - Crossref ER - TY - JOUR TI - Modifications to a LATE MERISTEM IDENTITY1 gene are responsible for the major leaf shapes of Upland cotton (Gossypium hirsutum L.) AU - Andres, Ryan J. AU - Coneva, Viktoriya AU - Frank, Margaret H. AU - Tuttle, John R. AU - Samayoa, Luis Fernando AU - Han, Sang-Won AU - Kaur, Baljinder AU - Zhu, Linglong AU - Fang, Hui AU - Bowman, Daryl T. AU - Rojas-Pierce, Marcela AU - Haigler, Candace H. AU - Jones, Don C. AU - Holland, James B. AU - Chitwood, Daniel H. AU - Kuraparthy, Vasu T2 - Proceedings of the National Academy of Sciences AB - Leaf shape varies spectacularly among plants. Leaves are the primary source of photoassimilate in crop plants, and understanding the genetic basis of variation in leaf morphology is critical to improving agricultural productivity. Leaf shape played a unique role in cotton improvement, as breeders have selected for entire and lobed leaf morphs resulting from a single locus, okra (l-D1), which is responsible for the major leaf shapes in cotton. The l-D1 locus is not only of agricultural importance in cotton, but through pioneering chimeric and morphometric studies, it has contributed to fundamental knowledge about leaf development. Here we show that an HD-Zip transcription factor homologous to the LATE MERISTEM IDENTITY1 (LMI1) gene of Arabidopsis is the causal gene underlying the l-D1 locus. The classical okra leaf shape allele has a 133-bp tandem duplication in the promoter, correlated with elevated expression, whereas an 8-bp deletion in the third exon of the presumed wild-type normal allele causes a frame-shifted and truncated coding sequence. Our results indicate that subokra is the ancestral leaf shape of tetraploid cotton that gave rise to the okra allele and that normal is a derived mutant allele that came to predominate and define the leaf shape of cultivated cotton. Virus-induced gene silencing (VIGS) of the LMI1-like gene in an okra variety was sufficient to induce normal leaf formation. The developmental changes in leaves conferred by this gene are associated with a photosynthetic transcriptomic signature, substantiating its use by breeders to produce a superior cotton ideotype. DA - 2016/12/20/ PY - 2016/12/20/ DO - 10.1073/PNAS.1613593114 VL - 114 IS - 1 SP - E57-E66 J2 - Proc Natl Acad Sci USA LA - en OP - SN - 0027-8424 1091-6490 UR - http://dx.doi.org/10.1073/PNAS.1613593114 DB - Crossref KW - cotton KW - leaf shape KW - okra KW - gene cloning ER - TY - JOUR TI - Efficacy of a Phosphate-Charged Soil Material in Supplying Phosphate for Plant Growth in Soilless Root Media AU - Oh, Y.-M. AU - Nelson, P.V. AU - Hesterberg, D.L. AU - Niedziela, C.E. T2 - International Journal of Agronomy AB - A soil material high in crystalline Fe hydrous oxides and noncrystalline Al hydrous oxides collected from the Bw horizon of a Hemcross soil containing allophane from the state of Oregon was charged with phosphate-P at rates of 0, 2.2, and 6.5 mg·g −1 , added to a soilless root medium at 5% and 10% by volume, and evaluated for its potential to supply phosphate at a low, stable concentration during 14 weeks of tomato ( Solanum esculentum L.) seedling growth. Incorporation of the soil material improved pH stability, whether it was charged with phosphate or not. Bulk solution phosphate-P concentrations in the range of 0.13 to 0.34 mg·dm −3 were associated with P deficiency. The only treatment that sustained an adequate bulk solution concentration of phosphate-P above 0.34 mg·dm −3 for the 14 weeks of testing contained 10% soil material charged with 6.5 mg·g −1 P, but initial dissolved P concentrations were too high (>5 mg·g −1 phosphate-P) from the standpoint of phosphate leaching. The treatment amended with 10% soil material charged with 2.2 mg·g −1 P maintained phosphate-P within an acceptable range of 0.4 to 2.3 mg·dm −3 for 48 d in a medium receiving no postplant phosphate fertilization. DA - 2016/// PY - 2016/// DO - 10.1155/2016/8296560 VL - 2016 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84965120040&partnerID=MN8TOARS ER - TY - JOUR TI - Desorption Characteristics of Three Mineral Oxides and a Non-crystalline Aluminosilicate for Supplying Phosphate in Soilless Root Media AU - Oh, Y.-M. AU - Hesterberg, D.L. AU - Nelson, P.V. AU - Niedziela, C.E. T2 - Communications in Soil Science and Plant Analysis AB - The objective was to evaluate phosphate desorption characteristics of synthetic hematite, goethite, and allophane and commercial alumina after loading at maximum adsorbed phosphate levels to determine their potential to release phosphate at a constant, low level to sustain plant growth in soilless media and reduce phosphate leaching. Desorption isotherms were measured at pH 6.4 ± 0.1 using a continuously stirred-flow reactor. The time period during which dissolved phosphate was maintained within the range of 5–0.2 mg·L−1 phosphate-P decreased in the order: allophane (12.4 d) > alumina (4.6 d) > goethite (3.6 d) > hematite (1.9 d). Allophane released the most phosphate during the desorption process (40% of maximum adsorbed phosphate; 12.7 mg∙g−1) followed by alumina and goethite (19–20%; ≈2.5 mg∙g−1) and lastly hematite (5%; 0.1 mg∙g−1). Allophane demonstrated the greatest potential as a phosphate-charged source for soilless root media, in amount and duration of phosphate release. DA - 2016/// PY - 2016/// DO - 10.1080/00103624.2016.1146753 VL - 47 IS - 6 SP - 753-760 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84964088588&partnerID=MN8TOARS KW - Allophane KW - alumina KW - aluminum oxide KW - goethite KW - hematite KW - iron oxide KW - phosphorous ER - TY - CONF TI - Development of a macro-pore flow and transport component for DRAINMOD, a step towards modeling phosphorus fate and transport in drained agricultural land AU - Askar, M.H. AU - Youssef, M.A. AU - Chescheir, G.M. AU - Hesterberg, D.L. AU - Amoozegar, A. AU - Skaggs, R.W. AB - Abstract. Artificially drained cropland has recently been identified as a possible source of elevated phosphourus (P) levels in Lake Erie. There is a growing need for developing new models or enhancing existing models to adequately represent different hydrological and biogeochemical processes affecting P fate and transport in artificially drained fields. Since P is highly immobile in soil, most P modeling studies have focused on surface runoff losses ignoring subsurface movement of P. Subsurface drainage, however, can be a critical pathway for P loss, particularly in the presence of macropore flow. Existing models lack or oversimplify integration of hydrological and biogeochemical processes regulating P dynamics in drained agro-ecosystems. A Phosphorus component to DRAINMOD suite of models, namely DRAINMOD-P, is currently being developed. Key hydrological and biochemical processes affecting P dynamics will be represented in the DRAINMOD-P model using a simple P cycle similar to the EPIC model. DRAINMOD hydrological component will be enhanced by adding routines for simulating macropore flow, a key pathway for subsurface transport of P, using procedures similar to MACRO model. The model will simulate water flow and solute transport in both soluble and particulate forms through macropores. The model will also be enhanced to simulate soil erosion and associated surface particulate P transport. The developed model will be tested using field measurements from artificially drained agricultural fields in North Carolina and Ohio. This abstract provides a detailed description of the modeling approach adopted in DRAINMOD to simulate the flow and transport in soil macro-pores C2 - 2016/// C3 - 10th International Drainage Symposium 2016 DA - 2016/// DO - 10.13031/ids.20162492913 VL - 2016-January SP - 151-155 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045761634&partnerID=MN8TOARS ER - TY - JOUR TI - Coal ash constituents at the base of aquatic food webs: Processes affecting bioaccumulation and trophic transfer AU - Lopez, A.R. AU - Hesterberg, D.R. AU - Funk, D.H. AU - Buchwalter, D.B. T2 - Water Resources Research Institute News of the University of North Carolina DA - 2016/// PY - 2016/// IS - 465 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85015255475&partnerID=MN8TOARS ER - TY - MGZN TI - 2016 sod producers’ report for North Carolina AU - Miller, G.L. T2 - North Carolina Turfgrass DA - 2016/// PY - 2016/// SP - 10–13 M1 - July/Aug ER - TY - MGZN TI - School’s out, what now? AU - Miller, G.L. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 SP - 50 M1 - 7 ER - TY - MGZN TI - License to kill AU - Miller, G.L. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 SP - 50 M1 - 5 ER - TY - MGZN TI - Wet, wet, wet AU - Miller, G.L. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 SP - 50 M1 - 3 ER - TY - RPRT TI - 2016 top performing tall fescue and Kentucky bluegrass cultivars for North Carolina AU - Miller, G.L. DA - 2016/9/2/ PY - 2016/9/2/ ER - TY - MGZN TI - Politics, Politics, Politics AU - Miller, G.L. T2 - SportsTurf DA - 2016/// PY - 2016/// VL - 32 SP - 50 M1 - 11 ER - TY - CONF TI - Evaluation of key methodology for digital image analysis of turfgrass color AU - Zhang, C. AU - Pinnix, G.D. AU - Zhang, Z. AU - Miller, G.L. AU - Rufty, T.W. T2 - 5th ETS Conference C2 - 2016/// C3 - Journal of European Turfgrass, Proceedings of the 5th ETS Conference CY - Algarve, Portugal DA - 2016/// PY - 2016/6/5/ SP - 65-66 ER - TY - CONF TI - Using turf colorants and pigments for potential long-term color of dormant warm-season grasses AU - Miller, G.L. AU - McCarty, L.B. C2 - 2016/// C3 - Journal European Turfgrass, Proceedings of 5th ETS Conference CY - Algarve, Portugal DA - 2016/// PY - 2016/6/5/ SP - 59-60 ER - TY - SOUND TI - Managing People and Pests on K-12 Fields AU - Miller, Grady DA - 2016/11/15/ PY - 2016/11/15/ ER - TY - SOUND TI - Comparison of color parameters of green turf colorants applied to bermudagrass AU - Miller, Grady DA - 2016/11/8/ PY - 2016/11/8/ ER - TY - SOUND TI - NC’s Role in Developing Drought Tolerant Warm-Season Turfgrasses for the Southeast AU - Miller, Grady DA - 2016/11/7/ PY - 2016/11/7/ ER - TY - SOUND TI - Turfgrass Response to Athletic Field Paint AU - Miller, Grady DA - 2016/1/20/ PY - 2016/1/20/ ER - TY - RPRT TI - 2016 Spring green-up of warm-season grasses AU - Miller, G.L. A3 - Turffiles (Turfgrass Information for North Carolina) DA - 2016/4/19/ PY - 2016/4/19/ SP - 1 PB - Turffiles (Turfgrass Information for North Carolina) ER - TY - CONF TI - Identification of zoysiagrass genotypes with resistance to large patch under controlled environmental conditions AU - Zuleta, M.C. AU - Gomez, S.P. AU - Arellano, C. AU - Flor, N. AU - Harmon, P.F. AU - Kenworthy, K.E. AU - Milla-Lewis, S.R. C2 - 2016/6/5/ C3 - Journal of European Turfgrass Society, Proceedings of 5th ETS Conference DA - 2016/6/5/ SP - 157–158 ER - TY - CONF TI - Release of KSUZ0802 zoysiagrass AU - Chandra, A. AU - Fry, J.D. AU - Genovesi, A.D. AU - Meeks, M. AU - Engelke, M.C. AU - Zhang, Q. AU - Okeyo, D. AU - Moss, J.Q. AU - Ervin, E.H. AU - Xiong, X. AU - Milla-Lewis, S.R. AU - Brosnan, J.T. AU - Griffin, J. AU - Parsons, L. C2 - 2016/11/6/ C3 - Proc. Amer. Soc. Agron. Intl. Ann. Mtg. DA - 2016/11/6/ ER - TY - SOUND TI - Quantitative trait loci (QTL) mapping of winter survival in zoysiagrass AU - Pruitt, M.H. AU - Dunne, J.C. AU - Schwartz, B.M. AU - Patton, A.J. AU - C., Arellano AU - Milla-Lewis, S.R. DA - 2016/8/15/ PY - 2016/8/15/ ER - TY - CONF TI - Quantitative trait loci (QTL) analysis of freezing tolerance in zoysiagrass AU - Pruitt, M.H. AU - Milla-Lewis, S.R. AU - Schwartz, B.M. AU - Patton, A.J. AU - C, Arellano C2 - 2016/11/6/ C3 - Proc. Amer. Soc. Agron. Intl. Ann. Mtg. DA - 2016/11/6/ ER - TY - CONF TI - Proteomics of cold acclimation in zoysiagrass AU - Pruitt, M.H. AU - Milla-Lewis, S.R. AU - Livingston, D.P. AU - Tuong, T.D. AU - Arellano, C. C2 - 2016/11/6/ C3 - Proc. Amer. Soc. Agron. Intl. Ann. Mtg. DA - 2016/11/6/ ER - TY - CONF TI - Optimization of SNP identification by genotype by sequencing (GBS) in polyploid zoysiagrass AU - Yu, X. AU - Dunne, J.C. AU - Pruitt, M.H. AU - Milla-Lewis, S.R. C2 - 2016/11/6/ C3 - Proc. Amer. Soc. Agron. Intl. Ann. Mtg DA - 2016/11/6/ ER - TY - CONF TI - Varying management practices for the improvement of bermudagrass accessions under low light conditions AU - Dunne, J.C. AU - Reynolds, W.C. AU - Arellano, C. AU - Miller, G.L. AU - Milla-Lewis, S.R. C2 - 2016/6/5/ C3 - Proceedings of 5th ETS Conference DA - 2016/6/5/ SP - 27–28 PB - Journal of European Turfgrass Society ER - TY - CONF TI - Use of genotype by sequencing to develop a high density SNP-based linkage map in zoysiagrass AU - Milla-Lewis, S.R. AU - Pruitt, H.M. AU - Dunne, J.C. AU - Zuleta, M.C. AU - Schwartz, B.M. AU - Patton, A.J. AU - Arellano, C. C2 - 2016/6/5/ C3 - Proceedings of 5th ETS Conference DA - 2016/6/5/ SP - 19-20 PB - Journal of European Turfgrass Society ER - TY - SOUND TI - Development and application of genomic tools for warm-season grasses AU - Milla-Lewis, S.R. DA - 2016/12/14/ PY - 2016/12/14/ M3 - invited presentation ER - TY - SOUND TI - Breeding turfgrasses for stress tolerance and pest resistance in the transition zone AU - Milla-Lewis, S.R. DA - 2016/1/13/ PY - 2016/1/13/ M3 - invited presentation ER - TY - SOUND TI - Breeding improved turfgrasses for North Carolina and the transition zone AU - Milla-Lewis, S.R. DA - 2016/1/13/ PY - 2016/1/13/ M3 - invited presentation ER - TY - SOUND TI - Greenhouse evaluation of Miscanthus and Arundo accessions for nutrient uptake ability AU - Moore, K.A. AU - Gannon, T.G. AU - Castillo, M.S. AU - Ranney, T.G. AU - Touchell, D.H. AU - Milla-Lewis, S.R. DA - 2016/8/15/ PY - 2016/8/15/ ER - TY - SOUND TI - Field and laboratory evaluation of African bermudagrass germplasm for freezing tolerance AU - Dunne, J.C. AU - Tuong, T.D. AU - Livingston, D.P. AU - Milla-Lewis, S.R. DA - 2016/11/6/ PY - 2016/11/6/ ER - TY - JOUR TI - Rapid wood decay and nutrient mineralization in an old-growth bottomland hardwood forest AU - Ricker, Matthew C. AU - Lockaby, B. Graeme AU - Blosser, Gavin D. AU - Conner, William H. T2 - Biogeochemistry DA - 2016/1/23/ PY - 2016/1/23/ DO - 10.1007/s10533-016-0183-y VL - 127 IS - 2-3 SP - 323-338 J2 - Biogeochemistry LA - en OP - SN - 0168-2563 1573-515X UR - http://dx.doi.org/10.1007/s10533-016-0183-y DB - Crossref KW - Wood decomposition KW - Old-growth forest KW - Floodplain biogeochemistry ER - TY - JOUR TI - Effects of forested floodplain soil properties on phosphorous concentrations in two Chesapeake Bay sub-watersheds, Virginia, USA AU - Odhiambo, B. K. AU - Ricker, M. C. AU - Le Blanc, L. M. AU - Moxey, K. A. T2 - Environmental Science and Pollution Research DA - 2016/5/5/ PY - 2016/5/5/ DO - 10.1007/s11356-016-6668-3 VL - 23 IS - 16 SP - 16056-16066 J2 - Environ Sci Pollut Res LA - en OP - SN - 0944-1344 1614-7499 UR - http://dx.doi.org/10.1007/s11356-016-6668-3 DB - Crossref KW - Stream phosphorus KW - Riparian soils KW - Legacy sediment KW - Water quality ER - TY - JOUR TI - Climatic, ecological, and socioeconomic factors associated with West Nile virus incidence in Atlanta, Georgia, U.S.A. AU - Lockaby, Graeme AU - Noori, Navideh AU - Morse, Wayde AU - Zipperer, Wayne AU - Kalin, Latif AU - Governo, Robin AU - Sawant, Rajesh AU - Ricker, Matthew T2 - Journal of Vector Ecology AB - The integrated effects of the many risk factors associated with West Nile virus (WNV) incidence are complex and not well understood. We studied an array of risk factors in and around Atlanta, GA, that have been shown to be linked with WNV in other locations. This array was comprehensive and included climate and meteorological metrics, vegetation characteristics, land use / land cover analyses, and socioeconomic factors. Data on mosquito abundance and WNV mosquito infection rates were obtained for 58 sites and covered 2009–2011, a period following the combined storm water – sewer overflow remediation in that city. Risk factors were compared to mosquito abundance and the WNV vector index (VI) using regression analyses individually and in combination. Lagged climate variables, including soil moisture and temperature, were significantly correlated (positively) with vector index as were forest patch size and percent pine composition of patches (both negatively). Socioeconomic factors that were most highly correlated (positively) with the VI included the proportion of low income households and homes built before 1960 and housing density. The model selected through stepwise regression that related risk factors to the VI included (in the order of decreasing influence) proportion of houses built before 1960, percent of pine in patches, and proportion of low income households. DA - 2016/11/17/ PY - 2016/11/17/ DO - 10.1111/jvec.12218 VL - 41 IS - 2 SP - 232-243 J2 - Journal of Vector Ecology LA - en OP - SN - 1081-1710 UR - http://dx.doi.org/10.1111/jvec.12218 DB - Crossref KW - West Nile virus KW - water quality KW - socioeconomic health risk KW - forest cover loss KW - urbanization KW - climate induced health risk ER - TY - JOUR TI - Diversity and Spatial Heterogeneity of Weed Communities in a Sugarcane Cropping System in the Dry Tropics of Costa Rica AU - Leon, Ramon G. AU - Agüero, Renán AU - Calderón, Diego T2 - Weed Science AB - Weed diversity, structure, and distribution within and outside agricultural fields affect not only ecological processes but also weed management strategies. We studied how areas managed differently within and outside the field determine weed communities in a sugarcane cropping system in the dry tropics of Costa Rica. A total of 120 weed species were detected, which was similar to surveys conducted in subtropical and temperate conditions. Weed species richness was highest in undisturbed field borders and lowest in rows and furrows. The area where tractors turn within the field (turn area) had similar richness compared with the borders, despite being one of the most disturbed management areas studied. The most predominant weed species were divided between generalists and species that exhibited clear preferences for management area or soil texture. Soil texture was more important for determining weed community structure than management area when considering weed species affecting weed control decisions. The results indicated that disturbance in the management area and, especially, weed control practices are critical factors affecting weed diversity, but availability of resources for weed growth such as nutrients, soil moisture, and light can mitigate some of the limitations imposed by weed control on weed diversity, especially in the turn area. Differences in weed communities between management areas within fields indicated the existence of conditions that favor key weed species, and this information can be used to anticipate their population growth and help determine when and where more intensive control should be implemented. DA - 2016/11// PY - 2016/11// DO - 10.1614/ws-d-16-00066.1 VL - 65 IS - 01 SP - 128-140 KW - control KW - disturbance KW - diversity KW - habitat KW - soil KW - texture KW - tropicsweed ER - TY - SOUND TI - Cover crop mixture proportion and starter fertilizer effects on weed competition and grain yield in organic rotational no-till maize production AU - Atwell, R.A. AU - Mirsky, S.B. AU - Poffenbarger, H.J. AU - Reberg-Horton, S.C. DA - 2016/// PY - 2016/// ER - TY - SOUND TI - Utilizing cover crop mulches for weed control in conventional and organic cotton production AU - Atwell, R.A. AU - Reberg-Horton, S.C. AU - Edmisten, K.L. AU - York, A.C. DA - 2016/// PY - 2016/// M3 - poster ER - TY - SOUND TI - Organic Grain Production in the Southern United States: How a System of Do Nots Creates Sustainability AU - Reberg-Horton, S.C. DA - 2016/// PY - 2016/// ER - TY - NEWS TI - Identifying regionally adapted winter pea varieties for use as grain, forage, and cover crops T2 - NC Organic Grains Newsletter PY - 2016/// ER - TY - SOUND TI - Identifying regionally adapted winter pea genotypes that maximize grain, forage, and cover crop potential in the Southeast USA AU - Atwell, R.A. AU - Reberg-Horton, S.C. AU - Mirsky, S.B. AU - Castillo, M.S. AU - McGee, R.J. DA - 2016/// PY - 2016/// ER - TY - SOUND TI - Starter fertilizer and application method effects on weed competition and grain yield when using a cover crop mulch in organic corn production AU - Atwell, R.A. AU - Reberg-Horton, S.C. AU - Mirsky, S.B. AU - Poffenbarger, H.J. AU - Zinati, G.M. AU - Moyer, J.W. DA - 2016/// PY - 2016/// M3 - poster ER - TY - JOUR TI - Row spacing and seeding rate effects on canola population, weed competition, and yield in winter organic canola production AU - Atwell, R.A. AU - Reberg-Horton, S.C. T2 - Agronomy Journal DA - 2016/// PY - 2016/// VL - 108 SP - 2425–2432 ER - TY - JOUR TI - Weed control in Florida pastures using aminocyclopyrachlor AU - Abe, D.G. AU - Sellers, B.A. AU - Ferrell, J.A. AU - Leon, R.G. AU - Odero, D.C. T2 - Weed Technology AB - Studies under Florida conditions for susceptibility of pasture weed species to the new herbicide, aminocyclopyrachlor (ACP), are essential. Sensitivity of weed species was dependent upon the species and environment. Whitehead broom was not susceptible to ACP. Dogfennel control was consistently above 85% 1 yr after treatment with ACP at 140 g ha −1 and all ACP premixes. Milkpea was initially sensitive to all ACP treatments, but regrowth was evident in all treatments after 1 yr at one location. All ACP treatments resulted in 100% control of tropical soda apple 1 yr after treatment at one location, but less than 50% control at a second location. Herbicide applications with ACP, when labeled, will likely provide good to excellent control (80 to 100%) of several weed species. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00052.1 VL - 30 IS - 01 SP - 271–278 KW - Pasture KW - postemergence KW - premix KW - weed control ER - TY - JOUR TI - Tolerance of bermudagrass and stargrass toaminocyclopyrachlor AU - Abe, D.G. AU - Sellers, B.A. AU - Ferrell, J.A. AU - Leon, R.G. AU - Odero, D.C. T2 - Weed Technology AB - The tolerance of bermudagrass and stargrass to the relatively new herbicide, aminocyclopyrachlor (ACP), must be known before it can be recommended for weed control in these forage systems. Field experiments were conducted in 2012 and 2013 in south-central Florida to determine the tolerance of established bermudagrass and stargrass to various rates and combinations of ACP, chlorsulfuron, 2,4-D, triclopyr, and metsulfuron. Overall, bermudagrass and stargrass injury was transient and was minimal by 60 d after treatment (DAT). Similarly, biomass production was negatively affected at 30 DAT when treated with ACP at rates of 70 g ae ha −1 or greater, but was similar to the nontreated control by 60 DAT. Tank-mixing ACP with chlorsulfuron, 2,4-D amine, triclopyr, or metsulfuron did not increase injury compared with ACP alone applied at equivalent rates. Forage nutritive values were unaffected by herbicides. These data suggest that long-term effects of ACP on bermudagrass and stargrass are negligible, and this herbicide could be an important component of weed management programs in these forage systems. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00167.1 VL - 30 IS - 02 SP - 499–505 KW - Forages KW - hayfields KW - pastures ER - TY - JOUR TI - Technology for automation weed control in specialty crops AU - Fennimore, S.A. AU - Slaughter, D.C. AU - Siemens, M.C. AU - Leon, R.G. AU - Saber, M.N. T2 - Weed Technology AB - Specialty crops, like flowers, herbs, and vegetables, generally do not have an adequate spectrum of herbicide chemistries to control weeds and have been dependent on hand weeding to achieve commercially acceptable weed control. However, labor shortages have led to higher costs for hand weeding. There is a need to develop labor-saving technologies for weed control in specialty crops if production costs are to be contained. Machine vision technology, together with data processors, have been developed to enable commercial machines to recognize crop row patterns and control automated devices that perform tasks such as removal of intrarow weeds, as well as to thin crops to desired stands. The commercial machine vision systems depend upon a size difference between the crops and weeds and/or the regular crop row pattern to enable the system to recognize crop plants and control surrounding weeds. However, where weeds are large or the weed population is very dense, then current machine vision systems cannot effectively differentiate weeds from crops. Commercially available automated weeders and thinners today depend upon cultivators or directed sprayers to control weeds. Weed control actuators on future models may use abrasion with sand blown in an air stream or heating with flaming devices to kill weeds. Future weed control strategies will likely require adaptation of the crops to automated weed removal equipment. One example would be changes in crop row patterns and spacing to facilitate cultivation in two directions. Chemical company consolidation continues to reduce the number of companies searching for new herbicides; increasing costs to develop new herbicides and price competition from existing products suggest that the downward trend in new herbicide development will continue. In contrast, automated weed removal equipment continues to improve and become more effective. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-16-00070.1 VL - 30 IS - 04 SP - 823–37 ER - TY - JOUR TI - Seed production and control of sicklepod (Senna obtusifolia) and pitted morningglory (Ipomoea lacunosa) with 2,4-D, dicamba, and glyphosate combinations AU - Leon, R.G. AU - Ferrell, J.A. AU - Sellers, B.A. T2 - Weed Technology AB - Sicklepod and pitted morningglory are two of the most important weed species in row-crop production in the southeastern United States. The upcoming introduction of soybean and cotton varieties resistant to 2,4-D and dicamba will increase the reliance on these auxinic herbicides. However, it is not clear how these herbicides will affect sicklepod and pitted morningglory control. Field experiments were conducted in 2013 and 2014 in Jay, FL to determine whether 2,4-D (560 and 1,120 g ae ha −1 ), dicamba (420 and 840 g ae ha −1 ), and glyphosate (1,060 g ae ha −1 ) alone or in combination applied when weed shoots were 11 (early POST [EPOST]) and 22 (late POST [LPOST]) cm long effectively control and prevent seed production of sicklepod and pitted morningglory. LPOST provided more effective control of sicklepod than EPOST. This was attributed to emergence of sicklepod seedlings after the EPOST application. When glyphosate was tank mixed with 2,4-D or dicamba, sicklepod control was higher (78 to 89% and 87 to 98% in 2013 and 2014, respectively) than for single-herbicide treatments (45 to 77% and 38 to 80% in 2013 and 2014, respectively) 6 wk after treatment (WAT). Pitted morningglory control was not affected by application timing, and 2,4-D provided 91 to 100% 6 WAT, which was equivalent to treatments with tank mixtures containing glyphosate. Dicamba applied at 420 g ha −1 had the lowest pitted morningglory control (44 to 70% and 82 to 86% in 2013 and 2014, respectively). Sicklepod and pitted morningglory plants that survived and recovered from herbicide treatments produced the same number of viable seeds as nontreated plants in most treatments. The results of the present study indicated that the use of 2,4-D and dicamba alone will not provide adequate extended control of sicklepod, and the use of tank mixtures that combine auxinic herbicides with glyphosate or other POST herbicides will be necessary to manage sicklepod adequately in 2,4-D- or dicamba-resistant soybean and cotton. Because sicklepod plants that survived a single herbicide application are capable of producing abundant viable seeds, integrated approaches that include PRE herbicides and sequential POST control options may be necessary to ensure weed seed bank reductions. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00108.1 VL - 30 IS - 01 SP - 76–84 KW - Integrated weed management KW - seed bank KW - tank mixtures ER - TY - JOUR TI - Relative lateral movement in surface soil of amicarbazone and indaziflam compared to other preemergence herbicide for turfgrass AU - Leon, R.G. AU - Unruh, J.B. AU - Brecke, B.J. T2 - Weed Technology AB - Amicarbazone and indaziflam are relatively new herbicides that provide effective control of important weed species in turfgrass. A concern for golf course superintendents and turfgrass managers is the lack of information about runoff risk of these two herbicides, which is a limitation to their proper and safe use. The objectives of this research were (1) to compare lateral movement in surface soil of amicarbazone and indaziflam to other commonly used PRE herbicides in turfgrass (i.e., dithiopyr, prodiamine, pronamide, simazine) and (2) to determine whether incorporating the herbicide with irrigation before a simulated storm event reduces lateral movement. Herbicides were applied at full label rates in two locations (Jay and Milton, FL) with 14% slope, and lateral movement was evaluated using perennial ryegrass and annual bluegrass as bioindicators. Incorporating PRE herbicides with irrigation a few hours before a major simulated storm event did not reduce lateral movement of any of the herbicides evaluated. All herbicides moved outside the treated area regardless of the presence of a simulated storm event. Herbicide lateral movement varied from 61 to 153 cm in Jay, and from 5 to 103 cm in Milton. The Milton location had higher sand content and lower organic matter content than Jay, which favored water infiltration. No herbicide effects were observed 210 cm downslope from the treated area. On the basis of our results, the ranking from highest to lowest lateral movement was pronamide > simazine ≥ indaziflam > amicarbazone ≥ dithiopyr > prodiamine. The difference in lateral movement was approximately 60 to 80 cm between pronamide and prodiamine depending on location and evaluation timing for the 14% slope at the study sites. The results of the present study provide guidance for golf course superintendents and turfgrass managers to determine buffer zones in sensitive areas. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00126.1 VL - 30 IS - 01 SP - 229–237 KW - Integrated weed management KW - environmental impact KW - safety KW - water quality KW - herbicide movement KW - landscape ER - TY - JOUR TI - Peanut cultivars differing in growth habit and canopy architecture respond similarly to weed interference AU - Leon, R.G. AU - Mulvaney, M.J. AU - Tillman, B.L. T2 - Peanut Science AB - ABSTRACT It has been proposed that crops can be improved to be more competitive with weeds by increasing their ability to suppress weed growth and reproduction. Weed suppressive ability is predominantly influenced by plant architectures that favor shading and rapid canopy closure. A three-yr field experiment was conducted in Jay, FL to assess the response of peanut cultivars with different growth habits to weed interference. Three cultivars (‘Bailey', erect growth and tall canopy height; ‘Georgia-06G', semi-bunch and intermediate height; ‘TUFRunner 727’, prostrate growth and intermediate height) and one advanced breeding line (‘UFT312’, very prostrate growth and short canopy height) were subjected to three weed interference levels: no interference, early season interference, and full-season interference. Results showed that, despite differences in growth habit, morphological response to weed interference was similar among peanut cultivars. All cultivars suppressed weed growth more than 76% in 2 of 3 yr. Peanut reduced reproductive growth and maintained vegetative growth under weed interference scenarios, and yields decreased as interference duration increased. Competitiveness of peanut to weeds could be improved by identification of lines that better balance translocation of photoassimilates favoring kernels over vegetative growth. DA - 2016/// PY - 2016/// DO - 10.3146/ps16-3.1 VL - 43 IS - 2 SP - 133–140 ER - TY - JOUR TI - Influence of planting depth and application timing on S-metolachlor injury in sesame (Sesamum indicum L.) AU - Sperry, B.P. AU - Ferrell, J.A. AU - Leon, R.G. AU - Rowland, D.L. AU - Mulvaney, M.J. T2 - Weed Technology AB - Two experiments were conducted in 2015 at multiple locations in Florida to evaluate the effects of planting depth and application timing on S -metolachlor injury in sesame. In both studies, sesame responded negatively to increases in S -metolachlor rate. Altering sesame planting depth did not provide increased safety to PRE S -metolachlor applications. Sesame establishment declined with increased planting depth, likely because of the physical inability of the small seed to emerge from the 3.8-cm depth. Delaying applications of S -metolachlor by 3 or 6 d after planting (DAP) consistently improved sesame establishment. Applications 3 and 6 DAP resulted in 89 to 92% seedling emergence at 2 wk after planting (WAP), relative to 55 to 63% emergence when S -metolachlor was applied the day of planting (0 DAP) or 3 days before (−3 DAP), respectively. Applications 3 DAP resulted in 21 and 2% plant stunting when evaluated 3 and 6 WAP, respectively, whereas all other timings caused 25 to 51% stunting. Yield was reduced 22 and 33% by the −3 DAP and 0 DAP application timings, respectively, whereas no reduction in yield was observed by the delayed application timings. Therefore, delaying applications of S -metolachlor by 3 to 6 days will likely result in improved sesame seedling establishment and total seed yield. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-16-00081.1 VL - 30 IS - 04 SP - 958–964 KW - Application timing KW - crop injury KW - planting depth ER - TY - JOUR TI - Bahiagrass tolerance to aminocyclopyrachlor in Florida AU - Abe, D.G. AU - Sellers, B.A. AU - Ferrell, J.A. AU - Leon, R.G. AU - Odero, D.C. T2 - Weed Technology AB - Two varieties of bahiagrass were evaluated under Florida conditions for forage tolerance to the new herbicide, aminocyclopyrachlor (ACP), which is essential for product development decisions. Herbicide treatments included ACP alone at 70 and 140 g ai ha −1 , ACP + chlorsulfuron at 69 + 27 and 138 + 54 g ai ha −1 , ACP + 2,4-D amine at 70 + 532 g ai ha −1 and 140 + 1,064 g ai ha −1 , ACP + triclopyr-amine at 70 + 140 g ai ha −1 and 140 + 280 g ai ha −1 , and ACP + metsulfuron at 46 + 7, 78 + 12, and 168 + 26 g ai ha −1 , and also included a nontreated check. ‘Argentine’ bahiagrass was the most tolerant forage species, and ‘Pensacola’ bahiagrass was sensitive to ACP + metsulfuron and initially to ACP + chlorsulfuron. Herbicide applications using ACP, when labeled, will likely provide good to excellent control of several weed species, with little long-term impact on bahiagrass forage production when the cultivar is known. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-16-00060.1 VL - 30 IS - 04 SP - 943–948 KW - 'Argentine' bahiagrass KW - 'Pensacola' bahiagrass KW - pasture KW - warm-season forage ER - TY - JOUR TI - Digital image quantification of siderophores on agar plates AU - Andrews, M.Y. AU - Santelli, C.M. AU - Duckworth, O.W. T2 - Data in Brief AB - This article presents visual image data and detailed methodology for the use of a new method for quantifying the exudation of siderophores during fungal growth. The data include images showing time series for calibration, fungal exudation, and negative controls, as well as replication accuracy information. In addition, we provide detailed protocols for making CAS assay layer plates, the digital analysis protocol for determining area of color change, and discuss growth media that do and do not work with the layer plate method. The results of these data, their interpretation, and further discussion can be found in Andrews et al., 2016 [1]. DA - 2016/// PY - 2016/// DO - 10.1016/j.dib.2016.01.054 VL - 6 SP - 890-898 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84957059723&partnerID=MN8TOARS ER - TY - JOUR TI - Morphology, Structure, and Metal Binding Mechanisms of Biogenic Manganese Oxides in a Superfund Site Treatment System AU - Duckworth, O.W. AU - Rivera, N.A. AU - Gardner, T.G. AU - Andrews, M.Y. AU - Santelli, C.M. AU - Polizzotto, M.L. T2 - Duckworth, O. W., Rivera, N.A., Gardner, T.G., Andrews, M.Y., Santelli, C.M., and Polizzotto, M.L. 2016. Morphology, Structure, and Metal Binding Mechanisms of Biogenic Manganese Oxides in a Superfund Site Treatment System. Environmental Science: Process & Impacts 19:50-58 DA - 2016/// PY - 2016/// VL - 19 SP - 50–58 ER - TY - CHAP TI - Biogeochemical Processes Underpin Ecosystem Services AU - Duckworth, O.W. AU - Franzluebbers, A.J. AU - Gardner, T.G. T2 - Soil Ecosystems Services A2 - Stromberger, M. A2 - Comerford, N. A2 - Lindbo, D. PY - 2016/// DO - 10.2136/2015.soilecosystemsservices.2015.0024. ER - TY - JOUR TI - Symbiotic Nitrogen Fixation and the Challenges to Its Extension to Nonlegumes AU - Mus, Florence AU - Crook, Matthew B. AU - Garcia, Kevin AU - Costas, Amaya Garcia AU - Geddes, Barney A. AU - Kouri, Evangelia D. AU - Paramasivan, Ponraj AU - Ryu, Min-Hyung AU - Oldroyd, Giles E. D. AU - Poole, Philip S. AU - Udvardi, Michael K. AU - Voigt, Christopher A. AU - Ané, Jean-Michel AU - Peters, John W. T2 - Applied and Environmental Microbiology AB - Access to fixed or available forms of nitrogen limits the productivity of crop plants and thus food production. Nitrogenous fertilizer production currently represents a significant expense for the efficient growth of various crops in the developed world. There are significant potential gains to be had from reducing dependence on nitrogenous fertilizers in agriculture in the developed world and in developing countries, and there is significant interest in research on biological nitrogen fixation and prospects for increasing its importance in an agricultural setting. Biological nitrogen fixation is the conversion of atmospheric N2 to NH3, a form that can be used by plants. However, the process is restricted to bacteria and archaea and does not occur in eukaryotes. Symbiotic nitrogen fixation is part of a mutualistic relationship in which plants provide a niche and fixed carbon to bacteria in exchange for fixed nitrogen. This process is restricted mainly to legumes in agricultural systems, and there is considerable interest in exploring whether similar symbioses can be developed in nonlegumes, which produce the bulk of human food. We are at a juncture at which the fundamental understanding of biological nitrogen fixation has matured to a level that we can think about engineering symbiotic relationships using synthetic biology approaches. This minireview highlights the fundamental advances in our understanding of biological nitrogen fixation in the context of a blueprint for expanding symbiotic nitrogen fixation to a greater diversity of crop plants through synthetic biology. DA - 2016/4// PY - 2016/4// DO - 10.1128/aem.01055-16 VL - 82 IS - 13 SP - 3698-3710 ER - TY - JOUR TI - The transportome of mycorrhizal systems AU - Courty, Pierre-Emmanuel AU - Doidy, Joan AU - Garcia, Kevin AU - Wipf, Daniel AU - Zimmermann, Sabine Dagmar T2 - Molecular Mycorrhizal Symbiosis AB - Mycorrhizal colonization of plant roots increases the sink strength and creates an additional sugar demand for the plant. Nutrient uptake from soil and exchanges between fungal and plant partners forming mycorrhizal symbioses present a mean feature among the beneficial effects of these mutualistic relationships. In the mycorrhizal associations, in return for mineral nutrient provisioning, the plant provides sugar photosynthates to the heterotrophic symbiont. This trade is regulated by both plant and fungal transport components, as for instance the long-distance transport of sucrose from leaves towards mycorrhizal roots and subsequent cellular transfer of monosaccharides at the symbiotic interface. This chapter provides recent knowledge concerning mycorrhizal nutrient exchanges and the involved molecular players in membrane transport of the ecto- and endomycorrhizal partners. It summarizes transport of sugars from plants towards mycorrhizal fungi. The chapter reviews uptake and exchange of main nutrients such as nitrogen, phosphate, sulfate, potassium, and water by the symbiotic partners. DA - 2016/10// PY - 2016/10// DO - 10.1002/9781118951446.ch14 SP - 239-256 ER - TY - JOUR TI - Take a Trip Through the Plant and Fungal Transportome of Mycorrhiza AU - Garcia, Kevin AU - Doidy, Joan AU - Zimmermann, Sabine D. AU - Wipf, Daniel AU - Courty, Pierre-Emmanuel T2 - Trends in Plant Science AB - Soil nutrient acquisition and exchanges through symbiotic plant-fungus interactions in the rhizosphere are key features for the current agricultural and environmental challenges. Improved crop yield and plant mineral nutrition through a fungal symbiont has been widely described. In return, the host plant supplies carbon substrates to its fungal partner. We review here recent progress on molecular players of membrane transport involved in nutritional exchanges between mycorrhizal plants and fungi. We cover the transportome, from the transport proteins involved in sugar fluxes from plants towards fungi, to the uptake from the soil and exchange of nitrogen, phosphate, potassium, sulfate, and water. Together, these advances in the comprehension of the mycorrhizal transportome will help in developing the future engineering of new agro-ecological systems. DA - 2016/11// PY - 2016/11// DO - 10.1016/j.tplants.2016.07.010 VL - 21 IS - 11 SP - 937-950 ER - TY - JOUR TI - Comparative Analysis of Secretomes from Ectomycorrhizal Fungi with an Emphasis on Small-Secreted Proteins AU - Garcia, Kevin AU - Ané, Jean-Michel T2 - Frontiers in Microbiology AB - FRONTIERS COMMENTARY article Front. Microbiol., 02 November 2016 Volume 7 - 2016 | https://doi.org/10.3389/fmicb.2016.01734 DA - 2016/11/2/ PY - 2016/11/2/ DO - 10.3389/fmicb.2016.01734 VL - 7 KW - ectomycorrhizal KW - saprotrophs KW - secretomics KW - small-secretedproteins KW - symbiosis KW - secretomes ER - TY - JOUR TI - A proteomic atlas of the legume Medicago truncatula and its nitrogen-fixing endosymbiont Sinorhizobium meliloti AU - Marx, Harald AU - Minogue, Catherine E AU - Jayaraman, Dhileepkumar AU - Richards, Alicia L AU - Kwiecien, Nicholas W AU - Siahpirani, Alireza F AU - Rajasekar, Shanmugam AU - Maeda, Junko AU - Garcia, Kevin AU - Valle-Echevarria, Angel R Del AU - Volkening, Jeremy D AU - Westphall, Michael S AU - Roy, Sushmita AU - Sussman, Michael R AU - Ané, Jean-Michel AU - Coon, Joshua J T2 - Nature Biotechnology AB - Legumes are essential components of agricultural systems because they enrich the soil in nitrogen and require little environmentally deleterious fertilizers. A complex symbiotic association between legumes and nitrogen-fixing soil bacteria called rhizobia culminates in the development of root nodules, where rhizobia fix atmospheric nitrogen and transfer it to their plant host. Here we describe a quantitative proteomic atlas of the model legume Medicago truncatula and its rhizobial symbiont Sinorhizobium meliloti, which includes more than 23,000 proteins, 20,000 phosphorylation sites, and 700 lysine acetylation sites. Our analysis provides insight into mechanisms regulating symbiosis. We identify a calmodulin-binding protein as a key regulator in the host and assign putative roles and targets to host factors (bioactive peptides) that control gene expression in the symbiont. Further mining of this proteomic resource may enable engineering of crops and their microbial partners to increase agricultural productivity and sustainability. DA - 2016/10// PY - 2016/10// DO - 10.1038/nbt.3681 VL - 34 IS - 11 SP - 1198-1205 ER - TY - JOUR TI - Using Land-Use Change, Soil Characteristics, and a Semi-Automated On-Line GIS Database to Inventory Carolina Bays AU - Sullivan, Dana G. AU - White, Jeffrey G. AU - Vepraskas, Michael J. T2 - Wetlands DA - 2016/11/2/ PY - 2016/11/2/ DO - 10.1007/s13157-016-0842-8 VL - 37 IS - 1 SP - 89-98 KW - Carolina Bay KW - Wetland KW - Land-use change KW - Remote sensing KW - Inventory KW - Geographic information system (GIS) KW - Landsat KW - Image analysis and classification ER - TY - CHAP TI - Estimating Statewide Soil Moisture Using an In Situ Sensing Network and Passive Microwave Remote Sensing AU - White, J.G. AU - D’Aiuto, C. AU - Heitman, J. T2 - STEM and GIS in Higher Education A2 - Cowen, David PY - 2016/// SP - 15 PB - ESRI Press SN - 978-1-58948-448-1 ER - TY - JOUR TI - Weed Control in Southern Highbush Blueberry with S-metolachlor, Flumioxazin, and Hexazinone AU - Meyers, Stephen L. AU - Jennings, Katherine M. AU - Monks, David W. AU - Ballington, James R. AU - Jordan, David L. T2 - INTERNATIONAL JOURNAL OF FRUIT SCIENCE AB - AbstractField studies were conducted in 2010, 2011, and 2012 at a commercial blueberry farm near Burgaw, NC to determine weed control and crop tolerance to S-metolachlor and flumioxazin alone or mixed with hexazinone. Herbicides were applied pre-budbreak and postharvest. Pre-budbreak applications consisted of hexazinone at 1.1 or 2.2 kg ai ha−1, S-metolachlor at 1.4 or 2.8 kg ai ha–1, and flumioxazin at 215 g ai ha–1 alone and tank mixes of hexazinone or flumioxazin plus S-metolachlor. Additional treatments consisted of flumioxazin (215 g ha–1), flumioxazin plus S-metolachlor (1.4 and 2.8 kg ha–1), or hexazinone (1.1 kg ha–1) plus S-metolachlor (1.4 and 2.8 kg ha–1) applied pre-budbreak and followed by (fb) a postharvest application of flumioxazin (215 g ha–1). Herbicide programs containing flumioxazin resulted in greater Maryland meadowbeauty control (73%) 5 to 6 weeks after treatment (WAT) than herbicide programs containing hexazinone at 1.1 or 2.2 kg ha–1 (37% and 39%, respectively). Needleleaf rosette... DA - 2016/// PY - 2016/// DO - 10.1080/15538362.2015.1072490 VL - 16 IS - 2 SP - 150-158 SN - 1553-8362 KW - Orchard floor management KW - weed control ER - TY - JOUR TI - Response of the Weed Maryland Meadowbeauty (Rhexia mariana L.) and Blueberry to Flumioxazin PRE AU - Coneybeer-Roberts, Meagan M. AU - Jennings, Katherine M. AU - Monks, David W. T2 - INTERNATIONAL JOURNAL OF FRUIT SCIENCE AB - Field studies were conducted in 2007 and 2008 in North Carolina to determine the response of the weed Maryland meadowbeauty and blueberry to flumioxazin PRE (pre-emergence). No injury to non-bearing (blueberry plants not mature enough to produce fruit) or bearing (blueberry plants mature enough to produce fruit) blueberry from flumioxazin PRE was observed. In non-bearing blueberry, control of meadowbeauty was greater than 97% 90 DAT (days after treatment) with the registered rate of 0.42 kg ai ha–1 flumioxazin. Across two studies in bearing blueberry, a single application of flumioxazin at 0.42 kg ai ha–1 controlled meadowbeauty 79% to 92% 90 DAT. Flumioxazin at 0.21 kg ai ha–1 applied twice 60 d apart resulted in greater than 96% meadowbeauty control 90 d after the first application. Treatments of flumioxazin applied as a single application or two applications applied sequentially 60 d apart in bearing blueberry had yields ranging from 3150 to 6065 kg ha–1and 3551 to 5735 kg ha–1, respectively, and did not have a negative effect on blueberry yield regardless of application rate compared to the nontreated check. DA - 2016/// PY - 2016/// DO - 10.1080/15538362.2015.1108895 VL - 16 IS - 3 SP - 301-309 SN - 1553-8362 KW - Herbicide tolerance KW - herbicide efficacy KW - yield ER - TY - JOUR TI - Fruit Quality and Composition of Two Advanced North Carolina Strawberry Selections AU - Perkins-Veazie, Penelope AU - Pattison, Jeremy AU - Fernandez, Gina AU - Ma, Guoying T2 - INTERNATIONAL JOURNAL OF FRUIT SCIENCE AB - The advanced selections, NCS 10-038 and NCS 10-156, from the North Carolina breeding program were compared to the traditionally used cultivars, Camarosa and Chandler, for storage life and fruit composition in 2014 and 2015. Postharvest quality of NCS 10-038 was similar to that of ‘Camarosa’ and ‘Chandler’ after 8 days storage at 4 °C. NCS 10-156 was significantly worse in overall appearance and had more fruit shrivel, calyx browning, and mold than the other genotypes. However, NCS 10-156 was highest in soluble solids content and was similar in total anthocyanin content and total phenolic content to ‘Camarosa’ and ‘Chandler’. Further analysis of flavonoids by high performance liquid chromatography showed that NCS 10-156 was much lower in total flavonols than the other genotypes and comparable in anthocyanin pigments to ‘Chandler’. NCS 10-038, while similar in pigment profile to ‘Camarosa’, had less total anthocyanin than the other genotypes. NCS 10-038 had a lighter red color than the other genotypes and was similar in postharvest quality to ‘Chandler’ and ‘Camarosa’ and may be suitable for long-distance markets. NCS 10-156 is slightly softer than the other genotypes and more prone to mold while the higher soluble solids content may make it suitable for direct market sales. Both selections show postharvest promise for strawberry production in the humid mid-South region. DA - 2016/// PY - 2016/// DO - 10.1080/15538362.2016.1219289 VL - 16 SP - 220-227 SN - 1553-8362 KW - Postharvest KW - phenolics KW - anthocyanin KW - pelargonidin 3-glucoside KW - fruit quality ratings ER - TY - CHAP TI - Cotton Fiber Biotechnology: Potential Controls and Transgenic Improvement of Elongation and Cell Wall Thickening AU - Stiff, Michael R. AU - Tuttle, J. Rich AU - Graham, Benjamin P. AU - Haigler, Candace H. T2 - Fiber Plants A2 - Ramawat, K. A2 - Ahuja, M. T3 - Sustainable Development and Biodiversity AB - Cotton is grown on five continents as an economically important crop. Its long, fine, seed fibers are one of the most highly used natural fibers, providing a high-quality spinnable fiber to the textile industry. The cotton fiberCotton fiber undergoes a complex, staged developmental program, resulting in a single cell that is 1.8–5 cm long with a thick wall composed of about 95 % cellulose. Biotechnological improvements have either directly or indirectly enhanced the fiber properties that are important for spinning, including length, bundle strength, and maturity. These experiments have generally targeted carbohydrate metabolism, cell wall structure, and hormone signaling. In this chapter, we present a brief review of cotton fiber developmentCotton fiber development with a focus on processes affecting elongation and cell wall thickening. We discuss rigorous criteria for evaluating studies on transgenic cotton fiber and mention the challenges of performing such research in the public sector. We highlight selected genetic engineering experiments that have resulted in improved cotton fiber quality Cotton fiber quality and discuss future prospects for use of biotechnology to improve cotton fiberCotton fiber and its competitiveness with synthetic fibers. PY - 2016/// DO - 10.1007/978-3-319-44570-0_8 VL - 13 SP - 127–153 PB - Springer International Publishing SN - 9783319445694 9783319445700 SV - 13 UR - http://dx.doi.org/10.1007/978-3-319-44570-0_8 KW - Cotton fiber development KW - Fiber improvement KW - Fiber quality KW - Primary cell wall KW - Secondary cell wall ER - TY - CONF TI - Manganese removal from New Zealand coal mine drainage using limestone leaching beds AU - Christenson, H. AU - Pope, J. AU - Trumm, D. AU - Uster, B. AU - Newman, N. AU - Young, M. C2 - 2016/// C3 - Mining Meets Water - Conflicts and Solutions DA - 2016/// SP - 906-912 ER - TY - JOUR TI - Comparative diversity analysis of southeastern Rubus germplasm through molecular and pedigree techniques AU - Bradish, C. M. AU - Overbaugh, E. AU - Ballington, J. AU - Fernandez, G. E. AU - Bassil, N. V. T2 - XXIX INTERNATIONAL HORTICULTURAL CONGRESS ON HORTICULTURE: SUSTAINING LIVES, LIVELIHOODS AND LANDSCAPES (IHC2014): INTERNATIONAL SYMPOSIUM ON PLANT BREEDING IN HORTICULTURE DA - 2016/// PY - 2016/// DO - 10.17660/actahortic.2016.1127.25 VL - 1127 SP - 157-161 SN - 2406-6168 KW - fingerprinting KW - Rubus idaeus KW - raspberry KW - black raspberry KW - blackberry KW - SSR markers ER - TY - JOUR TI - The Genetic architecture of quantitative traits cannot be inferred from variance component analysis AU - Huang, W. AU - Mackay, T. F. C. T2 - PLoS Genetics AB - Abstract Classical quantitative genetic analyses estimate additive and non-additive genetic and environmental components of variance from phenotypes of related individuals. The genetic variance components are defined in terms of genotypic values reflecting underlying genetic architecture (additive, dominance and epistatic genotypic effects) and allele frequencies. However, the dependency of the definition of genetic variance components on the underlying genetic models is not often appreciated. Here, we show how the partitioning of additive and non-additive genetic variation is affected by the genetic models and parameterization of allelic effects. We show that arbitrarily defined variance components often capture a substantial fraction of total genetic variation regardless of the underlying genetic architecture in simulated and real data. Therefore, variance component analysis cannot be used to infer genetic architecture of quantitative traits. The genetic basis of quantitative trait variation in a natural population can only be defined empirically using high resolution mapping methods followed by detailed characterization of QTL effects. DA - 2016/// PY - 2016/// DO - 10.1101/041434 VL - 12 IS - 11 ER - TY - JOUR TI - Potential Corn Yield Losses from Weeds in North America AU - Soltani, Nader AU - Dille, J. Anita AU - Burke, Ian C. AU - Everman, Wesley J. AU - VanGessel, Mark J. AU - Davis, Vince M. AU - Sikkema, Peter H. T2 - WEED TECHNOLOGY AB - Crop losses from weed interference have a significant effect on net returns for producers. Herein, potential corn yield loss because of weed interference across the primary corn-producing regions of the United States and Canada are documented. Yield-loss estimates were determined from comparative, quantitative observations of corn yields between nontreated and treatments providing greater than 95% weed control in studies conducted from 2007 to 2013. Researchers from each state and province provided data from replicated, small-plot studies from at least 3 and up to 10 individual comparisons per year, which were then averaged within a year, and then averaged over the seven years. The resulting percent yield-loss values were used to determine potential total corn yield loss in t ha −1 and bu acre −1 based on average corn yield for each state or province, as well as corn commodity price for each year as summarized by USDA-NASS (2014) and Statistics Canada (2015). Averaged across the seven years, weed interference in corn in the United States and Canada caused an average of 50% yield loss, which equates to a loss of 148 million tonnes of corn valued at over U.S.$26.7 billion annually. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-16-00046.1 VL - 30 IS - 4 SP - 979-984 SN - 1550-2740 KW - Best management practices KW - crop losses KW - economic loss KW - herbicides KW - weeds KW - weed management KW - USA KW - Canada ER - TY - JOUR TI - N2O EMISSION AND NITROGEN TRANSFORMATION IN CHICKEN MANURE AND BIOCHAR CO-COMPOSTING AU - Jia, X. AU - Wang, M. AU - Yuan, W. AU - Shah, S. AU - Shi, W. AU - Meng, X. AU - Ju, X. AU - Yang, B. T2 - TRANSACTIONS OF THE ASABE AB - This study examined the effect of biochar addition on nitrous oxide (N2O) emission and nitrogen (N) transformation in co-composting of biochar and chicken manure. Compared with the control (no biochar), addition of 20% biochar resulted in a 59.8% decrease in the major peak of N2O emission. Ammonium (NH4+-N) and nitrate (NO3--N) contents in the final product with 20% biochar addition increased by 67.3% and 66.7%, respectively, compared to the control. Turning frequency (TF), the primary parameter of aeration and temperature control in the biochar-manure co-composting process, was also investigated. Results indicated that less frequent turning (e.g., turning every seven days) promoted NH4+-N and NO3-N retention but increased peak N2O emission by 58.1% compared with daily turning. Overall, biochar can be an ideal bulking agent for stabilizing N-rich materials to minimize N2O emission and, with proper aeration, can enhance nitrogen retention based on this laboratory study. DA - 2016/// PY - 2016/// DO - 10.13031/trans.59.11685 VL - 59 IS - 5 SP - 1277-1283 SN - 2151-0040 KW - Biochar KW - Chicken manure KW - Co-composting KW - N2O emission KW - Nitrogen transformation ER - TY - JOUR TI - Leaf pubescence and defoliation strategy influence on cotton defoliation and fiber quality AU - Byrd, S. A. AU - Collins, G. D. AU - Edmisten, K. L. AU - Roberts, P. M. AU - Snider, J. L. AU - Spivey, T. A. AU - Whitaker, J. R. AU - Porter, W. M. AU - Culpepper, A. S. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 4 SP - 280-293 ER - TY - JOUR TI - Integrating fluridone into a glufosinate-based program for Palmer amaranth control in cotton AU - Braswell, L. R. AU - Cahoon, C. W. AU - Seagroves, R. W. AU - Jordan, D. L. AU - York, A. C. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 4 SP - 394-402 ER - TY - JOUR TI - In Situ Thermistor Calibration for Improved Measurement of Soil Temperature Gradients AU - Kool, Dilia AU - Heitman, Joshua L. AU - Lazarovitch, Naftali AU - Agam, Nurit AU - Sauer, Thomas J. AU - Ben-Gal, Alon T2 - Soil Science Society of America Journal AB - Core Ideas Soil temperature gradients are important for soil (latent) heat flux estimation. Heat‐pulse sensor thermistors' temperature differences were on the order of 0.2°C. In situ calibration reduced uncertainty between thermistors to about 0.06°C. In situ calibrated offsets between thermistors were similar to laboratory results. Offsets were found to change very little over a 5‐yr period. Accurate measurement of soil temperature gradients is important for the estimation of soil heat flux and latent heat flux, both major components of the surface energy balance. Soil temperature gradients are commonly measured using heat‐pulse sensors equipped with thermistors. In this study, individual thermistors showed absolute temperature differences on the order of 0.2°C when placed under uniform temperature conditions. These differences compromised measurement of soil temperature gradients over small depth increments and/or conditions with relatively minor variation in temperatures. An in situ calibration approach was found to reduce the uncertainty between thermistors to about 0.05°C in a vineyard under arid conditions. In situ calibration results were similar to laboratory results before and after field deployment for temperatures ranging between 4 and 60°C. Thermistor offsets were found to change very little over a 5‐yr period, indicating that pre‐ or post‐laboratory calibration could be sufficient. The in situ approach can be useful when calibration prior to field deployment is unavailable and/or sensor failure prevents post‐field calibration. DA - 2016/11// PY - 2016/11// DO - 10.2136/sssaj2016.05.0134 VL - 80 IS - 6 SP - 1514-1519 J2 - Soil Science Society of America Journal LA - en OP - SN - 0361-5995 UR - http://dx.doi.org/10.2136/sssaj2016.05.0134 DB - Crossref ER - TY - JOUR TI - Comparing Dislodgeable 2,4-D Residues across Athletic Field Turfgrass Species and Time AU - Jeffries, Matthew D. AU - Gannon, Travis W. AU - Brosnan, James T. AU - Breeden, Gregory K. T2 - PLOS ONE AB - 2,4-dimethylamine salt (2,4-D) is an herbicide commonly applied on athletic fields for broadleaf weed control that can dislodge from treated turfgrass. Dislodge potential is affected by numerous factors, including turfgrass canopy conditions. Building on previous research confirming herbicide-turfgrass dynamics can vary widely between species, field research was initiated in 2014 and 2015 in Raleigh, NC, USA to quantify dislodgeable 2,4-D residues from dormant hybrid bermudagrass (Cynodon dactylon L. x C. transvaalensis) and hybrid bermudagrass overseeded with perennial ryegrass (Lolium perenne L.), which are common athletic field playing surfaces in subtropical climates. Additionally, dislodgeable 2,4-D was compared at AM (7:00 eastern standard time) and PM (14:00) sample timings within a day. Samples collected from perennial ryegrass consistently resulted in greater 2,4-D dislodgment immediately after application (9.4 to 9.9% of applied) compared to dormant hybrid bermudagrass (2.3 to 2.9%), as well as at all AM compared to PM timings from 1 to 3 d after treatment (DAT; 0.4 to 6.3% compared to 0.1 to 0.8%). Dislodgeable 2,4-D did not differ across turfgrass species at PM sample collections, with ≤ 0.1% of the 2,4-D applied dislodged from 1 to 6 DAT, and 2,4-D detection did not occur at 12 and 24 DAT. In conclusion, dislodgeable 2,4-D from treated turfgrass can vary between species and over short time-scales within a day. This information should be taken into account in human exposure risk assessments, as well as by turfgrass managers and athletic field event coordinators to minimize 2,4-D exposure. DA - 2016/12/9/ PY - 2016/12/9/ DO - 10.1371/journal.pone.0168086 VL - 11 IS - 12 SP - SN - 1932-6203 ER - TY - JOUR TI - The Genetics of Leaf Flecking in Maize and Its Relationship to Plant Defense and Disease Resistance AU - Olukolu, Bode A. AU - Bian, Yang AU - De Vries, Brian AU - Tracy, William F. AU - Wisser, Randall J. AU - Holland, James B. AU - Balint-Kurti, Peter J. T2 - PLANT PHYSIOLOGY AB - Physiological leaf spotting, or flecking, is a mild-lesion phenotype observed on the leaves of several commonly used maize (Zea mays) inbred lines and has been anecdotally linked to enhanced broad-spectrum disease resistance. Flecking was assessed in the maize nested association mapping (NAM) population, comprising 4,998 recombinant inbred lines from 25 biparental families, and in an association population, comprising 279 diverse maize inbreds. Joint family linkage analysis was conducted with 7,386 markers in the NAM population. Genome-wide association tests were performed with 26.5 million single-nucleotide polymorphisms (SNPs) in the NAM population and with 246,497 SNPs in the association population, resulting in the identification of 18 and three loci associated with variation in flecking, respectively. Many of the candidate genes colocalizing with associated SNPs are similar to genes that function in plant defense response via cell wall modification, salicylic acid- and jasmonic acid-dependent pathways, redox homeostasis, stress response, and vesicle trafficking/remodeling. Significant positive correlations were found between increased flecking, stronger defense response, increased disease resistance, and increased pest resistance. A nonlinear relationship with total kernel weight also was observed whereby lines with relatively high levels of flecking had, on average, lower total kernel weight. We present evidence suggesting that mild flecking could be used as a selection criterion for breeding programs trying to incorporate broad-spectrum disease resistance. DA - 2016/11// PY - 2016/11// DO - 10.1104/pp.15.01870 VL - 172 IS - 3 SP - 1787-1803 SN - 1532-2548 UR - https://doi.org/10.1104/pp.15.01870 ER - TY - JOUR TI - Population Dynamics Among six Major Groups of the Oryza rufipogon Species Complex, Wild Relative of Cultivated Asian Rice AU - Kim, HyunJung AU - Jung, Janelle AU - Singh, Namrata AU - Greenberg, Anthony AU - Doyle, Jeff J. AU - Tyagi, Wricha AU - Chung, Jong-Wook AU - Kimball, Jennifer AU - Hamilton, Ruaraidh Sackville AU - McCouch, Susan R. T2 - RICE AB - Understanding population structure of the wild progenitor of Asian cultivated rice (O. sativa), the Oryza rufipogon species complex (ORSC), is of interest to plant breeders and contributes to our understanding of rice domestication. A collection of 286 diverse ORSC accessions was evaluated for nuclear variation using genotyping-by-sequencing (113,739 SNPs) and for chloroplast variation using Sanger sequencing (25 polymorphic sites). Six wild subpopulations were identified, with 25 % of accessions classified as admixed. Three of the wild groups were genetically and geographically closely related to the O. sativa subpopulations, indica, aus and japonica, and carried O. sativa introgressions; the other three wild groups were genetically divergent, had unique chloroplast haplotypes, and were located at the geographical extremes of the species range. The genetic subpopulations were significantly correlated (r 2 = 0.562) with traditional species designations, O. rufipogon (perennial) and O. nivara (annual), differentiated based on morphology and life history. A wild diversity panel of 95 purified (inbred) accessions was developed for future genetic studies. Our results suggest that the cultivated aus subpopulation is most closely related to an annual wild relative, japonica to a perennial wild relative, and indica to an admixed population of diverse annual and perennial wild ancestors. Gene flow between ORSC and O. sativa is common in regions where rice is cultivated, threatening the identity and diversity of wild ORSC populations. The three geographically isolated ORSC populations harbor variation rarely seen in cultivated rice and provide a unique window into the genetic composition of ancient rice subpopulations. DA - 2016/10/12/ PY - 2016/10/12/ DO - 10.1186/s12284-016-0119-0 VL - 9 SP - SN - 1939-8433 KW - Population Structure KW - Domestication KW - Annual-Perennial KW - Chloroplast Diversity KW - Phylogeography ER - TY - JOUR TI - Greenhouse Gas Emissions from a Created Brackish Marsh in Eastern North Carolina AU - Shiau, Yo-Jin AU - Burchell, Michael R. AU - Krauss, Ken W. AU - Birgand, Francois AU - Broome, Stephen W. T2 - WETLANDS DA - 2016/12// PY - 2016/12// DO - 10.1007/s13157-016-0815-y VL - 36 IS - 6 SP - 1009-1024 SN - 1943-6246 KW - Brackish marsh creation KW - Greenhouse gas emission KW - Carbon dioxide KW - Methane KW - Carbon sequestration ER - TY - JOUR TI - Fecal contamination and Microcystis in drinking-water sources of rural Cambodia using PCR and culture-based methods AU - Matteson, Audrey R. AU - Graves, Alexandria K. AU - Hall, Ann M. AU - Kuy, Dina AU - Polizzotto, Matthew L. T2 - JOURNAL OF WATER SANITATION AND HYGIENE FOR DEVELOPMENT AB - Rural communities within low-income countries frequently rely on a range of drinking-water sources, and each water source varies in its potential for biological contamination. The extent and source of biological contamination in primary drinking sources within Kien Svay, Kandal, Cambodia, were determined by fecal indicator bacteria (FIB) measurements, 16S rDNA genetic markers for human and bovine fecal Bacteroides, presence of the bloom-forming Microcystis species, and the microcystin toxin mcyD gene marker. Thirteen wells, 11 rain barrels, 10 surface-water sites, and five sediment samples were examined during the dry and wet seasons. Surface water was commonly contaminated with FIB, with up to 1.02 × 105Enterococcus sp., 6.13 × 104E. coli, and 2.91 × 104 total coliforms per 100 mL of water. Human and bovine Bacteroides were detected in 100 and 90% of the surface water samples, respectively. Concentrations of FIB in rain-barrels varied by site, however 91% contained human Bacteroides. Microcystis cells were found in 90% of surface water sites, with many also containing microcystin gene mcyD, representing the first report of microcystin-producing cyanobacteria in surface waters of Cambodia. The study results show that many potential drinking-water sources in Cambodia contain harmful bacterial and algal contaminants, and care should be taken when selecting and monitoring water options. DA - 2016/9// PY - 2016/9// DO - 10.2166/washdev.2016.136 VL - 6 IS - 3 SP - 353-361 SN - 2043-9083 KW - Bacteroides KW - Cambodia KW - coliforms KW - Enterococcus KW - fecal pollution KW - water ER - TY - JOUR TI - Black raspberry fruit composition over two years from seedling populations grown at four US geographic locations AU - Perkins-Veaziel, P. AU - Ma, G. AU - Fernandez, G. E. AU - Bradish, C. M. AU - Bushakra, J. M. AU - Bassil, N. V. AU - Weber, C. A. AU - Scheerens, J. C. AU - Robbins, L. AU - Finn, C. E. AU - Dossett, M. T2 - XI INTERNATIONAL RUBUS AND RIBES SYMPOSIUM DA - 2016/// PY - 2016/// DO - 10.17660/actahortic.2016.1133.52 VL - 1133 SP - 335-338 SN - 0567-7572 ER - TY - JOUR TI - Evaluation of Wick-Applied Glyphosate for Palmer Amaranth (Amaranthus palmeri) Control in Sweetpotato AU - Meyers, Stephen L. AU - Jennings, Katherine M. AU - Schultheis, Jonathan R. AU - Monks, David W. T2 - WEED TECHNOLOGY AB - Studies were conducted in 2007 and 2008 at Clinton, NC to determine the effect of glyphosate applied POST via a Dixie wick applicator on Palmer amaranth control and sweetpotato yield and quality. In 2007, treatments consisted of glyphosate wicked sequentially 6 and 8 wk after transplanting (WAP) and glyphosate wicked sequentially 6 and 8 WAP followed by (fb) rotary mowing 9 WAP. In 2008, treatments consisted of glyphosate wicked once 4 or 7 WAP, wicked sequentially 4 and 7 WAP, mowed once 4 WAP, and mowed 4 WAP fb wicking 7 WAP. In 2008, Palmer amaranth control 6 WAP varied by location and averaged 10 and 58% for plots wicked 4 WAP. Palmer amaranth contacted by the wicking apparatus were controlled, but weeds shorter than the wicking height escaped treatment. Palmer amaranth control 9 WAP was greater than 90% for all treatments wicked 7 WAP. Competition prior to and between glyphosate treatments contributed to large sweetpotato yield losses. Treatments consisting of glyphosate 7 or 8 WAP (in 2007 and 2008, respectively) frequently had greater no. 1 and marketable yields compared to the weedy control. However, jumbo, no. 1, and marketable yields for all glyphosate and mowing treatments were generally less than half the hand-weeded check. Cracked sweetpotato roots were observed in glyphosate treatments and percent cracking (by weight) in those plots ranged from 1 to 12% for no. 1 roots, and 1 to 6% for marketable roots. Findings from this research suggest wicking might be useful in a salvage scenario, but only after currently registered preemergence herbicides and between-row cultivation have failed to control Palmer amaranth and other weed species below the sweetpotato canopy. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-16-00024.1 VL - 30 IS - 3 SP - 765-772 SN - 1550-2740 KW - Root cracking KW - wick applicator ER - TY - JOUR TI - Evaluation of Herbicide Timings for Palmer Amaranth Control in a Stale Seedbed Sweetpotato Production System AU - Coleman, Lauren B. AU - Chaudhari, Sushila AU - Jennings, Katherine M. AU - Schultheis, Jonathan R. AU - Meyers, Stephen L. AU - Monks, David W. T2 - WEED TECHNOLOGY AB - Studies were conducted in a stale field production system in 2012 and 2013 to determine the effect of herbicide timing on Palmer amaranth control and ‘Covington’ sweetpotato yield and quality. Treatments consisted of flumioxazin at 72, 90, or 109 g ai ha −1 applied 45 d before transplanting (DBT) or 1 DBT, or sequentially the same rate at 45 DBT followed by (fb) 1 DBT; flumioxazin 109 g ha −1 applied 1 DBT fb S -metolachlor (800 g ai ha −1 ) at 0, 6 (± 1), or 10 d after treatment (DAT); flumioxazin at 72, 90, or 109 g ha −1 plus clomazone (630 g ai ha −1 ) applied 45 DBT fb S -metolachlor (800 g ha −1 ) applied 10 DAT; and fomesafen alone at 280 g ai ha −1 applied 45 DBT. Nontreated weed-free and weedy controls were included for comparison. Flumioxazin application time had a significant effect on Palmer amaranth control and sweetpotato yields, and the effect of flumioxazin rate was not significant. Treatments consisting of sequential application of flumioxazin 45 DBT fb 1 DBT or flumioxazin plus clomazone 45 DBT fb S -metolachlor 10 DAT provided the maximum Palmer amaranth control and sweetpotato yields (jumbo, No. 1, jumbo plus No. 1, marketable) among all treatments. Delayed flumioxazin application timings until 1 DBT allowed Palmer amaranth emergence on stale seedbeds and resulted only in 65, 62, 48, and 17% control at 14, 32, 68, and 109 DAT, respectively. POST transplant S -metolachlor applications following flumioxazin 1 DBT did not improve Palmer amaranth control, because the majority of Palmer amaranth emerged prior to S -metolachlor application. A control program consisting of flumioxazin 109 g ha −1 plus clomazone 630 g ha −1 at 45 DBT fb S -metolachlor 800 g ha −1 at 0 to 10 DAT provides an effective herbicide program for Palmer amaranth control in stale seedbed production systems in North Carolina sweetpotato. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00133.1 VL - 30 IS - 3 SP - 725-732 SN - 1550-2740 KW - Weed control KW - yield loss ER - TY - JOUR TI - Effect of Soil Organic Matter Content and Volumetric Water Content on 'Tifway 419' Hybrid Bermudagrass Growth Following Indaziflam Applications AU - Jeffries, Matthew D. AU - Gannon, Travis W. T2 - WEED TECHNOLOGY AB - Indaziflam is a cellulose biosynthesis–inhibiting herbicide for PRE annual weed control in turfgrass systems. Since indaziflam's 2010 U.S. registration, sporadic cases of hybrid bermudagrass injury have been reported; however, causes are not well understood. Field research was conducted from 2013 to 2015 on sandy soil to elucidate the effects of soil organic matter content (SOMC) and soil volumetric water content (SVWC) on plant growth following indaziflam application on established or root-compromised (5 cm long) hybrid bermudagrass. The effect of SOMC was evaluated at two levels, 1.4 (low) and 5.5% (high) w/w at the soil surface (0 to 2.5 cm depth), whereas SVWC was evaluated PRE (2 wk before) and POST (6 wk after) indaziflam application at two levels (low or high). Indaziflam was applied (50 or 100 g ai ha −1 ) at fall-only, fall-plus-spring, and spring-only timings. Regardless of application timing or SVWC, indaziflam applied at 50 g ha −1 to high SOMC did not cause > 10% visual cover reduction on established or root-compromised hybrid bermudagrass. Indaziflam applied to hybrid bermudagrass on low SOMC exacerbated adverse growth effects, most notably when root systems were compromised before application. Overall, PRE indaziflam application SVWC did not affect hybrid bermudagrass growth. Within low SOMC, low POST indaziflam application SVWC caused less visual hybrid bermudagrass cover reduction than did high POST indaziflam application SVWC, whereas both fall-plus-spring and spring-only application timings caused similarly greater reductions than fall-only indaziflam application. Data from this research will aid turfgrass managers to effectively use indaziflam without adversely affecting hybrid bermudagrass growth. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00192.1 VL - 30 IS - 3 SP - 677-687 SN - 1550-2740 KW - Best management practice KW - cellulose biosynthesis inhibition KW - herbicide injury KW - normalized difference vegetation index KW - visual cover ER - TY - JOUR TI - Detection of N2O-producing fungi in environment using nitrite reductase gene (nirK)-targeting primers AU - Chen, H. H. AU - Yu, F. B. AU - Shi, Wei T2 - Fungal Biology AB - Fungal denitrification has been increasingly investigated, but its community ecology is poorly understood due to the lack of culture-independent tools. In this work, four pairs of nirK-targeting primers were designed and evaluated for primer specificity and efficiency using thirty N2O-producing fungal cultures and an agricultural soil. All primers amplified nirK from fungi and soil, but their efficiency and specificity were different. A primer set, FnirK_F3/R2 amplified ∼80 % of tested fungi, including Aspergillus, Fusarium, Penicillium, and Trichoderma, as compared to ∼40-70 % for other three primers. The nirK fragments of fungal and soil DNA amplified by FnirK_F3/R2 were phylogenetically related to denitrifying fungi in the orders Eurotiales, Hypocreales, and Sordariales; and clone sequences were also distributed in the clusters of Chaetomium, Metarhizium, and Myceliophthora that were uncultured from soil in our previous work. This proved the wide-range capability of primers for amplifying diverse denitrifying fungi from environment. However, our primers and recently-developed other primers amplified bacterial nirK from soil and this co-amplification of fungal and bacterial nirK was theoretically discussed. The FnirK_F3/R2 was further compared with published primers; results from clone libraries demonstrated that FnirK_F3/R2 was more specifically targeted on fungi and had broader taxonomical coverage than some others. DA - 2016/// PY - 2016/// DO - 10.1016/j.funbio.2016.07.012 VL - 120 IS - 12 SP - 1479–1492 ER - TY - JOUR TI - Cotton Stage of Growth Determines Sensitivity to 2,4-D AU - Byrd, Seth A. AU - Collins, Guy D. AU - Culpepper, A. Stanley AU - Dodds, Darrin M. AU - Edmisten, Keith L. AU - Wright, David L. AU - Morgan, Gaylon D. AU - Baumann, Paul A. AU - Dotray, Peter A. AU - Manuchehri, Misha R. AU - Jones, Andrea AU - Grey, Timothy L. AU - Webster, Theodore M. AU - Davis, Jerry W. AU - Whitaker, Jared R. AU - Roberts, Phillip M. AU - Snider, John L. AU - Porter, Wesley M. T2 - WEED TECHNOLOGY AB - The anticipated release of Enlist TM cotton, corn, and soybean cultivars likely will increase the use of 2,4-D, raising concerns over potential injury to susceptible cotton. An experiment was conducted at 12 locations over 2013 and 2014 to determine the impact of 2,4-D at rates simulating drift (2 g ae ha −1 ) and tank contamination (40 g ae ha −1 ) on cotton during six different growth stages. Growth stages at application included four leaf (4-lf), nine leaf (9-lf), first bloom (FB), FB + 2 wk, FB + 4 wk, and FB + 6 wk. Locations were grouped according to percent yield loss compared to the nontreated check (NTC), with group I having the least yield loss and group III having the most. Epinasty from 2,4-D was more pronounced with applications during vegetative growth stages. Importantly, yield loss did not correlate with visual symptomology, but more closely followed effects on boll number. The contamination rate at 9-lf, FB, or FB + 2 wk had the greatest effect across locations, reducing the number of bolls per plant when compared to the NTC, with no effect when applied at FB + 4 wk or later. A reduction of boll number was not detectable with the drift rate except in group III when applied at the FB stage. Yield was influenced by 2,4-D rate and stage of cotton growth. Over all locations, loss in yield of greater than 20% occurred at 5 of 12 locations when the drift rate was applied between 4-lf and FB + 2 wk (highest impact at FB). For the contamination rate, yield loss was observed at all 12 locations; averaged over these locations yield loss ranged from 7 to 66% across all growth stages. Results suggest the greatest yield impact from 2,4-D occurs between 9-lf and FB + 2 wk, and the level of impact is influenced by 2,4-D rate, crop growth stage, and environmental conditions. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00191.1 VL - 30 IS - 3 SP - 601-610 SN - 1550-2740 KW - Crop maturity KW - Enliste (TM) technology KW - epinasty KW - boll distribution ER - TY - JOUR TI - Power Tuning HPC Jobs on Power-Constrained Systems AU - Gholkar, Neha AU - Mueller, Frank AU - Rountree, Barry T2 - 2016 INTERNATIONAL CONFERENCE ON PARALLEL ARCHITECTURE AND COMPILATION TECHNIQUES (PACT) AB - As we approach the exascale era, power has become a primary bottleneck. The US Department of Energy has set a power constraint of 20MW on each exascale machine. To be able achieve one exaflop under this constraint, it is necessary that we use power intelligently to maximize performance under a power constraint. DA - 2016/// PY - 2016/// DO - 10.1145/2967938.2967961 SP - 179-190 ER - TY - JOUR TI - Major Leaf Shape Genes, Laciniate in Diploid Cotton and Okra in Polyploid Upland Cotton, Map to an Orthologous Genomic Region AU - Kaur, Baljinder AU - Andres, Ryan AU - Kuraparthy, Vasu T2 - CROP SCIENCE AB - Gossypium arboreum L, which produces spinnable cotton fibers, is an A‐genome diploid progenitor species of tetraploid cotton. With its diploid genome, publicly available genome sequence, adapted growth, and developmental and agronomic attributes, G. arboreum could make an ideal cotton species to study the genetic basis of biological traits that are controlled by orthologous loci in diploid and polyploid species. Leaf shape is an important agronomic trait in cotton. Normal, subokra, okra, and laciniate are the predominant leaf shapes in cotton cultivars. Laciniate in diploids is phenotypically similar to okra leaf shape in tetraploid. In the present study, a population of 135 F 2 plants derived from accessions NC 501 and NC 505 was used for genetic and molecular mapping of laciniate leaf shape in diploid cotton ( G. arboreum ). An inheritance study showed that laciniate leaf shape was controlled by a single incompletely dominant gene ( L L –A 2 ). Molecular genetic mapping using simple‐sequence repeat (SSR) markers placed the leaf shape locus L‐A 2 on chromosome 2. Targeted mapping using putative genes from the delineated region established that laciniate leaf shape in G. arboreum and okra leaf shape in Gossypium hirsutum L. were controlled by genes at orthologous loci. Collinearity was well conserved between the diploid A‐ ( G. arboreum ) and D‐ ( G. raimondii Ulbr.) genomes in the targeted genomic region narrowing the candidate region for the leaf shape locus ( L‐A 2 ) to nine putative genes. Establishing the orthologous genomic region for the L loci could help use the diploid cotton resources toward map‐based cloning of leaf shape genes in Gossypium . DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.10.0627 VL - 56 IS - 3 SP - 1095-1105 SN - 1435-0653 ER - TY - JOUR TI - Cotton fiber tips have diverse morphologies and show evidence of apical cell wall synthesis AU - Stiff, Michael R. AU - Haigler, Candace H. T2 - SCIENTIFIC REPORTS AB - Abstract Cotton fibers arise through highly anisotropic expansion of a single seed epidermal cell. We obtained evidence that apical cell wall synthesis occurs through examining the tips of young elongating Gossypium hirsutum ( Gh ) and G. barbadense ( Gb ) fibers. We characterized two tip types in Gh fiber ( hemisphere and tapered ), each with distinct apical diameter, central vacuole location, and distribution of cell wall components. The apex of Gh hemisphere tips was enriched in homogalacturonan epitopes, including a relatively high methyl-esterified form associated with cell wall pliability. Other wall components increased behind the apex including cellulose and the α-Fuc-(1,2)-β-Gal epitope predominantly found in xyloglucan. Gb fibers had only one narrow tip type featuring characters found in each Gh tip type. Pulse-labeling of cell wall glucans indicated wall synthesis at the apex of both Gh tip types and in distal zones. Living Gh hemisphere and Gb tips ruptured preferentially at the apex upon treatment with wall degrading enzymes, consistent with newly synthesized wall at the apex. Gh tapered tips ruptured either at the apex or distantly. Overall, the results reveal diverse cotton fiber tip morphologies and support primary wall synthesis occurring at the apex and discrete distal regions of the tip. DA - 2016/6/15/ PY - 2016/6/15/ DO - 10.1038/srep27883 VL - 6 SP - SN - 2045-2322 ER - TY - CONF TI - A Computational study of thin film dynamics on micro structured surfaces AU - Lin, L. Y. AU - Dinh, N. T. AU - Sampath, R. AU - Akinci, N. AB - The present study is motivated by interest in understanding of physical mechanisms that govern the effect of material and micro-structural characteristics of heat surface on boiling heat transfer and burnout at high heat fluxes. The effect was reported and investigated experimentally and analytically over several past decades. Only recently, with the advent of nanotechnology including microscale manufacturing, it becomes possible to perform high heat-flux boiling experiments with control of surface conditions. Of particular importance for practice is the potential for significant enhancement of boiling heat transfer (BHT) and critical heat flux (CHF) in pool and flow boiling on heaters with specially manufactured and controlled micro-structured surfaces. This enhancement is very important to a very wide range of engineering applications, like heat exchanger and cooling system, where maximum flux is needed. Currently, there are many controlled experiments that investigate such effect and they lend themselves a subject for detailed computational analysis. The focus of this study is micro-hydrodynamics of the evaporating thin liquid film at the receding triple contact line, corresponding to formation of dry spot in the footprint of a growing bubble. Parametric investigations are performed to assess the hypotheses that micro-structured surfaces enhance resilience to burnout due to residual liquid in the dry patch after contact line receding. Towards the study objective, a particle-based (mesh-less) method of computational fluid dynamics called Smoothed Particle Hydrodynamics (SPH) is adopted. The SPH method is selected for its capability to handle fluid dynamics in complex geometries and free surface problems without mass loss (characteristic of alternative interface capturing schemes used in mesh-based methods). Both surface tension and surface adhesion (hydrophilicity) are implemented and tested. The solid (heater) surface and manufactured micro-structures are represented by solid-type particles. Heat transfer, phase change (evaporation) and vapor dynamics are not included in the present simulation. The bouncing drop case measures the contact time of water droplet with solid surface. This case is used for “mesh” sensitivity (particle size) study and calibration of boundary conditions and surface tension coefficient. Subsequently, case studies are formulated and performed for contact line dynamics on heater surfaces with the fabricated Micro Pillar Arrays surfaces (MPA) and smooth surface. Variable characteristics include surface tension and pillar density on structured surface (modified by changing distance between pillars). First of all, residual fluid are found in all simulations with structured surface, while fluid are drained for smooth cases. For structured surface, it’s found that after the contact line recedes, fluid with higher surface tension resides in the dry patch more than fluid with lower coefficient, and the relation tends to be non-linear. While for smooth surface, all fluid will be drained after certain time and the relations are non-monotonic; it’s also found that the amount of residual fluid increase as the distance between pillars decreases until a limit. The fluid then starts to decrease with pillars being set further apart. The increase starts from 30 μm and the limit is around 10 μm. C2 - 2016/// C3 - Proceedings of the Asme Summer Heat Transfer Conference, 2016, vol 2 DA - 2016/// DO - 10.1115/ht2016-7382 ER - TY - JOUR TI - Weed suppression and soybean yield in a no-till cover-crop mulched system as influenced by six rye cultivars AU - Wells, M. Scott AU - Brinton, Carrie M. AU - Reberg-Horton, S. Chris T2 - RENEWABLE AGRICULTURE AND FOOD SYSTEMS AB - Abstract Cover crop mulches have been successful in reducing weed severity in organic soybeans. This study examined six rye cultivars (SRCs) used as cover crops to determine which were most adapted for use with a roller–crimper in the southeastern U.S. To be an effective mulch, a rye cultivar must produce high biomass and reach reproductive growth stage to facilitate mechanical termination via the roller–crimper prior to soybean planting. Rye cultivars were planted at three locations in North Carolina over the 2009 and 2010 growing seasons. Each rye cultivar was mechanically terminated via a roller–crimper implement. Rye cover crops were terminated on two dates and soybeans were immediately no-till planted into the mulch. In 2009, all rye cultivars produced greater than 9000 kg ha −1 rye biomass dry matter (DM) with the exception of Rymin at Plymouth (2009), but in 2010 only the early flowering cultivars produced in excess of 9000 kg ha −1 DM. There were no detectable soybean yield differences between the SRCs and the weed-free checks, and weed control was excellent across all SRCs at both Plymouth and Salisbury (2009). After an unseasonably cold and wet winter in 2010, the late flowering rye cultivars were not fully controlled by the early termination date due to delayed maturation (less than 65% control at 2 WAP) whereas the early flowering cultivars were fully controlled (100% control at 2 WAP). Rye biomass production was below 9000 kg ha −1 DM for the late flowering and dough development rye cultivars. The early-terminated rye plots had greater weed coverage across all SRCs than those from the late termination date ( P < 0.01). However, weeds did not impact soybean yield for either of the termination dates. Soybean yield in 2010 was modeled with rye biomass and soybean population used as covariates, and for both termination dates, soybean yield was proportional to rye biomass production. Early flowering rye cultivars offer producers the widest range of termination opportunities that best coincide with their cash crop planting dates. DA - 2016/10// PY - 2016/10// DO - 10.1017/s1742170515000344 VL - 31 IS - 5 SP - 429-440 SN - 1742-1713 KW - Cereal rye KW - conservation-tillage KW - no-till KW - cover crop KW - mulch KW - organic KW - rolled-crimped KW - rotational no-till KW - roller-crimper KW - soybean ER - TY - JOUR TI - The use of obsolete and modern cultivars to examine advances in yield and dry matter partitioning AU - Wells, R. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 3 SP - 246-252 ER - TY - JOUR TI - Susceptibility of Dent-Sterile Popcorn to the Ga1-m Gametophyte Factor AU - Jones, Zachary G. AU - Goodman, Major M. T2 - CROP SCIENCE AB - The Ga1‐s allele is the foundation of dent‐sterile popcorn ( Zea mays L. var. everta ), where it is used as a genetic barrier to prevent pollen contamination, but its known genetic susceptibility to another allele at the same locus is problematic for the sustainability of Ga1‐s popcorn. The Ga1‐m allele overcomes the pollen barrier imparted by Ga1‐s , opening any system using it to potential contamination. The Ga1‐m allele, although previously thought rare, has been shown to be abundant in Mexican commercial maize ( Z. mays L.), and has been identified in a US ex‐Plant Variety Protection (PVP) line. The requirement for specific evaluation to detect the allele, coupled with efforts to increase the genetic base of maize, create a considerable risk of the unintentional release of Ga1‐m ‐carrying materials. Resistance to Ga1‐m has been previously identified, providing a possible way to eliminate the risk posed by Ga1‐m but comes in an unadapted sweetcorn background. Through field evaluation, we tested commercial and publically available popcorn for resistance to Ga1‐m , all of which were uniformly susceptible. There is, therefore, a need to identify and integrate Ga1‐m resistance into commercial popcorn inbred lines and hybrids. Although the use of existing Ga1‐m resistant sources is an option, background differences will likely be problematic for producing useable inbred lines. We suggest the use of molecular tools to aid in specific backcrossing of the Ga1‐m resistance allele or identification of Ga1‐m resistance in a popcorn background, for which we suggest an evolutionary‐based approach. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.02.0101 VL - 56 IS - 5 SP - 2594-2599 SN - 1435-0653 ER - TY - JOUR TI - Surfactant-Modified Soil Amendments Reduce Nitrogen and Phosphorus Leaching in a Sand-Based Rootzone AU - Shaddox, Travis W. AU - Kruse, Jason K. AU - Miller, Grady L. AU - Nkedi-Kizza, Peter AU - Sartain, Jerry B. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - United States Golf Association putting greens are susceptible to nitrogen (N) and phosphorus (P) leaching. Inorganic soil amendments are used to increase moisture and nutrient retention and may influence N and P leaching. This study was conducted to determine whether N and P leaching could be reduced using soil amendments and surfactant-modified soil amendments. Treatments included a control (sand), sand-peat, zeolite, calcined clay, hexadecyltrimethylammonium-zeolite, and hexadecyltrimethylammonium-calcined clay. Lysimeters were filled with a 30-cm rootzone layer of sand-peat (85:15 by volume), below which a 5-cm treatment layer of amendments was placed. A solution of NO-N, NH-N, and orthophosphate-P (2300, 2480, and 4400 μg mL, respectively) was injected at the top of each lysimeter, and leachate was collected using an autocollector set to collect a 10-mL sample every min until four pore volumes were collected. Uncoated amendments, sand, and peat had no influence on NO-N retention, whereas hexadecyltrimethylammonium-coated amendments reduced NO-N leaching to below detectable limits. Both coated and uncoated amendments reduced NH-N leaching, with zeolite reducing NH-N leached to near zero regardless of hexadecyltrimethylammonium coating. Pure sand resulted in a 13% reduction of applied orthophosphate-P leaching, whereas peat contributed to orthophosphate-P leaching. Surfactant-modified amendments reduced orthophosphate-P leaching by as much as 97%. Surfactant-modified soil amendments can reduce NO-N, NH-N, and orthophosphate-P leaching and, thus, may be a viable option for removing leached N and P before they enter surface or ground waters. DA - 2016/// PY - 2016/// DO - 10.2134/jeq2016.01.0025 VL - 45 IS - 5 SP - 1549-1556 SN - 1537-2537 ER - TY - JOUR TI - Sowing Density Effect on Common Bean Leaf Area Development AU - Ricaurte, Jaumer AU - Michelangeli, Jose A. Clavijo AU - Sinclair, Thomas R. AU - Rao, Idupulapati M. AU - Beebe, Stephen E. T2 - CROP SCIENCE AB - Sowing density is a major management factor that affects growth and development of grain crops by modifying the canopy light environment and interplant competition for water and nutrients. While the effects of density and plant architecture on static vegetative and reproductive growth traits have been explored previously in common bean ( Phaseolus vulgaris L.), there are no reports of intensive measurements of the temporal dynamics on node addition and leaf area development. Such results are reported here from two sites of field experiments where the effects of sowing densities (5, 10, 15, 20, 25, and 35 plants m −2 ) and genotypes with contrasting plant architectures (two each from growth habits I, II, and III) were assessed. Analysis of the phyllochron (°C node −1 ) indicated genotype and density effects (but no interaction) on the rate of node addition. While significant, these differences amounted to <2 d of leaf development at either site. In terms of leaf area development, analysis using a power function reflected large differences in the dynamics and final size of individual plant leaf area (PLA) between the lower density (<15 plants m −2 ) treatments and commonly used values (>20 plants m −2 ) at the growth habit but not genotype level. These differences in node addition and leaf development dynamics translated to marked differences among growth habits and densities in estimated leaf area indices and, consequently, in the estimated fraction of intercepted light at lower densities. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.01.0056 VL - 56 IS - 5 SP - 2713-2721 SN - 1435-0653 ER - TY - JOUR TI - Quantifying Leaf Area Development Parameters for Cowpea [Vigna unguiculata (L.) Walpers] AU - Hissene, Halime Mahamat AU - Vadez, Vincent AU - Michelangeli, Jose Clavijo AU - Halilou, Oumarou AU - Ndoye, Ibrahima AU - Soltani, Afshin AU - Sinclair, Thomas T2 - CROP SCIENCE AB - Cowpea [ Vigna unguiculata (L.) Walpers] is a major crop legume for the Sahelian zone in Africa. An accurate simulation of the growth and yield for cowpea that considers the environment would be a robust tool for evaluating improved management and plant genetics. The objective of this study was to parameterize a simple model framework to describe cowpea leaf area development. To obtain field data in divergent environments, leaf area development was measured for four genotypes at two sites: Patancheru, India, and Bambey, Senegal. In addition, the effect of plant density was tested at Patancheru. Leaf area development was considered in two steps: the increase in main stem node number as a function of temperature (i.e., phyllochron) and plant leaf area as a function of main stem node number. The difference in phyllochron values among genotypes was not significant at Bambey, but one genotype at Patancheru significantly diverged from the others. Also, there was a plant density effect at Patancheru, especially for genotype Suvita‐2. An allometric power function, used to calculate plant leaf area based on the number of nodes, required two parameters: PLAPOW, the exponent in the function, and PLACON, the linear multiplier of the equation. Determination of the two parameters at Patancheru showed a genotype effect in both site and plant‐density effect. To examine the practical impact of genotypic differences and density effects in light interception and shading, estimated leaf development parameters were used to calculate light interception. There was very little variation in light interception resulting from the observed range in leaf phyllochron, PLAPOW, and PLACON and in density responses among the cowpea genotypes. The results of these experiments showed that, in most cases, a single set of parameters can be used to describe light interception by cowpea leaf canopies. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.02.0132 VL - 56 IS - 6 SP - 3209-3217 SN - 1435-0653 ER - TY - JOUR TI - Persistence in and Release of 2,4-D and Azoxystrobin from Turfgrass Clippings AU - Jeffries, Matthew D. AU - Yelverton, Fred H. AU - Ahmed, Khalied A. AU - Gannon, Travis W. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Research has shown that pesticide residue in clippings from previously treated turfgrass may become bioavailable as grass decomposes, adversely affecting off‐target organisms. We conducted a field study to quantify 2,4‐D (2,4‐dichlorophenoxyacetic acid) and azoxystrobin (methyl(E)‐2‐{2[6‐(2‐cyanophenoxy)pyrmidin‐4‐yloxy]phenyl}‐3‐methoxyacrylate) residues in turfgrass clippings collected from hybrid bermudagrass [ Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt–Davy], tall fescue [ Lolium arundinaceum (Schreb.) S.J. Darbyshire], and zoysiagrass ( Zoysia japonica Steud.). A subsequent greenhouse experiment was conducted to measure pesticide release from clippings into water. 2,4‐D (1.6 kg a.i. ha −1 ) and azoxystrobin (0.6 kg a.i. ha −1 ) were applied to field plots at 32, 16, 8, 4, 2, 1, or 0 d before collection of the clippings. Clippings were collected from each experimental unit to quantify pesticide release from clippings into water. Both 2,4‐D and azoxystrobin were detected when turfgrass was treated over the 32‐d experimental period, suggesting that clipping management should be implemented for an extended period of time after application. Pesticide residue was detected in all water samples collected, confirming 2,4‐D and azoxystrobin release from turfgrass clippings; however, pesticide release varied between compounds. Two days after clippings were incorporated in water, 39 and 10% of 2,4‐D and azoxystrobin were released from clippings, respectively. Our research supports the currently recommended practice of returning clippings to the turfgrass stand when mowing because removal of 2,4‐D and azoxystrobin in clippings may reduce pest control and cause adverse off‐target impacts. Core Ideas 2,4‐D and azoxystrobin residues were detected in clippings 32 d after treatment. 2,4‐D and azoxystrobin were released from turfgrass clippings into water. Pesticide release from turfgrass clippings into water varied between compounds. DA - 2016/// PY - 2016/// DO - 10.2134/jeq2016.03.0081 VL - 45 IS - 6 SP - 2030-2037 SN - 1537-2537 ER - TY - JOUR TI - Mapping of Fusarium Head Blight Resistance Quantitative Trait Loci in Winter Wheat Cultivar NC-Neuse AU - Petersen, Stine AU - Lyerly, Jeanette H. AU - Maloney, Peter V. AU - Brown-Guedira, Gina AU - Cowger, Christina AU - Costa, Jose M. AU - Dong, Yanhong AU - Murphy, J. Paul T2 - CROP SCIENCE AB - Fusarium head blight (FHB), primarily caused by Fusarium graminearum , can significantly reduce the grain quality of wheat ( Triticum aestivum L.) due to mycotoxin contamination. The objective of this study was to identify quantitative trait loci (QTL) for FHB resistance in the moderately resistant soft red winter wheat cultivar NC‐Neuse. A total of 170 recombinant inbred lines (RILs) from a cross between NC‐Neuse and the susceptible cultivar AGS 2000 were evaluated in inoculated, mist‐irrigated field nurseries. The lines were evaluated for FHB incidence (INC), severity (SEV), Fusarium ‐damaged kernels (FDK), and deoxynivalenol (DON) content in seven environments between 2011 and 2014. A 3,419 cM linkage map was developed based on 1839 simple sequence repeat (SSR), diversity array technology (DArT), and single nucleotide polymorphism (SNP) markers. Seven FHB resistance QTL on chromosomes 1A, 1B, 1D, 2A, 4A, 5B, and 6A were mapped. The QTL alleles conferring resistance on 1A, 1B, 2A, 4A, and 6A originated from NC‐Neuse, while the alleles associated with resistance on 1D and 5B originated from AGS 2000. Quantitative trait loci effects ranged from 9 to 12% for INC, from 6 to 11% for SEV, from 8 to 20% for FDK, and from 6 to 18% for DON. The QTL on 5B co‐localized with the Vrn‐B1 locus. Kompetitive Allele‐Specific PCR (KASP) assays were developed for each NC‐Neuse QTL region. A preliminary test using these assays on recent Uniform Southern Winter Wheat Nursery (USWWN) entries indicated Qfhb.nc‐1A, Qfhb.nc‐1B, and Qfhb.nc‐6A as likely the best candidates for use in marker‐assisted selection. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.05.0312 VL - 56 IS - 4 SP - 1473-1483 SN - 1435-0653 ER - TY - JOUR TI - Irrigation Scheduling Using Predawn Leaf Water Potential Improves Water Productivity in Drip-Irrigated Cotton AU - Chastain, Daryl R. AU - Snider, John L. AU - Collins, Guy D. AU - Perry, Calvin D. AU - Whitaker, Jared AU - Byrd, Seth A. AU - Oosterhuis, Derrick M. AU - Porter, Wesley M. T2 - CROP SCIENCE AB - To address the effectiveness of predawn leaf water potential in plant‐based irrigation scheduling, Gossypium hirsutum L. plants were grown under fully irrigated and dryland conditions and under three predawn water potential (Ψ PD ) thresholds (−0.5, −0.7, and −0.9 MPa). Measurements included Ψ PD , plant height, mainstem node number, lint yield, water productivity, and continuous crop canopy temperature. We found that Ψ PD produced similar yields to current practices, while decreasing overall water use from 7 to 31%, depending on rainfall levels and the treatment utilized. When considered across both years of the study (2013 and 2014), using a −0.5‐MPa Ψ PD irrigation threshold consistently resulted in less irrigation applied than the checkbook method and maximum water productivity and lint yield. Using a well‐watered baseline developed in 2013 for canopy temperature versus vapor pressure deficit, we calculated a crop water stress index (CWSI) that exhibited a very strong, nonlinear relationship with season average Ψ PD values between approximately −0.4 and −0.7 MPa ( r 2 = 0.81). A strong, nonlinear relationship was also seen between CWSI and lint yield ( r 2 = 0.81). Predawn water potential appears to be an effective means of determining the need for irrigation in cotton, and in the current study, yield and water productivity were maximized at a season‐long average Ψ PD threshold of −0.5 MPa. Furthermore, when calibrated using Ψ PD –based irrigation triggers, canopy‐temperature derived CWSI appears to be a promising tool for future automated plant‐based irrigation scheduling in the southeastern United States. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.01.0009 VL - 56 IS - 6 SP - 3185-3195 SN - 1435-0653 ER - TY - JOUR TI - Increasing Soluble Phosphate Species by Treatment of Phosphate Rocks with Acidic Waste AU - Santos, Wedisson O. AU - Hesterberg, Dean AU - Mattiello, Edson M. AU - Vergutz, Leonardus AU - Barreto, Matheus S. C. AU - Silva, Ivo R. AU - Souza Filho, Luiz F. S. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - The development of efficient fertilizers with a diminished environmental footprint will help meet the increasing demand for food and nutrients by a growing global population. Our objective was to evaluate whether an acidic mine waste (AMW) could be used beneficially by reacting it with sparingly soluble phosphate rocks (PRs) to produce more soluble P fertilizer materials. Three PRs from Brazil and Peru were reacted with different concentrations of AMW. Changes in mineralogy and P species were determined using a combination of X‐ray diffraction and phosphorus K‐edge XANES spectroscopy, in addition to extractable P concentrations. Increasing the AMW concentration typically increased extractable P. X‐ray diffraction data showed transformation of apatite to other species when PRs were reacted with AMW at ≥50% (v/v) in water, with gypsum or anhydrite forming at AMW concentrations as low as 12.5%. Linear combination fitting analysis of X‐ray absorption near edge structure spectra also indicated a progressive transformation of apatite to noncrystalline Fe(III)‐phosphate and more soluble Ca‐phosphates with increasing AMW concentration. Because this AMW is costly to dispose of, reacting it with PR to produce a higher‐grade phosphate fertilizer material could decrease the environmental impacts of the AMW and diminish the consumption of pure acids in conventional P fertilizer production. Core Ideas Reusing fertilizer production waste can lower its environmental impact and enhance crop production. We evaluated products of acid mining waste reacted with phosphate rocks. Chemical speciation analyses indicated conversion of apatite to more soluble phosphates. New P products have agronomic potential. Plant growth tests are needed to measure these P products’ performance as fertilizers. DA - 2016/// PY - 2016/// DO - 10.2134/jeq2016.03.0079 VL - 45 IS - 6 SP - 1988-1997 SN - 1537-2537 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85003876062&partnerID=MN8TOARS ER - TY - JOUR TI - Heat Unit Accumulation and Days to Anthesis Relationship in Tobacco Genotypes with an Introgressed QTL Affecting Leaf Number AU - Wells, Randy AU - Eickholt, David P. J. AU - Lewis, Ramsey AU - Vann, Matthew C. AU - Fisher, Loren R. T2 - CROP SCIENCE AB - Plant breeders and crop managers would benefit from an increased ability to predict the requirements for onset of anthesis in tobacco ( Nicotiana tabacum L.). This study was performed to determine the relationship in the field between heat unit (HU) accumulation and the onset of anthesis in tobacco genotypes varying for the zygosity of an introgressed quantitative trait loci (QTL) designated as Many Leaves ( Ml ) affecting flowering team and leaf number. Three commercially important cultivars or breeding lines (Speight 168, K326, and NCTG‐61), their nearly isogenic homozygous ( MlMl ) and heterozygous ( Mlml ) counterparts, and three BC6F3 null‐segregant ( mlml ) lines, were evaluated at three locations and over 2 yr. Days to anthesis (DTA) and HU accumulation were determined. In each environment, the MlMl , Mlml , and mlml genotypes were found to be grouped according to the zygosity of the Ml trait, with the mlml genotypes flowering first followed by Mlml and MlMl genotypes, respectively. An exception to this trend was Speight 168 MlMl, which consistently fell within the Mlml grouping for DTA. No consistent relationships were observed between HU and DTA, which was highly variable among environments. Integrated HU (area under the HU curve) during the 28 d after transplanting (DAT) was positively associated ( R 2 = 0.98; P = 0.0001) with the range of DTA among all genotypes. Integrated HU was a better indicator of the pattern of HU attainment than merely the amount. Early HU exposure seemed important in determining the range in DTA amongst the genotypes examined. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.04.0278 VL - 56 IS - 6 SP - 3228-3236 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84990194504&partnerID=MN8TOARS ER - TY - JOUR TI - Evaluation of foliar applications of strobilurin fungicides in cotton across the Southern United States AU - Woodward, J. E. AU - Dodds, D. M. AU - Main, C. L. AU - Barber, L. T. AU - Boman, R. K. AU - Whitaker, J. R. AU - Edmisten, K. L. AU - Banks, J. C. AU - Buehring, N. W. AU - Allen, T. W. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 2 SP - 116-124 ER - TY - JOUR TI - Effectiveness of Livestock Exclusion in a Pasture of Central North Carolina AU - Line, Daniel E. AU - Osmond, Deanna L. AU - Childres, Wesley T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Reducing the export of nitrogen (N), phosphorus (P), and sediment from agricultural land in water‐supply watersheds is a continuing goal in central North Carolina. The objective of this project was to document the effectiveness of a combination of livestock exclusion fencing and nutrient management implemented on a beef cattle pasture located in the Piedmont region of North Carolina. The quantity and quality of discharge from two predominantly pasture watersheds were monitored simultaneously for 3.8 yr before and after implementation of the exclusion fencing and nutrient management in the treatment watershed; a control watershed remained unchanged. The excluded stream corridor was intentionally minimized by constructing the fence line about 3 m from the top of the streambank on either side and limiting it to the main stream channel only. Monitoring included collecting flow‐proportional samples during storm events and analyzing them for total Kjeldahl N (TKN), ammonia (NH 3 –N), and inorganic (NO x –N) N as well as total P (TP) and total suspended solids (TSS). Statistically significant reductions were observed in TKN (34%), NH 3 –N (54%), TP (47%), and TSS (60%) loads in the treatment relative to the control watershed after fencing, whereas storm discharge and NO x –N loads were not significantly different. These data show that even a relatively narrow exclusion corridor implemented on only the main stream channel can significantly reduce the export of N, P, and sediment from a beef cattle pasture. Core Ideas Document, through water quality monitoring, the effectiveness of livestock exclusion fencing Livestock exclusion reduced nitrogen, phosphorus, and sediment export from a pasture. Statistical analysis is required to assess trends in water quality monitoring data. DA - 2016/// PY - 2016/// DO - 10.2134/jeq2016.03.0089 VL - 45 IS - 6 SP - 1926-1932 SN - 1537-2537 ER - TY - JOUR TI - Athletic Field Paint Color Impacts Transpiration and Canopy Temperature in Bermudagrass AU - Reynolds, William Casey AU - Miller, Grady L. AU - Livingston, David P. AU - Rufty, Thomas W. T2 - Crop Science AB - Athletic field paints have varying impacts on turfgrass health that have been linked to their ability to alter photosynthetically active radiation and photosynthesis on the basis of color. It was further hypothesized they may also alter transpiration and canopy temperature by disrupting gas exchange at the leaf surface. Growth chamber experiments evaluated the effects of air temperature and six colors of paint on daily water loss and canopy temperature in ‘Tifway’ bermudagrass [ Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt‐Davy]. Daily water loss and canopy temperature were measured every 24 h using gravimetric techniques and an infrared digital thermometer, while lab experiments examined the thickness of white and black paint on the leaf surface. In nonpainted bermudagrass canopies, daily water loss increased ( P ≤ 0.0001) with canopy temperature from 29 to 36°C, while in painted bermudagrass canopies it decreased ( P ≤ 0.0001) as canopy temperature increased from 29 to 40°C. Yellow and white paint impacted transpiration and canopy temperature the least, while black and blue caused the greatest reductions in transpiration and highest increases in canopy temperature. Cross‐sections of painted Tifway indicate that paint may limit evaporative cooling by clogging stomata. Increased absorption of radiant energy by paint coupled with limited evaporative cooling result in increased heat stress and decreased turfgrass performance in painted canopies. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2016.01.0028 VL - 56 IS - 4 SP - 2016 LA - en OP - SN - 0011-183X UR - http://dx.doi.org/10.2135/cropsci2016.01.0028 DB - Crossref ER - TY - JOUR TI - A universal assay for the detection of siderophore activity in natural waters AU - Andrews, Megan Y. AU - Duckworth, Owen T2 - BIOMETALS DA - 2016/12// PY - 2016/12// DO - 10.1007/s10534-016-9979-4 VL - 29 IS - 6 SP - 1085-1095 SN - 1572-8773 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84994285887&partnerID=MN8TOARS KW - Siderophores KW - Environmental assay KW - Metal uptake KW - Biogeochemistry ER - TY - JOUR TI - Soil Weathering as an Engine for Manganese Contamination of Well Water AU - Gillispie, Elizabeth C. AU - Austin, Robert E. AU - Rivera, Nelson A. AU - Bolich, Rick AU - Duckworth, Owen W. AU - Bradley, Phil AU - Amoozegar, Aziz AU - Hesterberg, Dean AU - Polizzotto, Matthew L. T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Manganese (Mn) contamination of well water is recognized as an environmental health concern. In the southeastern Piedmont region of the United States, well water Mn concentrations can be >2 orders of magnitude above health limits, but the specific sources and causes of elevated Mn in groundwater are generally unknown. Here, using field, laboratory, spectroscopic, and geospatial analyses, we propose that natural pedogenetic and hydrogeochemical processes couple to export Mn from the near-surface to fractured-bedrock aquifers within the Piedmont. Dissolved Mn concentrations are greatest just below the water table and decrease with depth. Solid-phase concentration, chemical extraction, and X-ray absorption spectroscopy data show that secondary Mn oxides accumulate near the water table within the chemically weathering saprolite, whereas less-reactive, primary Mn-bearing minerals dominate Mn speciation within the physically weathered transition zone and bedrock. Mass-balance calculations indicate soil weathering has depleted over 40% of the original solid-phase Mn from the near-surface, and hydrologic gradients provide a driving force for downward delivery of Mn. Overall, we estimate that >1 million people in the southeastern Piedmont consume well water containing Mn at concentrations exceeding recommended standards, and collectively, these results suggest that integrated soil-bedrock-system analyses are needed to predict and manage Mn in drinking-water wells. DA - 2016/9/20/ PY - 2016/9/20/ DO - 10.1021/acs.est.6b01686 VL - 50 IS - 18 SP - 9963-9971 SN - 1520-5851 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84988464669&partnerID=MN8TOARS ER - TY - JOUR TI - Soil Organic Matter Content and Volumetric Water Content Affect Indaziflam-Soil Bioavailability AU - Jeffries, Matthew D. AU - Gannon, Travis W. T2 - WEED SCIENCE AB - Indaziflam is a cellulose biosynthesis-inhibiting herbicide for annual weed control in various agricultural systems. Sporadic cases of unacceptable injury to desirable plants have been reported after indaziflam application, which may have been due to conditions favoring increased indaziflam–soil bioavailability. Research was conducted from 2013 to 2015 on a sandy soil to elucidate the effects of soil organic matter content (SOMC) and soil volumetric water content (SVWC) on indaziflam–soil bioavailability. Indaziflam was applied (50 or 100 g ha –1 ) at fall only, fall plus spring, and spring only timings to plots in a factorial arrangement of SOMC, pre–indaziflam application (PrIA) SVWC, and post–indaziflam application (PoIA) SVWC. After application, field soil cores were collected for a subsequent greenhouse bioassay experiment, where foliage mass reduction of perennial ryegrass seeded from 0 to 15 cm soil depth was used as an indicator of indaziflam–soil bioavailability throughout the profile. Significant edaphic effects were observed at 0 to 2.5, 2.5 to 5, and 5 to 7.5 cm depths, with increased bioavailability at low compared with high SOMC. Pre–indaziflam application SVWC did not affect bioavailability, whereas PoIA high SVWC increased indaziflam–soil bioavailability at 2.5 to 7.5 cm depth compared with PoIA low SVWC. Low SOMC–PoIA high SVWC decreased perennial ryegrass foliage mass 40 and 37% at 5 to 7.5 cm depth from cores collected 10 and 14 wk after treatment, respectively, whereas reductions from all other SOMC–PoIA SVWC combinations were < 12% and did not vary from each other. Pearson's correlation coefficients showed a moderate, positive relationship between perennial ryegrass mass reductions at 0 to 2.5, 2.5 to 5, 0 to 5, and 0 to 10 cm depths and hybrid bermudagrass cover reduction, which suggests conditions favoring increased indaziflam–soil bioavailability can adversely affect plant growth. Data from this research will aid land managers to use indaziflam effectively without adversely affecting growth of desirable species. DA - 2016/// PY - 2016/// DO - 10.1614/ws-d-16-00039.1 VL - 64 IS - 4 SP - 757-765 SN - 1550-2759 KW - Application timing KW - bioassay KW - cellulose biosynthesis inhibition KW - herbicide injury KW - herbicide leaching ER - TY - JOUR TI - Simple systems for treating pumped, turbid water with flocculants and a geotextile dewatering bag AU - Kang, Jihoon AU - McLaughlin, Richard A. T2 - JOURNAL OF ENVIRONMENTAL MANAGEMENT AB - Pumping sediment-laden water from excavations is often necessary on construction sites. This water is often treated by pumping it through geotextile dewatering bags. The bags are not designed to filter the fine sediments that create high turbidity, but dosing with a flocculant prior to the bag could result in greater turbidity control. This study compared two systems for introducing flocculant: passive dosing of commercial solid biopolymer (chitosan) and injection of dissolved polyacrylamide (PAM) in a length of corrugated pipe connected to the bag. The biopolymer system consisted of sequential porous socks containing a "charging agent" followed by chitosan in the corrugated pipe with two levels of dosing. The dissolved PAM was injected into turbid water at a flow-weighted concentration at 1 mg L(-1). For each treatment, sediment-laden turbid water in the range of 2000 to 3500 nephelometric turbidity units (NTU) was pumped into the upstream of corrugated pipe and samples were taken from pipe entrance, pipe exit, and dewatering bag exit. Without flocculant treatment, the dewatering bag reduced turbidity by 70% but the addition of flocculant increased the turbidity reduction up to 97% relative to influent. At the pipe exit, the low-dose biopolymer was less effective in reducing turbidity (37%) but it was equally effective as the high-dose biopolymer or PAM injection after the bag. Our results suggest that a relatively simple treatment with flocculants, either passively or actively, can be very effective in reducing turbidity for pumped water on construction sites. DA - 2016/11/1/ PY - 2016/11/1/ DO - 10.1016/j.jenvman.2016.07.071 VL - 182 SP - 208-213 SN - 1095-8630 KW - Biopolymer KW - Construction site KW - Geotextile dewatering bag KW - Polyacrylamide KW - Turbidity ER - TY - JOUR TI - Second edition WETLAND SOILS Genesis, Hydrology, Landscapes, and Classification Preface AU - Vepraskas, Michael AU - Craft, C. B. T2 - Wetland Soils: Genesis, Hydrology, Landscapes, and Classification, 2nd edition DA - 2016/// PY - 2016/// DO - 10.1201/b18996 SP - VII- ER - TY - JOUR TI - Redox chemistry of hydric soils AU - Vepraskas, M. J. AU - Polizzotto, M. AU - Faulkner, S. P. T2 - Wetland Soils: Genesis, Hydrology, Landscapes, and Classification, 2nd edition DA - 2016/// PY - 2016/// SP - 105-132 ER - TY - JOUR TI - Morphological features of hydric and reduced soils AU - Vepraskas, M. J. AU - Vaughan, K. L. T2 - Wetland Soils: Genesis, Hydrology, Landscapes, and Classification, 2nd edition DA - 2016/// PY - 2016/// SP - 189-217 ER - TY - JOUR TI - Hydric soils and wetlands in riverine systems AU - Drohan, P. J. AU - Lindbo, D. L. AU - Richardson, J. L. T2 - Wetland Soils: Genesis, Hydrology, Landscapes, and Classification, 2nd edition DA - 2016/// PY - 2016/// SP - 325-345 ER - TY - JOUR TI - History of the concept of hydric soil AU - Vepraskas, M. J. T2 - Wetland Soils: Genesis, Hydrology, Landscapes, and Classification, 2nd edition DA - 2016/// PY - 2016/// SP - 23-37 ER - TY - JOUR TI - Fungal biomineralization of montmorillonite and goethite to short-range-ordered minerals AU - Li, Huan AU - Hu, Shuijin AU - Polizzotto, Matthew L. AU - Chang, Xiaoli AU - Shen, Qirong AU - Ran, Wei AU - Yu, Guanghui T2 - GEOCHIMICA ET COSMOCHIMICA ACTA AB - Highly reactive nano-scale minerals, e.g., short-range-ordered minerals (SROs) and other nanoparticles, play an important role in soil carbon (C) retention. Yet, the mechanisms that govern biomineralization from bulk minerals to highly reactive nano-scale minerals remain largely unexplored, which critically hinders our efforts toward managing nano-scale minerals for soil C retention. Here we report the results from a study that explores structural changes during Aspergillus fumigatus Z5 transformation of montmorillonite and goethite to SROs. We examined the morphology and structure of nano-scale minerals, using high-resolution transmission electron microscopy, time-resolved solid-state 27Al and 29Si NMR, and Fe K-edge X-ray absorption fine structure spectroscopy combined with two dimensional correlation spectroscopy (2D COS) analysis. Our results showed that after a 48-h cultivation of montmorillonite and goethite with Z5, new biogenic intracellular and extracellular reactive nano-scale minerals with a size of 3–5 nm became abundant. Analysis of 2D COS further suggested that montmorillonite and goethite were the precursors of the dominant biogenic nano-scale minerals. Carbon 1s near edge X-ray absorption fine structure (NEXAFS) spectra and their deconvolution results demonstrated that during fungus Z5 growth, carboxylic C (288.4–289.1 eV) was the dominant organic group, accounting for approximately 34% and 59% in the medium and aggregates, respectively. This result suggested that high percentage of the production of organic acids during the growth of Z5 was the driving factor for structural changes during biomineralization. This is, to the best of our knowledge, the first report of the structural characterization of nano-scale minerals by 2D COS, highlighting its potential to elucidate biomineralization pathways and thus identify the precursors of nano-scale minerals. DA - 2016/10// PY - 2016/10// DO - 10.1016/j.gca.2016.07.009 VL - 191 SP - 17-31 SN - 1872-9533 KW - Biomineralization KW - Fungi KW - High-resolution transmission electron microscopy KW - Montmorillonite KW - Short-range-ordered minerals KW - Two dimensional correlation spectroscopy ER - TY - JOUR TI - Disentangling the influence of urbanization and invasion on endemic geckos in tropical biodiversity hot spots: A case study of Phyllodactylus martini (Squamata: Phyllodactylidae) along an Urban Gradient in Curacao AU - Dornburg, A. AU - Lippi, C. AU - Federman, S. AU - Moore, J. A. AU - Warren, D. L. AU - Iglesias, T. L. AU - Brandley, M. C. AU - Watkins-Colwell, G. J. AU - Lamb, A. D. AU - Jones, A. T2 - Bulletin of the Peabody Museum of Natural History AB - Predicting the response of endemic species to urbanization has emerged as a fundamental challenge in 21st century conservation biology. The factors that underlie population declines of reptiles are particularly nebulous, as these are often the least understood class of vertebrates in a given community. In this study, we assess correlations between feeding ecology and phenotypic traits of the Lesser Antillean endemic Dutch leaf-toed gecko, Phyllodactylus martini, along an urban gradient in the Caribbean island of Curaçao. There has been a marked decline of this species in developed habitats associated with the invasive tropical house gecko Hemidactylus mabouia. We find a correlation between aspects of locomotor morphology and prey in undeveloped habitats that is absent in developed habitats. Analyses of stomach contents further suggest that Phyllodactylus martini alters primary prey items in developed areas. However, changes in prey promote the overlap in foraging niches between Phyllodactylus martini and Hemidactylus mabouia, suggesting that direct resource competition is contributing to the decline of Phyllodactylus martini. In addition to competitive exclusion, we suggest that the urban extirpation of Phyllodactylus martini could also be attributed to a top-down control on population growth by Hemidactylus mabouia. Colonizations of walls put Phyllodactylus martini in direct contact with Hemidactylus mabouia increasing the chances for predation events, as evidenced by our observation of a predation event on a Phyllodactylus martini juvenile by an adult Hemidactylus mabuoia. In total, our results add to a growing body of literature demonstrating the threat that invasive synanthropic reptiles pose to endemics that might otherwise be able to cope with increased urbanization pressures. DA - 2016/// PY - 2016/// DO - 10.3374/014.057.0209 VL - 57 IS - 2 SP - 147-164 ER - TY - JOUR TI - Determination of coefficient defining leaf area development in different genotypes, plant types and planting densities in peanut (Arachis hypogeae L.) AU - Halilou, Oumarou AU - Hissene, Halime Mahamat AU - Michelangeli, Jose A. Clavijo AU - Hamidou, Falalou AU - Sinclair, Thomas R. AU - Soltani, Afshin AU - Mahamane, Saadou AU - Vadez, Vincent T2 - FIELD CROPS RESEARCH AB - Rapid leaf area development may be attractive under a number of cropping conditions to enhance the vigor of crop establishment and allow rapid canopy closure for maximizing light interception and shading of weed competitors. This study was undertaken to determine (1) if parameters describing leaf area development varied among ten peanut (Arachis hypogeae L.) genotypes grown in field and pot experiments, (2) if these parameters were affected by the planting density, and (3) if these parameters varied between Spanish and Virginia genotypes. Leaf area development was described by two steps: prediction of main stem number of nodes based on phyllochron development and plant leaf area dependent based on main stem node number. There was no genetic variation in the phyllochron measured in the field. However, the phyllochron was much longer for plants grown in pots as compared to the field-grown plants. These results indicated a negative aspect of growing peanut plants in the pots used in this experiment. In contrast to phyllochron, there was no difference in the relationship between plant leaf area and main stem node number between the pot and field experiments. However, there was genetic variation in both the pot and field experiments in the exponential coefficient (PLAPOW) of the power function used to describe leaf area development from node number. This genetic variation was confirmed in another experiment with a larger number of genotypes, although possible G × E interaction for the PLAPOW was found. Sowing density did not affect the power function relating leaf area to main stem node number. There was also no difference in the power function coefficient between Spanish and Virginia genotypes. SSM (Simple Simulation model) reliably predicted leaf canopy development in groundnut. Indeed the leaf area showed a close agreement between predicted and observed values up to 60000 cm2 m-2. The slightly higher prediction in India and slightly lower prediction in Niger reflected GxE interactions. Until more understanding is obtained on the possible GxE interaction effects on the canopy development, a generic PLAPOW value of 2.71, no correction for sowing density, and a phyllochron on 53 °C could be used to model canopy development in peanut. DA - 2016/12// PY - 2016/12// DO - 10.1016/j.fcr.2016.09.013 VL - 199 SP - 42-51 SN - 1872-6852 KW - Phyllochron KW - Leaf area KW - Peanut KW - Allometric model KW - Degree-days ER - TY - JOUR TI - Row spacing and seeding rate effects on canola population, weed competition and yield in winter organic canola production AU - Vann, R.A. AU - Reberg-Horton, S.C. AU - Brinton, C.M. T2 - Agronomy Journal AB - Increasing seeding rate and widening row spacing to allow for between row cultivation may reduce weed competition in organic canola ( Brassica napus L.) production. Research was conducted to evaluate the effects of row spacing and seeding rate on canola population, weed competition, and yield in organic canola production. Canola variety Hornet was planted at five seeding rates (3.4, 6.7, 10.1, 13.4, and 16.8 kg ha −1 ) at three row spacings (17, 34, 68 cm) in Goldsboro, Kinston, and Salisbury, NC, in 2011 and 2012. Between row cultivation was performed in the 68‐cm row spacing as weather permitted. Canola population increased with increasing seeding rate across all row spacings, and canola populations were highest with the 17‐cm row spacing, followed by the 34‐ then 68‐cm row spacings. Yield was similar across row spacings at the lower seeding rates in five of the six environments. At these environments, yield tended to increase in the 17‐cm row spacing as seeding rate increased but declined in the 68‐cm row spacing with increasing seeding rate. In one environment with a unique weed community, weed suppression and yield were higher with the 68‐cm row spacing. It was concluded that the yield plasticity of canola will provide producers flexibility in selecting row spacing, and seeding rate selections should be based on desired row spacing. Core Ideas Increasing canola seeding rate and widening row spacing to allow for between row cultivation may serve as mechanisms to reduce weed competition in canola production, but have rarely been evaluated in organic production. This study was conducted to evaluate seeding rate and row spacing effects on weed competition and yield in organic canola production. Despite different canola populations across canola row spacings, yield tended to be similar at low seeding rates across the row spacings indicating canola has the ability to compensate for low population. Depending on the weed species at your environment, widening row spacing to allow for between row cultivation may prove critical for reducing weed competition and increasing canola yield. Yield tended to increase with increases in seeding rate at the 17‐cm row spacing, however yield declines were observed with higher seeding rates in the 68‐cm row spacing, which is likely attributed to intraspecific competition. Organic canola producers have flexibility when selecting row spacing and seeding rates due to the great plasticity of canola. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2016.02.0097 VL - 108 IS - 6 SP - 2425–2432 SN - 1435-0645 ER - TY - JOUR TI - Productive and reproductive performance and metabolic profiles of ewes supplemented with hydroponically grown green wheat (Triticum aestivum L.) AU - Guerrero-Cervantes, M. AU - Cerrillo-Soto, M. A. AU - Plascencia, A. AU - Salem, A. Z. M. AU - Estrada-Angulo, A. AU - Rios-Rincon, F. G. AU - Luginbuhl, J. M. AU - Bernal-Barragan, H. AU - Abdalla, A. L. T2 - ANIMAL FEED SCIENCE AND TECHNOLOGY AB - Twenty six Katahdin ewes (i.e., female lambs from breeding to 2 mo of their 1st lactation) were used in a completely randomized design (13/treatment) to evaluate effects of replacement of dietary dry-rolled corn grain (DRC) and cottonseed meal (CSM) with hydroponically grown whole plant green wheat (HGW; Triticum aestivum L.) on productive parameters and blood metabolites during mating, gestation and lactation, and on body weight (BW) gain of their lambs in their 1st 60 days of age. The gestation diet contained 70% oat hay, 20% rolled corn grain and 10% cottonseed meal, while the lactation diet contained 50% oat hay, 20% DRC and 30% CSM. Treatments consisted of total replacement of DRC and CSM with HGW in the gestation diet, while in the lactation diet HGW replaced 100% of the DRC and 33% of the CSM. There were no diet effects on reproductive parameters, and substitution of DRC and CSM with HGW did not affect dry matter intake during gestation and lactation. The BW gain of the lambs that were fed HGW did not differ from controls in the first 2 months of gestation, while it was lower (P < 0.05) at the last 3 months of gestation. Feeding HGW did not affect birth BW of lambs or subsequent BW gains through 60 days of age. Plasma non-esterified fatty acids (NEFA) were not affected by the diets fed during gestation, but were 56% lower (P < 0.05) at day 60 of lactation. Plasma glucose was only lower (P < 0.05) at day 90 of gestation, and blood urea nitrogen was only lower (P < 0.05) at day 30 of lactation. There were no effects of diets on plasma insulin, cortisol or progesterone during gestation and lactation. Hydroponically grown green wheat is a suitable substitute for a portion of the DRC and CSM in ewes diets during gestation and lactation without negative effects. DA - 2016/11// PY - 2016/11// DO - 10.1016/j.anifeedsci.2016.09.003 VL - 221 SP - 206-214 SN - 1873-2216 KW - Plasma metabolites KW - Female lambs KW - Hydroponic wheat KW - Metabolic hormones KW - Reproductive performance ER - TY - JOUR TI - Production and soil responses to intercropping of forage grasses with corn and soybean silage AU - Pariz, C. M. AU - Costa, C. AU - Crusciol, C. A. C. AU - Meirelles, P. R. L. AU - Castilhos, A. M. AU - Andreotti, M. AU - Costa, N. R. AU - Martello, J. M. AU - Souza, D. M. AU - Sarto, J. R. W. AU - Franzluebbers, A. J. T2 - Agronomy Journal AB - Agricultural management systems are needed to simultaneously enhance production, and improve soil quality. We investigated the effects of intercropped grass on production of corn ( Zea mays L.) harvested for silage at 0.20 and 0.45 m height in the summer, as well as on production of subsequent forage, silage soybean [ Glycine max (L.) Merr.], and soil responses on a Typic Haplorthox in Botucatu, SP, Brazil. Palisade grass [ Urochloa brizantha (Hochst. ex A. Rich.) R. Webster ‘Marandu’] was the introduced companion crop with corn (Years 1 and 2), while signal grass [ Urochloa decumbens (Stapf) R. Webster ‘Basilisk’] was the residual weedy species in comparison. Guinea grass [ Urochloa maxima (Jacq.) R. Webster ‘Aruãna’] was the introduced companion crop with soybean (Year 3), with only a residual effect of crop systems from the previous 2 yr. When cut at 0.45 m compared with 0.20 m height, corn intercropped with palisade grass had greater leaf nutrient concentrations, agronomic characteristics, forage mass of pasture for grazing by lambs ( Ovis aries ), greater surface mulch produced, and greater quantity of N, P, and K returned to soil. Greater soil organic matter, P, K, and Mg concentration, and base saturation in the surface soil depth and lower soil penetration resistance at all depths occurred at 0.45 m than at 0.20 m corn silage cutting height intercropped with palisade grass. Analyzing the system as a whole, harvesting corn silage crop with palisade grass intercrop at 0.45 m height was the most viable option in this integrated crop–livestock system (ICLS). Core Ideas Agricultural management systems are needed to enhance production and improve soil quality. After corn silage harvest, pasture was grazed by lambs in winter/spring using a semi‐feedlot system. Harvesting corn silage crop with palisade grass intercrop at 0.45 m height was the most viable option. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2016.02.0082 VL - 108 IS - 6 SP - 2541-2553 ER - TY - JOUR TI - Persistent Supercooling of Reproductive Shoots Is Enabled by Structural Ice Barriers Being Active Despite an Intact Xylem Connection AU - Kuprian, Edith AU - Tuong, Tan D. AU - Pfaller, Kristian AU - Wagner, Johanna AU - Livingston, David P., III AU - Neuner, Gilbert T2 - PLOS ONE AB - Extracellular ice nucleation usually occurs at mild subzero temperatures in most plants. For persistent supercooling of certain plant parts ice barriers are necessary to prevent the entry of ice from already frozen tissues. The reproductive shoot of Calluna vulgaris is able to supercool down to below -22°C throughout all developmental stages (shoot elongation, flowering, fruiting) despite an established xylem conductivity. After localization of the persistent ice barrier between the reproductive and vegetative shoot at the base of the pedicel by infrared differential thermal analysis, the currently unknown structural features of the ice barrier tissue were anatomically analyzed on cross and longitudinal sections. The ice barrier tissue was recognized as a 250 μm long constriction zone at the base of the pedicel that lacked pith tissue and intercellular spaces. Most cell walls in this region were thickened and contained hydrophobic substances (lignin, suberin, and cutin). A few cell walls had what appeared to be thicker cellulose inclusions. In the ice barrier tissue, the area of the xylem was as much as 5.7 times smaller than in vegetative shoots and consisted of tracheids only. The mean number of conducting units in the xylem per cross section was reduced to 3.5% of that in vegetative shoots. Diameter of conducting units and tracheid length were 70% and 60% (respectively) of that in vegetative shoots. From vegetative shoots water transport into the ice barrier must pass pit membranes that are likely impermeable to ice. Pit apertures were about 1.9 μm x 0.7 μm, which was significantly smaller than in the vegetative shoot. The peculiar anatomical features of the xylem at the base of the pedicel suggest that the diameter of pores in pit membranes could be the critical constriction for ice propagation into the persistently supercooled reproductive shoots of C. vulgaris. DA - 2016/9/15/ PY - 2016/9/15/ DO - 10.1371/journal.pone.0163160 VL - 11 IS - 9 SP - SN - 1932-6203 ER - TY - JOUR TI - Genetic Architecture of Domestication-Related Traits in Maize AU - Xue, Shang AU - Bradbury, Peter J. AU - Casstevens, Terry AU - Holland, James B. T2 - GENETICS AB - Strong directional selection occurred during the domestication of maize from its wild ancestor teosinte, reducing its genetic diversity, particularly at genes controlling domestication-related traits. Nevertheless, variability for some domestication-related traits is maintained in maize. The genetic basis of this could be sequence variation at the same key genes controlling maize-teosinte differentiation (due to lack of fixation or arising as new mutations after domestication), distinct loci with large effects, or polygenic background variation. Previous studies permit annotation of maize genome regions associated with the major differences between maize and teosinte or that exhibit population genetic signals of selection during either domestication or postdomestication improvement. Genome-wide association studies and genetic variance partitioning analyses were performed in two diverse maize inbred line panels to compare the phenotypic effects and variances of sequence polymorphisms in regions involved in domestication and improvement to the rest of the genome. Additive polygenic models explained most of the genotypic variation for domestication-related traits; no large-effect loci were detected for any trait. Most trait variance was associated with background genomic regions lacking previous evidence for involvement in domestication. Improvement sweep regions were associated with more trait variation than expected based on the proportion of the genome they represent. Selection during domestication eliminated large-effect genetic variants that would revert maize toward a teosinte type. Small-effect polygenic variants (enriched in the improvement sweep regions of the genome) are responsible for most of the standing variation for domestication-related traits in maize. DA - 2016/9// PY - 2016/9// DO - 10.1534/genetics.116.191106 VL - 204 IS - 1 SP - 99-+ SN - 1943-2631 UR - https://doi.org/10.1534/genetics.116.191106 KW - quantitative trait loci KW - nested association mapping KW - genome-wide association study KW - variance components KW - Zea mays ER - TY - JOUR TI - Effects of tillage and compost amendment on infiltration in compacted soils AU - Mohammadshirazi, F. AU - Brown, V. K. AU - Heitman, J. L. AU - McLaughlin, R. A. T2 - JOURNAL OF SOIL AND WATER CONSERVATION AB - Soils are compacted during land development through soil excavation and heavy equipment traffic. Compacted soils have limited infiltration and are susceptible to erosion. Infiltration can be enhanced by various approaches including tillage and compost addition. The objective of this study was to determine the efficacy of tillage and adding compost to reduce stormwater runoff and sediment loss by improving infiltration in simulated postconstruction soils. Tillage treatments were tested at two sites in the Piedmont region of North Carolina (Piedmont 1 and 2). Prior to applying tillage and amendment, soils at both sites were graded to remove the surface horizon and compacted with a vibratory roller. At Piedmont 1, the treatments were compacted with no tillage, shallow (15 cm [5.9 in] depth) tillage (ST), and deep (30 cm [11.8 in] depth) tillage (DT). At Piedmont 2 the treatments were compacted, DT, and DT with incorporated compost (DT+Com). The grass seed mixtures recommended by the North Carolina Department of Transportation for the location (Piedmont) and time of planting were applied at each site. Runoff volumes (RV) and total suspended solids were measured after each of the first 12 and 13 storm events at Piedmont 1 and 2, respectively. Infiltration rate (IR) and bulk density (BD) were determined five and seven months after establishment at Piedmont 1 and 2, respectively. At both sites, RV and total amount of soil loss were reduced with tillage by 60% to 82% during the monitoring period. Neither deeper tillage nor incorporating compost significantly affected these results. Grass establishment was significantly better with tillage. The IRs measured at the end of the monitoring period were around 1 cm h−1 (0.4 in hr−1) in the compacted treatment but ranged from 19 to 33 cm h−1 (7.5 to 13 in hr−1) in the tilled treatments, again with no effects of tillage depth or compost. The results suggest that tillage to a depth of at least 15 cm (6 in) can be highly effective for improving soil conditions and reducing runoff and erosion from soils compacted as the result of construction activities. DA - 2016/// PY - 2016/// DO - 10.2489/jswc.71.6.443 VL - 71 IS - 6 SP - 443-449 SN - 1941-3300 KW - compost KW - construction site KW - erosion KW - runoff KW - tillage ER - TY - JOUR TI - Effects of Cover Crops, Compost, and Vermicompost on Strawberry Yields and Nitrogen Availability in North Carolina AU - Beck, John E. AU - Schroeder-Moreno, Michelle S. AU - Fernandez, Gina E. AU - Grossman, Julie M. AU - Creamer, Nancy G. T2 - HORTTECHNOLOGY AB - Summer cover crop rotations, compost, and vermicompost additions can be important strategies for transition to organic production that can provide various benefits to crop yields, nitrogen (N) availability, and overall soil health, yet are underused in strawberry ( Fragaria × ananassa ) production in North Carolina. This study was aimed at evaluating six summer cover crop treatments including pearl millet ( Pennisetum glaucum ), soybean ( Glycine max ), cowpea ( Vigna unguiculata ), pearl millet/soybean combination, pearl millet/cowpea combination, and a no cover crop control, with and without vermicompost additions for their effects on strawberry growth, yields, nutrient uptake, weeds, and soil inorganic nitrate-nitrogen and ammonium-nitrogen in a 2-year field experiment. Compost was additionally applied before seeding cover crops and preplant N fertilizer was reduced by 67% to account for organic N additions. Although all cover crops (with compost) increased soil N levels during strawberry growth compared with the no cover crop treatment, cover crops did not impact strawberry yields in the first year of the study. In the 2nd year, pearl millet cover crop treatments reduced total and marketable strawberry yields, and soybean treatments reduced marketable strawberry yields when compared with the no cover crop treatment, whereas vermicompost additions increased strawberry biomass and yields. Results from this study suggest that vermicompost additions can be important sustainable soil management strategies for transitional and certified organic strawberry production. Summer cover crops integrated with composts can provide considerable soil N, reducing fertilizer needs, but have variable responses on strawberry depending on the specific cover crop species or combination. Moreover, these practices are suitable for both organic and conventional strawberry growers and will benefit from longer-term studies that assess these practices individually and in combination and other benefits in addition to yields. DA - 2016/10// PY - 2016/10// DO - 10.21273/horttech03447-16 VL - 26 IS - 5 SP - 604-613 SN - 1943-7714 KW - Fragaria Xananassa KW - sustainable agriculture KW - crop rotation KW - methyl bromide alternative KW - organic transition practices KW - nutrient management ER - TY - JOUR TI - Combining ability for winter survival and turf quality traits in st. augustinegrass AU - Kimball, J. A. AU - Isleib, T. G. AU - Reynolds, W. C. AU - Zuleta, M. C. AU - Milla-Lewis, S. R. T2 - HortScience DA - 2016/// PY - 2016/// VL - 51 IS - 7 SP - 810-815 ER - TY - JOUR TI - The Seed Biotinylated Protein of Soybean (Glycine max): A Boiling-Resistant New Allergen (Gly m 7) with the Capacity To Induce IgE-Mediated Allergic Responses AU - Riascos, John J. AU - Weissinger, Sandra M. AU - Weissinger, Arthur K. AU - Kulis, Michael AU - Burks, A. Wesley AU - Pons, Laurent T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - Soybean is a common allergenic food; thus, a comprehensive characterization of all the proteins that cause allergy is crucial to the development of effective diagnostic and immunotherapeutic strategies. A cDNA library was constructed from seven stages of developing soybean seeds to investigate candidate allergens. We searched the library for cDNAs encoding a seed-specific biotinylated protein (SBP) based on its allergenicity in boiled lentils. A full-length cDNA clone was retrieved and expressed as a 75.6-kDa His-tagged recombinant protein (rSBP) in Escherichia coli. Western immunoblotting of boiled bacterial extracts demonstrated specific IgE binding to rSBP, which was further purified by metal affinity and anion exchange chromatographies. Of the 23 allergic sera screened by ELISA, 12 contained IgEs specific to the purified rSBP. Circular dichroism spectroscopy revealed a predominantly unordered structure consistent with SBP’s heat stability. The natural homologues (nSBP) were the main proteins isolated from soybean and peanut embryos after streptavidin affinity purification, yet they remained low-abundance proteins in the seed as confirmed by LC-MS/MS. Using capture ELISAs, the soybean and peanut nSBPs were bound by IgEs in 78 and 87% of the allergic sera tested. The soybean nSBP was purified to homogeneity and treatments with different denaturing agents before immunoblotting highlighted the diversity of its IgE epitopes. In vitro activation of basophils was assessed by flow cytometry in a cohort of peanut-allergic children sensitized to soybean. Stronger and more frequent (38%) activations were induced by nSBP-soy compared to the major soybean allergen, Gly m 5. SBPs may represent a novel class of biologically active legume allergens with the structural resilience to withstand many food-manufacturing processes. DA - 2016/5/18/ PY - 2016/5/18/ DO - 10.1021/acs.jafc.5b05873 VL - 64 IS - 19 SP - 3890-3900 SN - 1520-5118 KW - Glycine max KW - Arachis hypogaea KW - biotin KW - allergenic orthologues ER - TY - JOUR TI - Phenotypic variation and identification of quantitative trait loci for ozone tolerance in a Fiskeby III x Mandarin (Ottawa) soybean population AU - Burton, Amy L. AU - Burkey, Kent O. AU - Carter, Thomas E., Jr. AU - Orf, James AU - Cregan, Perry B. T2 - THEORETICAL AND APPLIED GENETICS DA - 2016/6// PY - 2016/6// DO - 10.1007/s00122-016-2687-1 VL - 129 IS - 6 SP - 1113-1125 SN - 1432-2242 ER - TY - JOUR TI - Histology Atlas of the Developing Mouse Hepatobiliary Hemolymphatic Vascular System with Emphasis on Embryonic Days 11.5-18.5 and Early Postnatal Development AU - Swartley, Olivia M. AU - Foley, Julie F. AU - Livingston, David P., III AU - Cullen, John M. AU - Elmore, Susan A. T2 - TOXICOLOGIC PATHOLOGY AB - A critical event in embryo development is the proper formation of the vascular system, of which the hepatobiliary system plays a pivotal role. This has led researchers to use transgenic mice to identify the critical steps involved in developmental disorders associated with the hepatobiliary vascular system. Vascular development is dependent upon normal vasculogenesis, angiogenesis, and the transformation of vessels into their adult counterparts. Any alteration in vascular development has the potential to cause deformities or embryonic death. Numerous publications describe specific stages of vascular development relating to various organs, but a single resource detailing the stage-by-stage development of the vasculature pertaining to the hepatobiliary system has not been available. This comprehensive histology atlas provides hematoxylin & eosin and immunohistochemical-stained sections of the developing mouse blood and lymphatic vasculature with emphasis on the hepatobiliary system between embryonic days (E) 11.5-18.5 and the early postnatal period. Additionally, this atlas includes a 3-dimensional video representation of the E18.5 mouse venous vasculature. One of the most noteworthy findings of this atlas is the identification of the portal sinus within the mouse, which has been erroneously misinterpreted as the ductus venosus in previous publications. Although the primary purpose of this atlas is to identify normal hepatobiliary vascular development, potential embryonic abnormalities are also described. DA - 2016/7// PY - 2016/7// DO - 10.1177/0192623316630836 VL - 44 IS - 5 SP - 705-725 SN - 1533-1601 KW - vascular development KW - lymphatic development KW - hepatobiliary development KW - portal sinus KW - embryo KW - mouse KW - atlas ER - TY - JOUR TI - Development and Genetic Characterization of an Advanced Backcross-Nested Association Mapping (AB-NAM) Population of Wild x Cultivated Barley AU - Nice, Liana M. AU - Steffenson, Brian J. AU - Brown-Guedira, Gina L. AU - Akhunov, Eduard D. AU - Liu, Chaochih AU - Kono, Thomas J. Y. AU - Morrell, Peter L. AU - Blake, Thomas K. AU - Horsley, Richard D. AU - Smith, Kevin P. AU - Muehlbauer, Gary J. T2 - GENETICS AB - The ability to access alleles from unadapted germplasm collections is a long-standing problem for geneticists and breeders. Here we developed, characterized, and demonstrated the utility of a wild barley advanced backcross-nested association mapping (AB-NAM) population. We developed this population by backcrossing 25 wild barley accessions to the six-rowed malting barley cultivar Rasmusson. The 25 wild barley parents were selected from the 318 accession Wild Barley Diversity Collection (WBDC) to maximize allelic diversity. The resulting 796 BC2F4:6 lines were genotyped with 384 SNP markers, and an additional 4022 SNPs and 263,531 sequence variants were imputed onto the population using 9K iSelect SNP genotypes and exome capture sequence of the parents, respectively. On average, 96% of each wild parent was introgressed into the Rasmusson background, and the population exhibited low population structure. While linkage disequilibrium (LD) decay (r(2) = 0.2) was lowest in the WBDC (0.36 cM), the AB-NAM (9.2 cM) exhibited more rapid LD decay than comparable advanced backcross (28.6 cM) and recombinant inbred line (32.3 cM) populations. Three qualitative traits: glossy spike, glossy sheath, and black hull color were mapped with high resolution to loci corresponding to known barley mutants for these traits. Additionally, a total of 10 QTL were identified for grain protein content. The combination of low LD, negligible population structure, and high diversity in an adapted background make the AB-NAM an important tool for high-resolution gene mapping and discovery of novel allelic variation using wild barley germplasm. DA - 2016/7// PY - 2016/7// DO - 10.1534/genetics.116.190736 VL - 203 IS - 3 SP - 1453-+ SN - 1943-2631 KW - wild barley KW - advanced backcross KW - nested association mapping population KW - association mapping KW - plant genetic resources KW - Multiparent Advanced Generation Inter-Cross (MAGIC) KW - multiparental populations KW - MPP ER - TY - JOUR TI - Winter legume cover-crop root decomposition and N release dynamics under disking and roller-crimping termination approaches AU - Jani, Arun D. AU - Grossman, Julie AU - Smyth, Thomas J. AU - Hu, Shuijin T2 - RENEWABLE AGRICULTURE AND FOOD SYSTEMS AB - Abstract Several approaches can be used to terminate legume cover crops in the spring prior to planting summer crops, but the effect that these methods have on decomposition and nitrogen (N) release dynamics of legume cover-crop roots is poorly understood. The main objectives of this study were to: (i) quantify decomposition and N release of roots from pea ( Pisum sativum ), clover ( Trifolium incarnatum ) and vetch ( Vicia villosa Roth); (ii) determine if roots decompose and release N faster when cover crops are terminated by disking compared with roller-crimping; and (iii) determine if roots decompose and release N faster under higher soil inorganic N levels. Two field experiments were conducted in Goldsboro and Kinston, North Carolina in the summer of 2012. Cover crops at these sites were terminated in spring by disking or roller-crimping and planted to unirrigated corn. Air-dried roots placed in litterbags were buried in their corresponding cover-crop plots and in plots where cover crops had not been grown that had either synthetic N fertilizer added at burial or had no fertilizer addition. Root litterbags were collected over 16 weeks at both sites. Cover-crop plots terminated by disking had up to 117 and 49% higher soil inorganic N than roller-crimped plots in Goldsboro and Kinston, respectively. However, roots did not appear to contribute significantly to these increases, as measured root decomposition and N release was not affected by termination approach at either site. Roots decomposed rapidly at both sites, losing up to 65% of their original biomass within 4 weeks after burial. Root N release was also rapid at both sites, with vetch generally releasing N fastest and clover slowest. It was estimated that cover-crop roots supplied 47–62 and 19–33 kg N ha −1 during the corn cycle in Goldsboro and Kinston, respectively. Our results indicate that under the warm, humid summer conditions of the Southeastern USA, legume cover-crop roots decompose and release N rapidly. DA - 2016/6// PY - 2016/6// DO - 10.1017/s1742170515000113 VL - 31 IS - 3 SP - 214-229 SN - 1742-1713 KW - legume cover crops KW - roots KW - roller-crimping KW - disking KW - decomposition KW - soil nitrogen ER - TY - JOUR TI - The impact of seed size and chemical composition on seedling vigor, yield, and fiber quality of cotton in five production environments AU - Snider, John L. AU - Collins, Guy D. AU - Whitaker, Jared AU - Chapman, Kent D. AU - Horn, Patrick T2 - FIELD CROPS RESEARCH AB - Seed mass and oil content of the quiescent cotton seed are positively associated with seedling vigor. In contrast, seed size has been negatively associated with lint yield due to selection for cultivars with greater lint percent. The current study addressed the hypothesis that planting seed mass and total oil + protein calorie content of the quiescent cotton seed would be strongly predictive of seedling vigor across most field conditions and that the impact of seed traits on yield would be dependent upon yield environment. When considered in each yield environment, seedling vigor was positively associated with seed size and the total oil + protein calorie content per seed in four out five environments tested. Regression analysis of cultivar mean oil + protein kcal content per seed versus seedling vigor across all environments indicated a strong, positive relationship between the two parameters (r2 = 0.65). Although lint percent was positively correlated with lint yield in every environment, planting seed mass and calorie content were not correlated with lint yield in four of the five environments tested or when cultivar means for lint yield and seed characteristics were averaged across all environments. Thus, it is concluded that individual planting seed mass and total energy content for oil + protein are strong predictors of early seedling vigor. Furthermore, selecting commercially available cultivars with characteristics indicative of seedling vigor does not appear to limit lint yield in most environments tested. DA - 2016/7// PY - 2016/7// DO - 10.1016/j.fcr.2016.05.002 VL - 193 SP - 186-195 SN - 1872-6852 KW - Seedling vigor KW - Seed mass KW - Seed composition KW - Lint yield KW - Gossypium hirsutum ER - TY - JOUR TI - Role of Conservation Adoption Premiums on Participation in Water Quality Trading Programs AU - Motallebi, Marzieh AU - O'Connell, Caela AU - Hoag, Dana L. AU - Osmond, Deanna L. T2 - WATER AB - Over half of lakes, reservoirs, and ponds in the United States are threatened or impaired, mostly by nutrients. One policy to improve water quality is water quality trading (WQT). While the concept is appealing, adoption of conservation practices in these programs has been anemic at best. Using a case study in the newly-formed WQT market in Jordan Lake, North Carolina, we propose that part of the problem is a large adoption premium (AP) for this program. AP is the amount that farmers require over and above direct adoption costs to participate. In this study, farmers were asked at in-person interviews about their willingness to accept (WTA) a payment to adopt a particular conservation practice (riparian buffers) in order to generate and sell credits. We compared farmers’ WTA to their direct cost of participation, which allowed us to estimate an AP. On average, the AP more than doubles the cost of purchasing credits. The AP sums all of the known indirect costs already cited in the literature, and more, into a single value and is relatively simple to estimate. Knowing the AP would improve the ability of policy makers to accurately estimate what is needed to boost adoption rates in WQT programs and other conservation programs as well. DA - 2016/6// PY - 2016/6// DO - 10.3390/w8060245 VL - 8 IS - 6 SP - SN - 2073-4441 KW - water quality trading KW - conservation practices KW - wedges KW - adoption premium KW - farmer decision-making KW - Jordan Lake ER - TY - JOUR TI - Phosphorus dynamics in Swedish agricultural soils as influenced by fertilization and mineralogical properties: Insights gained from batch experiments and XANES spectroscopy AU - Eriksson, Ann Kristin AU - Hesterberg, Dean AU - Klysubun, Wantana AU - Gustafsson, Jon Petter T2 - SCIENCE OF THE TOTAL ENVIRONMENT AB - The soil chemistry of phosphorus (P) is important for understanding the processes governing plant availability as well as the risk of environmental losses of P. The objective of this research was to investigate both the speciation and the pH-dependent solubility patterns of P in clayey agricultural soils in relation to soil mineralogy and fertilization history. The study focused on soil samples from six fields that were subjected to different P fertilization regimes for periods of 45 to 57years. Soil P speciation was analyzed by P K-edge XANES spectroscopy and chemical fractionation, sorption isotherms were constructed, and dissolved P was measured as a function of pH. The XANES fitting results showed that organic P and P adsorbed to Fe and Al (hydr)oxides were common P constituents in all soils. Calcium phosphates were identified in five of six soil samples. The XANES results also indicated an increase in P adsorbed to Al and to a lesser extent Fe (hydr)oxides as a result of fertilization. Moreover, the fluorescence intensity from the P K-edge XANES analysis was most strongly correlated with HCl-digestible P (r=0.81***). Consistent with the XANES analysis, laboratory sorption isotherm models showed that the Freundlich sorption coefficient (KF) was most closely related to oxalate-extractable Al. Greater proportions of Ca phosphate in two of the heavily fertilized soils in combination with enhanced PO4 solubilization upon sample acidification indicated neoformation of Ca-phosphate precipitates. The results for the unfertilized soil samples generally showed a minimum in dissolved PO4 between pH6.5 and 7.5, with increases particularly at lower pH. This behavior can be explained either by the dissolution of Al-hydroxide-type sorbents or Ca phosphates at lower pH. In fertilized soils, there was no consistent trend in pH-dependent solubilization of P, with a complex relationship to solid-phase speciation. To conclude, inorganic P species changed most dynamically in agricultural clay soils over a period of several decades, and the role of pH in the solubilization of P depended mainly on P fertilization history and the content of reactive Ca phosphates. DA - 2016/10/1/ PY - 2016/10/1/ DO - 10.1016/j.scitotenv.2016.05.225 VL - 566 SP - 1410-1419 SN - 1879-1026 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84989879198&partnerID=MN8TOARS KW - XANES spectroscopy KW - Phosphorus KW - Phosphate KW - Apatite KW - Secondary iron and aluminium (hydr)oxides KW - Clay mineralogy ER - TY - JOUR TI - Meta-analysis to refine map position and reduce confidence intervals for delayed-canopy-wilting QTLs in soybean AU - Hwang, Sadal AU - King, C. Andy AU - Chen, Pengyin AU - Ray, Jeffery D. AU - Cregan, Perry B. AU - Carter, Thomas E., Jr. AU - Li, Zenglu AU - Abdel-Haleem, Hussein AU - Matson, Kevin W. AU - Schapaugh, William, Jr. AU - Purcell, Larry C. T2 - MOLECULAR BREEDING DA - 2016/7// PY - 2016/7// DO - 10.1007/s11032-016-0516-5 VL - 36 IS - 7 SP - SN - 1572-9788 KW - Drought stress KW - Meta-analysis KW - QTL KW - Soybean KW - Wilting ER - TY - JOUR TI - Fomesafen Programs for Palmer Amaranth (Amaranthus palmeri) Control in Sweetpotato AU - Barkley, Susan L. AU - Chaudhari, Sushila AU - Jennings, Katherine M. AU - Schultheis, Jonathan R. AU - Meyers, Stephen L. AU - Monks, David W. T2 - WEED TECHNOLOGY AB - Studies were conducted in 2012 and 2013 to determine the effect of fomesafen based Palmer amaranth control program in ‘Covington' and ‘Evangeline' sweetpotato cultivars. Treatments consisted of fomesafen pretransplant alone at 0.20, 0.28, 0.36, 0.42, 0.56, and 0.84 kg ai ha −1 or followed by (fb) S -metolachlor at 1.12 kg ai ha −1 0 to 7 d after transplanting (DAP), fomesafen at 0.28 kg ha −1 fb S -metolachlor at 1.12 kg ha −1 14 DAP, flumioxazin pretransplant at 0.105 kg ai ha −1 , S -metolachlor at 1.12 kg ha −1 0 to 7 DAP, clomazone at 0.63 kg ha −1 0 to 7 DAP, napropamide at 2.24 kg ha −1 0 to7 DAP, flumioxazin fb S -metolachlor 0 to 7 DAP, and flumioxazin fb clomazone fb S -metolachlor 14 DAP. Fomesafen pretransplant at 0.28 to 0.84 kg ha −1 alone or followed by S -metolachlor at 1.12 kg ha −1 0 to 7 DAP provided 80 to 100% Palmer amaranth control without reduction of yield and significant (< 13%) injury in Covington and Evangeline sweetpotato. Flumioxazin alone or fb S -metolachlor and flumioxazin fb clomazone fb S -metolachlor provided Palmer amaranth control (≥ 95%) with little injury (≤ 5%) and similar yield to the weed-free check. Clomazone alone did not cause injury, but controlled only 24 to 32% of Palmer amaranth at 50 DAP, which resulted in reduced no. 1, marketable, and total sweetpotato yield. Napropamide provided inconsistent control of Palmer amaranth in both years; therefore jumbo and total sweetpotato yield was reduced as compared to the weed-free check in 2012. Palmer amaranth control, sweetpotato cultivar tolerance, and yield in treatments with fomesafen fb S -metolachlor were similar to flumioxazin fb S -metolachlor. In conclusion, a herbicide program consisting of pretransplant fomesafen (0.28 to 0.42 kg ha −1 ) fb S -metolachlor (1.12 kg ha −1 ) is a potential option to control Palmer amaranth without causing significant injury and yield reduction in sweetpotato. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00150.1 VL - 30 IS - 2 SP - 506-515 SN - 1550-2740 KW - Application rate KW - crop tolerance KW - herbicide KW - weed control ER - TY - JOUR TI - Expression of a constitutively active nitrate reductase variant in tobacco reduces tobacco-specific nitrosamine accumulation in cured leaves and cigarette smoke AU - Lu, Jianli AU - Zhang, Leichen AU - Lewis, Ramsey S. AU - Bovet, Lucien AU - Goepfert, Simon AU - Jack, Anne M. AU - Crutchfield, James D. AU - Ji, Huihua AU - Dewey, Ralph E. T2 - PLANT BIOTECHNOLOGY JOURNAL AB - Burley tobaccos (Nicotiana tabacum) display a nitrogen-use-deficiency phenotype that is associated with the accumulation of high levels of nitrate within the leaf, a trait correlated with production of a class of compounds referred to as tobacco-specific nitrosamines (TSNAs). Two TSNA species, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN), have been shown to be strong carcinogens in numerous animal studies. We investigated the potential of molecular genetic strategies to lower nitrate levels in burley tobaccos by overexpressing genes encoding key enzymes of the nitrogen-assimilation pathway. Of the various constructs tested, only the expression of a constitutively active nitrate reductase (NR) dramatically decreased free nitrate levels in the leaves. Field-grown tobacco plants expressing this NR variant exhibited greatly reduced levels of TSNAs in both cured leaves and mainstream smoke of cigarettes made from these materials. Decreasing leaf nitrate levels via expression of a constitutively active NR enzyme represents an exceptionally promising means for reducing the production of NNN and NNK, two of the most well-documented animal carcinogens found in tobacco products. DA - 2016/7// PY - 2016/7// DO - 10.1111/pbi.12510 VL - 14 IS - 7 SP - 1500-1510 SN - 1467-7652 KW - nitrate reductase KW - tobacco KW - tobacco-specific nitrosamines KW - burley KW - nitrogen-assimilation pathway KW - NNN KW - NNK ER - TY - JOUR TI - Evolution of phosphorus speciation with depth in an agricultural soil profile AU - Eriksson, Ann Kristin AU - Hillier, Stephen AU - Hesterberg, Dean AU - Klysubun, Wantana AU - Ulen, Barbro AU - Gustafsson, Jon Petter T2 - GEODERMA AB - With time, different soil-forming processes such as weathering, plant growth, accumulation of organic matter, and cultivation are likely to affect phosphorus (P) speciation. In this study, the depth distribution of P species was investigated for an agricultural clay soil, Lanna, Sweden. Small amounts of apatite-P was demonstrated in the topsoil whereas the speciation of P at 70–100 cm depth consisted of approximately 86% apatite according to P K-edge XANES (X-ray absorption near-edge structure) spectroscopy. Because there were only minor differences in bulk mineralogy and texture, these variations in P speciation were interpreted as the result of apatite weathering of the topsoil. Speciation modeling on soil extracts supported this idea: hydroxyapatite was not thermodynamically stable in the top 50 cm of the soil. Apatite was enriched in the bulk soil relative to the clay fraction, as expected during apatite dissolution. Combined results from batch experiments, XANES spectroscopy and X-ray diffraction suggested chemical transformations of the topsoil as a result from accumulation of organic matter and airing from tillage followed by enhanced weathering of apatite, amphiboles, clay minerals, and iron oxides. This caused the formation of poorly crystalline secondary iron and aluminum (hydr)oxides in the topsoil, which retained part of the released P from apatite. Other P was incorporated into organic forms. Furthermore, the results also showed that short-term acidification below the current pH value (below 5.5 in the topsoil and 7.2 in the deeper subsoil) caused significant solubilization of P. This is attributed to two different mechanisms: the instability of Al-containing sorbents (e.g. Al hydroxides) at low pH (in the topsoil), and the acid-mediated dissolution of apatite (the subsoil). DA - 2016/10/15/ PY - 2016/10/15/ DO - 10.1016/j.geoderma.2016.06.004 VL - 280 SP - 29-37 SN - 1872-6259 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84974653012&partnerID=MN8TOARS KW - Acidification KW - Apatite KW - Clay KW - Secondary iron and aluminum (hydr)oxides KW - X-ray adsorption spectroscopy ER - TY - JOUR TI - Effect of Indaziflam Applications on 'Tifway 419' Bermudagrass Growth AU - Jeffries, Matthew D. AU - Gannon, Travis W. AU - Ou, Ling T2 - AGRONOMY JOURNAL AB - Indaziflam { N ‐[(1R, S )‐2,3‐dihyrdo‐2,6‐dimethyl‐1 H ‐inden‐1‐yl]‐6‐(1‐fluorethyl)1,3,5‐triazine‐2,4‐diamine} is a preemergence herbicide for annual weed control in turfgrass systems. Following indaziflam U.S. registration in 2010, sporadic cases of hybrid bermudagrass (HB) injury were reported. Field research was conducted from 2012 to 2014 evaluating indaziflam application rates [16 followed by 16 (28 d), 33, 49, or 65 g a.i. ha −1 ] and timings (fall‐only, fall‐plus‐spring, or spring‐only) in two environments (reduced sunlight [RS] and full sunlight [FS]) to elucidate their effect on HB growth. In Year 1, differences were not detected, while in Year 2 HB cover varied between environments. In Year 2, HB cover in the RS environment treated with 49 and 65 g ha −1 had 36 and 64% less visual cover 12 wk after initial spring treatment than the FS environment, respectively. Within the RS environment, indaziflam also reduced HB visual cover compared to the nontreated (77% cover). A bioassay study conducted with soil cores collected from field plots suggested HB cover reduction was minimally affected by indaziflam‐soil bioavailability, as perennial ryegrass biomass was not reduced beyond a 2.5‐cm depth. Weather conditions varied between years, with air temperatures ≤0°C occurring more frequently and to a greater magnitude in Year 2. The weather, coupled with reduced solar radiation in the RS environment may have contributed to HB cover reduction in Year 2. Overall, indaziflam applications to established HB in areas with suitable growth conditions were safe; however, unacceptable HB cover reductions were observed in areas with poor growth conditions. Indaziflam is safe on established bermudagrass grown in appropriate conditions. Bermudagrass‐indaziflam tolerance decreased when applied in a reduced sunlight setting. Severe winter climatic conditions exacerbated bermudagrass‐indaziflam injury. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2015.0352 VL - 108 IS - 3 SP - 950-956 SN - 1435-0645 ER - TY - JOUR TI - Critical Period for Weed Control in Grafted and Nongrafted Fresh Market Tomato AU - Chaudhari, Sushila AU - Jennings, Katherine M. AU - Monks, David W. AU - Jordan, David L. AU - Gunter, Christopher C. AU - McGowen, Samuel J. AU - Louws, Frank J. T2 - WEED SCIENCE AB - Field experiments were conducted to determine the critical period for weed control (CPWC) in nongrafted ‘Amelia’ and Amelia grafted onto ‘Maxifort’ tomato rootstock grown in plasticulture. The establishment treatments (EST) consisted of two seedlings each of common purslane, large crabgrass, and yellow nutsedge transplanted at 1, 2, 3, 4, 5, 6, and 12 wk after tomato transplanting (WAT) and remained until tomato harvest to simulate weeds emerging at different times. The removal treatments (REM) consisted of the same weeds transplanted on the day of tomato transplanting and removed at 2, 3, 4, 5, 6, 8, and 12 WAT to simulate weeds controlled at different times. The beginning and end of the CPWC, based on a 5% yield loss of marketable tomato, was determined by fitting log-logistic and Gompertz models to the relative yield data representing REM and EST, respectively. In both grafted and nongrafted tomato, plant aboveground dry biomass increased as establishment of weeds was delayed and tomato plant biomass decreased when removal of weeds was delayed. For a given time of weed removal and establishment, grafted tomato plants produced higher biomass than nongrafted. The delay in establishment and removal of weeds resulted in weed biomass decrease and increase of the same magnitude, respectively, regardless of transplant type. The predicted CPWC was from 2.2 to 4.5 WAT in grafted tomato and from 3.3 to 5.8 WAT in nongrafted tomato. The length (2.3 or 2.5 wk) of the CPWC in fresh market tomato was not affected by grafting; however, the CPWC management began and ended 1 wk earlier in grafted tomato than in nongrafted tomato. DA - 2016/// PY - 2016/// DO - 10.1614/ws-d-15-00049.1 VL - 64 IS - 3 SP - 523-530 SN - 1550-2759 KW - Competition KW - establishment KW - grafted tomato KW - interference KW - removal ER - TY - JOUR TI - Call to Action on Herbicide Resistance Management AU - Coble, Harold D. AU - Schroeder, Jill T2 - WEED SCIENCE AB - Management of herbicide resistance can be most effectively accomplished if every person and organization involved in agricultural production takes an ownership position and participates in solving the growing problem of weed resistance to herbicides. Growers and other pest management practitioners are keys to effective herbicide resistance management since they make the final decisions on practices used. However, many other people and organizations have an important role to play as well. Agricultural input supply networks, including chemical companies, are a widely used information source for growers' decisions through company marketing efforts. Government agencies may influence decisions through regulations or incentive programs. University scientists through their research, education, and outreach programs may impact management decisions, and organizations such as professional societies, farm and commodity groups, public interest organizations, and the agricultural press play roles as well. It is critically important that all of these groups impacting herbicide resistance management decisions are sending the same message and that message is based on sound science. The time to act is now. DA - 2016/// PY - 2016/// DO - 10.1614/ws-d-15-00032.1 VL - 64 SP - 661-666 SN - 1550-2759 KW - Agricultural community KW - best management practice KW - evolved resistance KW - mechanism of action KW - selection pressure ER - TY - JOUR TI - Bioaccumulation Dynamics of Arsenate at the Base of Aquatic Food Webs AU - Lopez, Adeline R. AU - Hesterberg, Dean R. AU - Funk, David H. AU - Buchwalter, David B. T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Periphyton is an important food source at the base of freshwater ecosystems that tends to bioconcentrate trace elements making them trophically available. The potential for arsenic-a trace element of particular concern due to its widespread occurrence, toxicity, and carcinogenicity-to bioconcentrate in periphyton and thus be available to benthic grazers is less well characterized. To better understand arsenate bioaccumulation dynamics in lotic food webs, we used a radiotracer approach to characterize accumulation in periphyton and subsequent trophic transfer to benthic grazers. Periphyton bioconcentrated As between 3,200-9,700-fold (dry weight) over 8 days without reaching steady state, suggesting that periphyton is a major sink for arsenate. However, As-enriched periphyton as a food source for the mayfly Neocloeon triangulifer resulted in negligible As accumulation in a full lifecycle exposure. Additional studies estimate dietary assimilation efficiency in several primary consumers ranging from 22% in the mayfly N. triangulifer to 75% in the mayfly Isonychia sp. X-ray fluorescence mapping revealed that As was predominantly associated with iron oxides in periphyton. We speculate that As adsorption to Fe in periphyton may play a role in reducing dietary bioavailability. Together, these results suggest that trophic movement of As in lotic food webs is relatively low, though species differences in bioaccumulation patterns are important. DA - 2016/6/21/ PY - 2016/6/21/ DO - 10.1021/acs.est.6b01453 VL - 50 IS - 12 SP - 6556-6564 SN - 1520-5851 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84975471905&partnerID=MN8TOARS ER - TY - JOUR TI - Allergenicity attributes of different peanut market types AU - Koppelman, Stef J. AU - Jayasena, Shyamali AU - Luykx, Dion AU - Schepens, Erik AU - Apostolovic, Danijela AU - Jong, Govardus A. H. AU - Isleib, Thomas G. AU - Nordlee, Julie AU - Baumert, Joe AU - Taylor, Steve L. AU - Cheng, Hsiaopo AU - Maleki, Soheila T2 - FOOD AND CHEMICAL TOXICOLOGY AB - Four different market classes of peanut (Runner, Virginia Spanish, and Valencia) are commonly consumed in Western countries, but for some consumers peanuts are a main cause of food-induced anaphylaxis. Limited information is available on the comparative allergenicity of these distinct market classes. The aim of this study was to compare allergenicity attributes of different peanut cultivars. The protein content and protein profiles were highly comparable for all tested cultivars. All cultivar samples contained the major allergens Ara h 1, Ara h 2, Ara h 3 and Ara h 6, as assessed by SDS-PAGE and RP-HPLC, although some minor differences in major allergen content were found between samples. All samples were reactive in commercial ELISAs for detection and quantification of peanut protein. IgE-binding potency differed between samples with a maximum factor of 2, indicating a highly comparable allergenicity. Based on our observations, we conclude that peanuts from the main market types consumed in Western countries are highly comparable in their allergenicity attributes, indicating that safety considerations with regard to peanut allergy are not dependent on the peanut cultivar in question. DA - 2016/5// PY - 2016/5// DO - 10.1016/j.fct.2016.02.016 VL - 91 SP - 82-90 SN - 1873-6351 KW - Peanut KW - Arachis hypogaea KW - Allergen KW - Immunoassay KW - IgE ER - TY - JOUR TI - Sensible Heat Balance Estimates of Transient Soil Ice Contents AU - Kojima, Yuki AU - Heitman, Joshua L. AU - Flerchinger, Gerald N. AU - Ren, Tusheng AU - Horton, Robert T2 - Vadose Zone Journal AB - Core Ideas Soil ice content is difficult to quantify. A sensible heat balance with heat pulse probes may indicate soil ice contents. A sensible heat balance can determine transient soil ice content from −5 to 0°C. Soil ice contents below −5°C can be determined with heat capacity changes. Heat pulse probes can monitor soil ice contents at and below 0°C. Soil ice content is an important component for winter soil hydrology. The sensible heat balance (SHB) method using measurements from heat pulse probes (HPPs) is a possible way to determine transient soil ice content. In a previous study, in situ soil ice content estimates with the SHB method were inaccurate, due to thermal conductivity errors and the use of relatively long time steps for calculations. The objective of this study is to reexamine the SHB method for soil ice content determination. A soil freezing and thawing laboratory experiment was performed with soil columns and heat exchangers. Transient soil ice contents in the soil columns during soil freezing and thawing were determined with the SHB method. The SHB method was able to determine dynamic changes in soil ice contents during initial freezing and final thawing for soil temperatures between −5 and 0°C when latent heat values associated with ice formation or with thawing were relatively large. During an extended freezing period, when soil temperatures were below −5°C, the small associated latent heat fluxes were below the sensitivity of the SHB method, and the SHB method did not provide accurate estimates of ice contents with time. However, the soil ice contents during the extended freezing period could be estimated well from changes in volumetric heat capacity ( C ) determined with HPP. Thus, combining the SHB method for initial freezing and final thawing, with a change in C method for extended freezing periods, allowed determination of dynamic soil ice contents for the entire range of freezing and thawing soil temperatures investigated. HPPs were able to measure soil ice contents. DA - 2016/5// PY - 2016/5// DO - 10.2136/vzj2015.10.0134 VL - 15 IS - 5 SP - vzj2015.10.0134 J2 - Vadose Zone Journal LA - en OP - SN - 1539-1663 UR - http://dx.doi.org/10.2136/vzj2015.10.0134 DB - Crossref ER - TY - JOUR TI - QTL and major genes influencing grain yield potential in soft red winter wheat adapted to the southern United States AU - Addison, Christopher K. AU - Mason, R. Esten AU - Brown-Guedira, Gina AU - Guedira, Mohammed AU - Hao, Yuanfeng AU - Miller, Randall G. AU - Subramanian, Nithya AU - Lozada, Dennis N. AU - Acuna, Andrea AU - Arguello, Maria N. AU - Johnson, Jerry W. AU - Ibrahim, Amir M. H. AU - Sutton, Russell AU - Harrison, Stephen A. T2 - EUPHYTICA DA - 2016/6// PY - 2016/6// DO - 10.1007/s10681-016-1650-1 VL - 209 IS - 3 SP - 665-677 SN - 1573-5060 KW - Genotype by environmental interaction KW - QTL mapping KW - Quantitative trait locus KW - Yield ER - TY - JOUR TI - Poultry Manure Nitrogen Availability Influences Winter Wheat Yield and Yield Components AU - Savala, Canon E. N. AU - Crozier, Carl R. AU - Smyth, T. Jot T2 - AGRONOMY JOURNAL AB - Standard poultry manure use recommendations in North Carolina consider waste analysis but not differences among manure types, cropping seasons, or application timing. This study evaluated poultry manure source, N rate strategy, and application time effects on soft red winter wheat ( Triticum aestivum L.) tiller density, yield components, grain yield, and N availability coefficients. Coefficients included fertilizer N equivalence based on grain yield and plant‐available N based on aboveground plant N content. Four field experiments used broiler litter (BL) and composted layer manure (CLM), two rates (67 and 134 kg total‐N ha −1 ), and three different application times (incorporated in October preplant, Feekes’ 3 in December/January, or Feekes’ 4 in February). Dual‐source treatments received 67 kg N ha −1 of manure plus 67 kg N ha −1 as urea ammonium nitrate (UAN) solution at Feekes’ 5. Fertilizer‐N (UAN) rate treatments (0, 39, 78, 117, and 156 kg N ha −1 ) were also included. Yields responded to N inputs but were lowest when BL and CLM were applied at 67 kg N ha −1 either preplant or at Feekes’ 3. Grain yield and N availability were greater with CLM than with BL (3.0 vs. 2.8 t ha −1 grain and 58 vs. 52 kg ha −1 N uptake, respectively). Availability coefficients ranged from 12 to 32%, lower than the standard assumed values of 50 to 60%. The feasible poultry manure application window includes preplant until Feekes’ 4, but fertilizing winter wheat crops solely with poultry manure may supply less N than intended. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2015.0355 VL - 108 IS - 2 SP - 864-872 SN - 1435-0645 ER - TY - JOUR TI - Measuring maturity in cotton cultivar trials AU - Bowman, D. T. AU - Bourland, F. AU - Kuraparthy, V. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 1 SP - 40-45 ER - TY - JOUR TI - Leaf ontogeny strongly influences photosynthetic tolerance to drought and high temperature in Gossypium hirsutum AU - Chastain, Daryl R. AU - Snider, John L. AU - Choinski, John S. AU - Collins, Guy D. AU - Perry, Calvin D. AU - Whitaker, Jared AU - Grey, Timothy L. AU - Sorensen, Ronald B. AU - Iersel, Marc AU - Byrd, Seth A. AU - Porter, Wesley T2 - JOURNAL OF PLANT PHYSIOLOGY AB - Temperature and drought are major abiotic limitations to crop productivity worldwide. While abiotic stress physiology research has focused primarily on fully expanded leaves, no studies have investigated photosynthetic tolerance to concurrent drought and high temperature during leaf ontogeny. To address this, Gossypium hirsutum plants were exposed to five irrigation treatments, and two different leaf stages were sampled on three dates during an abnormally dry summer. Early in the growing season, ontogenic PSII heat tolerance differences were observed. Photosystem II was more thermotolerant in young leaves than mature leaves. Later in the growing season, no decline in young leaf net photosynthesis (PN) was observed as leaf temperature increased from 31 to 37 °C, as average midday leaf water potential (ΨMD) declined from −1.25 to −2.03 MPa. In contrast, mature leaf PN declined 66% under the same conditions. Stomatal conductance (gs) accounted for 84–98% of variability in leaf temperature, and gs was strongly associated with ΨMD in mature leaves but not in young leaves. We conclude that young leaves are more photosynthetically tolerant to heat and drought than mature leaves. Elucidating the mechanisms causing these ontogenic differences will likely help mitigate the negative impacts of abiotic stress in the future. DA - 2016/7// PY - 2016/7// DO - 10.1016/j.jplph.2016.05.003 VL - 199 SP - 18-28 SN - 1618-1328 KW - Gossypium hirsutum KW - Drought KW - Heat tolerance KW - Leaf expansion KW - Photosynthesisa ER - TY - JOUR TI - Influence of nitrogen and mepiquat chloride on cotton canopy reflectance measurements AU - Foote, W. AU - Edmisten, K. AU - Wells, R. AU - Collins, G. AU - Roberson, G. AU - Jordan, D. AU - Fisher, L. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 1 SP - 1-7 ER - TY - JOUR TI - Identification of maize-derived dominant gametophyte factors AU - Jones, Zachary G. AU - Goodman, Major M. AU - Krakowsky, Matthew D. T2 - EUPHYTICA DA - 2016/5// PY - 2016/5// DO - 10.1007/s10681-016-1635-0 VL - 209 IS - 1 SP - 63-69 SN - 1573-5060 KW - Dominant gametophyte factors KW - Plant breeding KW - Organic agriculture KW - Coexistence KW - Ga1-s KW - Tcb1 ER - TY - JOUR TI - Genome-Wide Association Mapping of Fusarium Head Blight Resistance in Wheat using Genotyping-by-Sequencing AU - Arruda, Marcio P. AU - Brown, Patrick AU - Brown-Guedira, Gina AU - Krill, Allison M. AU - Thurber, Carrie AU - Merrill, Keith R. AU - Foresman, Bradley J. AU - Kolb, Frederic L. T2 - PLANT GENOME AB - Fusarium head blight (FHB) is one of the most important wheat ( L.) diseases worldwide, and host resistance displays complex genetic control. A genome-wide association study (GWAS) was performed on 273 winter wheat breeding lines from the midwestern and eastern regions of the United States to identify chromosomal regions associated with FHB resistance. Genotyping-by-sequencing (GBS) was used to identify 19,992 single-nucleotide polymorphisms (SNPs) covering all 21 wheat chromosomes. Marker-trait associations were performed with different statistical models, the most appropriate being a compressed mixed linear model (cMLM) controlling for relatedness and population structure. Ten significant SNP-trait associations were detected on chromosomes 4A, 6A, 7A, 1D, 4D, and 7D, and multiple SNPs were associated with on chromosome 3B. Although combination of favorable alleles of these SNPs resulted in lower levels of severity (SEV), incidence (INC), and deoxynivalenol concentration (DON), lines carrying multiple beneficial alleles were in very low frequency for most traits. These SNPs can now be used for creating new breeding lines with different combinations of favorable alleles. This is one of the first GWAS using genomic resources from the International Wheat Genome Sequencing Consortium (IWGSC). DA - 2016/3// PY - 2016/3// DO - 10.3835/plantgenome2015.04.0028 VL - 9 IS - 1 SP - SN - 1940-3372 ER - TY - JOUR TI - Expanding Maize Genetic Resources with Predomestication Alleles: Maize-Teosinte Introgression Populations AU - Liu, Zhengbin AU - Cook, Jason AU - Melia-Hancock, Susan AU - Guill, Katherine AU - Bottoms, Christopher AU - Garcia, Arturo AU - Ott, Oliver AU - Nelson, Rebecca AU - Recker, Jill AU - Balint-Kurti, Peter AU - Larsson, Sara AU - Lepak, Nicholas AU - Buckler, Ed AU - Trimble, Loren AU - Tracy, William AU - McMullen, Michael D. AU - Flint-Garcia, Sherry A. T2 - PLANT GENOME AB - Teosinte ( subsp. H. H. Iltis & Doebley) has greater genetic diversity than maize inbreds and landraces ( subsp. ). There are, however, limited genetic resources to efficiently evaluate and tap this diversity. To broaden resources for genetic diversity studies in maize, we developed and evaluated 928 near-isogenic introgression lines (NILs) from 10 teosinte accessions in the B73 background. Joint linkage analysis of the 10 introgression populations identified several large-effect quantitative trait loci (QTL) for days to anthesis (DTA), kernel row number (KRN), and 50-kernel weight (Wt50k). Our results confirm prior reports of kernel domestication loci and identify previously uncharacterized QTL with a range of allelic effects enabling future research into the genetic basis of these traits. Additionally, we used a targeted set of NILs to validate the effects of a KRN QTL located on chromosome 2. These introgression populations offer novel tools for QTL discovery and validation as well as a platform for initiating fine mapping. DA - 2016/3// PY - 2016/3// DO - 10.3835/plantgenome2015.07.0053 VL - 9 IS - 1 SP - SN - 1940-3372 ER - TY - JOUR TI - Effects of HCl pretreatment, drying, and storage on the stable isotope ratios of soil and sediment samples AU - Kim, Min-Seob AU - Lee, Won-Seok AU - Kumar, K. Suresh AU - Shin, Kyung-Hoon AU - Robarge, Wayne AU - Kim, Minseok AU - Lee, Sang Ryong T2 - RAPID COMMUNICATIONS IN MASS SPECTROMETRY AB - Rationale Stable isotope (δ 13 C, δ 15 N, δ 34 S values) analysis has become increasingly important for tracing contaminant sources in environments. Pretreatment of environmental samples allows accurate analysis of stable isotope ratios. The pretreatment of a sample and its subsequent preservation could either contaminate or create experimental artifacts affecting the validity of the resulting C/N ratios and the elemental isotopic contents of a sample. Methods The effects of acid pretreatment (0.1, 0.5, 1, 2, 5, 13 M HCl) and exposure period (2, 6, 12, 24, and 48 h) on the stable isotopic ratios of marine sediment (MS), river sediment (RS) and terrestrial soil (TS) samples were evaluated. The effects of storage temperatures (–80, –20 and 2°C), storage duration (1 week, 1 to 12 months) and washing steps (1, 2, 3, 5, 7 or 12 times) on the stable isotopic ratios were also considered. The %C, %N and %S, as well as the δ 13 C, δ 15 N, and δ 34 S values, of each sample were measured using continuous flow Elemental Analyzer/Isotope Ratio Mass Spectrometry (EA/IRMS). Results The HCl treatment was applicable for δ 13 C analysis. However, the acid concentration and duration of exposure that brought about total removal of carbonate for the three sample types varied; e.g. the TS sample required stronger acid and a shorter exposure time. Storage time also had an effect: the δ 13 C values were lower and the δ 15 N and δ 34 S values higher after storage for 300 days. Conclusions HCl pretreatment effectively eliminates carbonates and thereby helps δ 13 C analysis of the organic fraction. HCl pretreatment is not recommended for δ 15 N and δ 34 S analysis. Freeze‐drying of samples is recommended rather than oven drying. A temperature‐dependent change in the isotopic ratios of long‐term stored samples was observed during this study; therefore, relatively short‐term storage (–80°C) of freeze‐dried samples is preferable. Copyright © 2016 John Wiley & Sons, Ltd. DA - 2016/7/15/ PY - 2016/7/15/ DO - 10.1002/rcm.7600 VL - 30 IS - 13 SP - 1567-1575 SN - 1097-0231 ER - TY - JOUR TI - Determination of Biosolids Phosphorus Solubility and Its Relationship to Wastewater Treatment AU - Jameson, Molly AU - White, Jeffrey G. AU - Osmond, Deanna L. AU - Aziz, Tarek T2 - WATER ENVIRONMENT RESEARCH AB - ABSTRACT: In North Carolina (NC), biosolids land application rates governed by crop nitrogen (N) requirements typically surpass crop phosphorus (P) needs, increasing surface water pollution potential. The NC Department of Environmental Quality (NCDEQ) is considering P‐based biosolids application guidelines for some nutrient‐impaired watersheds using the P Loss Assessment Tool (PLAT), but important biosolids information is lacking: total P (TP), water‐extractable P (WEP), and percent water‐extractable P (PWEP). In each of three seasons, we sampled 28 biosolids from 26 participating water resource recovery facilities (WRRFs) and analyzed for TP, WEP, and percent dry matter (DM), from which PWEP and nonsoluble P were calculated. Based on descriptive statistics and an online survey of treatment processes, biosolids were divided into Class A‐alkaline, Class A‐heat, Class B‐slurry, and Class B‐cake. The average TP in Class A alkaline stabilized biosolids was more than five times less than the average of the other biosolids, 5.0 vs. 26.6 g/kg, respectively. Averaged over biosolids, WEP and PWEP were 1.4 g/kg and 5.0%, respectively. Stabilization processes appeared to reduce WEP substantially, so biosolids potential soluble‐P loss is low. Our data will allow PLAT to be used for biosolids P‐loss risk assessments. DA - 2016/7/1/ PY - 2016/7/1/ DO - 10.2175/106143016x14609975746406 VL - 88 IS - 7 SP - 602-610 SN - 1554-7531 KW - biosolids KW - phosphorus content KW - water extractable phosphorus KW - land application KW - stabilization processes KW - wastewater ER - TY - JOUR TI - Comparative Structural and Computational Analysis Supports Eighteen Cellulose Synthases in the Plant Cellulose Synthesis Complex AU - Nixon, B. Tracy AU - Mansouri, Katayoun AU - Singh, Abhishek AU - Du, Juan AU - Davis, Jonathan K. AU - Lee, Jung-Goo AU - Slabaugh, Erin AU - Vandavasi, Venu Gopal AU - O’Neill, Hugh AU - Roberts, Eric M. AU - Roberts, Alison W. AU - Yingling, Yaroslava G. AU - Haigler, Candace H. T2 - Scientific Reports AB - A six-lobed membrane spanning cellulose synthesis complex (CSC) containing multiple cellulose synthase (CESA) glycosyltransferases mediates cellulose microfibril formation. The number of CESAs in the CSC has been debated for decades in light of changing estimates of the diameter of the smallest microfibril formed from the β-1,4 glucan chains synthesized by one CSC. We obtained more direct evidence through generating improved transmission electron microscopy (TEM) images and image averages of the rosette-type CSC, revealing the frequent triangularity and average cross-sectional area in the plasma membrane of its individual lobes. Trimeric oligomers of two alternative CESA computational models corresponded well with individual lobe geometry. A six-fold assembly of the trimeric computational oligomer had the lowest potential energy per monomer and was consistent with rosette CSC morphology. Negative stain TEM and image averaging showed the triangularity of a recombinant CESA cytosolic domain, consistent with previous modeling of its trimeric nature from small angle scattering (SAXS) data. Six trimeric SAXS models nearly filled the space below an average FF-TEM image of the rosette CSC. In summary, the multifaceted data support a rosette CSC with 18 CESAs that mediates the synthesis of a fundamental microfibril composed of 18 glucan chains. DA - 2016/6// PY - 2016/6// DO - 10.1038/srep28696 VL - 6 IS - 1 SP - J2 - Sci Rep LA - en OP - SN - 2045-2322 UR - http://dx.doi.org/10.1038/srep28696 DB - Crossref ER - TY - JOUR TI - The valine and lysine residues in the conserved FxVTxK motif are important for the function of phylogenetically distant plant cellulose synthases AU - Slabaugh, Erin AU - Scavuzzo-Duggan, Tess AU - Chaves, Arielle AU - Wilson, Liza AU - Wilson, Carmen AU - Davis, Jonathan K. AU - Cosgrove, Daniel J. AU - Anderson, Charles T. AU - Roberts, Alison W. AU - Haigler, Candace H. T2 - GLYCOBIOLOGY AB - Cellulose synthases (CESAs) synthesize the β-1,4-glucan chains that coalesce to form cellulose microfibrils in plant cell walls. In addition to a large cytosolic (catalytic) domain, CESAs have eight predicted transmembrane helices (TMHs). However, analogous to the structure of BcsA, a bacterial CESA, predicted TMH5 in CESA may instead be an interfacial helix. This would place the conserved FxVTxK motif in the plant cell cytosol where it could function as a substrate-gating loop as occurs in BcsA. To define the functional importance of the CESA region containing FxVTxK, we tested five parallel mutations in Arabidopsis thaliana CESA1 and Physcomitrella patens CESA5 in complementation assays of the relevant cesa mutants. In both organisms, the substitution of the valine or lysine residues in FxVTxK severely affected CESA function. In Arabidopsis roots, both changes were correlated with lower cellulose anisotropy, as revealed by Pontamine Fast Scarlet. Analysis of hypocotyl inner cell wall layers by atomic force microscopy showed that two altered versions of Atcesa1 could rescue cell wall phenotypes observed in the mutant background line. Overall, the data show that the FxVTxK motif is functionally important in two phylogenetically distant plant CESAs. The results show that Physcomitrella provides an efficient model for assessing the effects of engineered CESA mutations affecting primary cell wall synthesis and that diverse testing systems can lead to nuanced insights into CESA structure–function relationships. Although CESA membrane topology needs to be experimentally determined, the results support the possibility that the FxVTxK region functions similarly in CESA and BcsA. DA - 2016/5// PY - 2016/5// DO - 10.1093/glycob/cwv118 VL - 26 IS - 5 SP - 509-519 SN - 1460-2423 KW - cellulose synthesis KW - gametophore formation KW - phenotypic complementation KW - root elongation KW - site-directed mutagenesis ER - TY - JOUR TI - Profitability of Integrated Management of Fusarium Head Blight in North Carolina Winter Wheat AU - Cowger, Christina AU - Weisz, Randy AU - Arellano, Consuelo AU - Murphy, Paul T2 - PHYTOPATHOLOGY AB - Fusarium head blight (FHB) is one of the most difficult small-grain diseases to manage, due to the partial effectiveness of management techniques and the narrow window of time in which to apply fungicides profitably. The most effective management approach is to integrate cultivar resistance with FHB-specific fungicide applications; yet, when forecasted risk is intermediate, it is often unclear whether such an application will be profitable. To model the profitability of FHB management under varying conditions, we conducted a 2-year split-plot field experiment having as main plots high-yielding soft red winter wheat cultivars, four moderately resistant (MR) and three susceptible (S) to FHB. Subplots were sprayed at flowering with Prosaro or Caramba, or left untreated. The experiment was planted in seven North Carolina environments (location–year combinations); three were irrigated to promote FHB development and four were not irrigated. Response variables were yield, test weight, disease incidence, disease severity, deoxynivalenol (DON), Fusarium-damaged kernels, and percent infected kernels. Partial profits were compared in two ways: first, across low-, medium-, or high-DON environments; and second, across environment–cultivar combinations divided by risk forecast into “do spray” and “do not spray” categories. After surveying DON and test weight dockage among 21 North Carolina wheat purchasers, three typical market scenarios were used for modeling profitability: feed-wheat, flexible (feed or flour), and the flour market. A major finding was that, on average, MR cultivars were at least as profitable as S cultivars, regardless of epidemic severity or market. Fungicides were profitable in the feed-grain and flexible markets when DON was high, with MR cultivars in the flexible or flour markets when DON was intermediate, and on S cultivars aimed at the flexible market. The flour market was only profitable when FHB was present if DON levels were intermediate and cultivar resistance was combined with a fungicide. It proved impossible to use the risk forecast to predict profitability of fungicide application. Overall, the results indicated that cultivar resistance to FHB was important for profitability, an FHB-targeted fungicide expanded market options when risk was moderate or high, and the efficacy of fungicide decision-making is reduced by factors that limit the accuracy of risk forecasts. DA - 2016/8// PY - 2016/8// DO - 10.1094/phyto-10-15-0263-r VL - 106 IS - 8 SP - 814-823 SN - 1943-7684 ER - TY - JOUR TI - Probing the biological sources of soil N2O emissions by quantum cascade laser-based N-15 isotopocule analysis AU - Chen, Huaihai AU - Williams, David AU - Walker, John T. AU - Shi, Wei T2 - SOIL BIOLOGY & BIOCHEMISTRY AB - Isotopocule analysis by quantum cascade laser spectrometry (QCL) is a promising approach for in situ, real-time tracking of the biological sources of soil N2O emissions. However, background atmospheric N2O is an important source of variability in the measurement of isotopocule ratios (i.e., 14N15N16O/14N14N16O and 15N14N16O/14N14N16O) of gas samples. Here, a method based on Keeling plot for determining the intramolecular 15N distribution in N2O is introduced. The sensitivity and reliability of this method are examined against N2O of known 15N site preference (SP), and N2O produced from fungal and bacterial isolates, soils with different moisture contents and organic amendments, and a soil chamber under field conditions. The isotopocules of N2O determined by standard gases supported that the Keeling plot method was more reliable than the averaging method. Using this method, SP of N2O was greater in fungal than bacterial denitrifiers, as well as in soil at 60% water filled pore space (WFPS) than 80–100% WFPS. This method also determined that the SP of N2O was distinct between soils of different substrate complexity. Further, we observed a N2O SP between −18.9‰ and 2.2% in a soil flux chamber deployed in a corn field after 2 d of rainfalls that is consistent with the SP of N2O produced from bacterial denitrification and nitrifier denitrification. Our data demonstrate that this Keeling plot method provides accurate discrimination of biological sources when N2O is analyzed by the QCL system. DA - 2016/9// PY - 2016/9// DO - 10.1016/j.soilbio.2016.06.015 VL - 100 SP - 175-181 SN - 1879-3428 KW - Nitrous oxide KW - Isotopocule KW - Isotopic site-preference KW - Quantum cascade laser spectrometer ER - TY - JOUR TI - Population Genomics Related to Adaptation in Elite Oat Germplasm AU - Klos, Kathy Esvelt AU - Huang, Yung-Fen AU - Bekele, Wubishet A. AU - Obert, Don E. AU - Babiker, Ebrahiem AU - Beattie, Aaron D. AU - Bjornstad, Asmund AU - Bonman, J. Michael AU - Carson, Martin L. AU - Chao, Shiaoman AU - Gnanesh, Belaghihalli N. AU - Griffiths, Irene AU - Harrison, Stephen A. AU - Howarth, Catherine J. AU - Hu, Gongshe AU - Ibrahim, Amir AU - Islamovic, Emir AU - Jackson, Eric W. AU - Jannink, Jean-Luc AU - Kolb, Frederic L. AU - McMullen, Michael S. AU - Fetch, Jennifer Mitchell AU - Murphy, J. Paul AU - Ohm, Herbert W. AU - Rines, Howard W. AU - Rossnagel, Brian G. AU - Schlueter, Jessica A. AU - Sorrells, Mark E. AU - Wight, Charlene P. AU - Yan, Weikai AU - Tinker, Nicholas A. T2 - PLANT GENOME AB - Six hundred thirty five oat ( L.) lines and 4561 single-nucleotide polymorphism (SNP) loci were used to evaluate population structure, linkage disequilibrium (LD), and genotype-phenotype association with heading date. The first five principal components (PCs) accounted for 25.3% of genetic variation. Neither the eigenvalues of the first 25 PCs nor the cross-validation errors from = 1 to 20 model-based analyses suggested a structured population. However, the PC and = 2 model-based analyses supported clustering of lines on spring oat vs. southern United States origin, accounting for 16% of genetic variation ( < 0.0001). Single-locus -statistic () in the highest 1% of the distribution suggested linkage groups that may be differentiated between the two population subgroups. Population structure and kinship-corrected LD of = 0.10 was observed at an average pairwise distance of 0.44 cM (0.71 and 2.64 cM within spring and southern oat, respectively). On most linkage groups LD decay was slower within southern lines than within the spring lines. A notable exception was found on linkage group Mrg28, where LD decay was substantially slower in the spring subpopulation. It is speculated that this may be caused by a heterogeneous translocation event on this chromosome. Association with heading date was most consistent across location-years on linkage groups Mrg02, Mrg12, Mrg13, and Mrg24. DA - 2016/7// PY - 2016/7// DO - 10.3835/plantgenome2015.10.0103 VL - 9 IS - 2 SP - SN - 1940-3372 ER - TY - JOUR TI - Heading Date QTL in Winter Wheat (Triticum aestivum L.) Coincide with Major Developmental Genes VERNALIZATION1 and PHOTOPERIOD1 AU - Guedira, Mohammed AU - Xiong, Mai AU - Hao, Yuan Feng AU - Johnson, Jerry AU - Harrison, Steve AU - Marshall, David AU - Brown-Guedira, Gina T2 - PLOS ONE AB - In wheat (Triticum aestivum L.), time from planting to spike emergence is influenced by genes controlling vernalization requirement and photoperiod response. Characterizing the available genetic diversity of known and novel alleles of VERNALIZATION1 (VRN1) and PHOTOPERIOD1 (PPD1) in winter wheat can inform approaches for breeding climate resilient cultivars. This study identified QTL for heading date (HD) associated with multiple VRN1 and PPD1 loci in a population developed from a cross between two early flowering winter wheat cultivars. When the population was grown in the greenhouse after partial vernalization treatment, major heading date QTLs co-located with the VRN-A1 and VRN-B1 loci. Copy number variation at the VRN-A1 locus influenced HD such that RIL having three copies required longer cold exposure to transition to flowering than RIL having two VRN-A1 copies. Sequencing vrn-B1 winter alleles of the parents revealed multiple polymorphisms in the first intron that were the basis of mapping a major HD QTL coinciding with VRN-B1. A 36 bp deletion in the first intron of VRN-B1 was associated with earlier HD after partial vernalization in lines having either two or three haploid copies of VRN-A1. The VRN1 loci interacted significantly and influenced time to heading in field experiments in Louisiana, Georgia and North Carolina. The PPD1 loci were significant determinants of heading date in the fully vernalized treatment in the greenhouse and in all field environments. Heading date QTL were associated with alleles having large deletions in the upstream regions of PPD-A1 and PPD-D1 and with copy number variants at the PPD-B1 locus. The PPD-D1 locus was determined to have the largest genetic effect, followed by PPD-A1 and PPD-B1. Our results demonstrate that VRN1 and PPD1 alleles of varying strength allow fine tuning of flowering time in diverse winter wheat growing environments. DA - 2016/5/10/ PY - 2016/5/10/ DO - 10.1371/journal.pone.0154242 VL - 11 IS - 5 SP - SN - 1932-6203 ER - TY - JOUR TI - Expression of the shrimp antimicrobial peptide penaeidin 4-1 confers resistance against brown patch disease in tall fescue AU - Zhou, Binbin AU - Luo, Hong AU - Qu, Rongda T2 - PLANT CELL TISSUE AND ORGAN CULTURE DA - 2016/6// PY - 2016/6// DO - 10.1007/s11240-016-0963-z VL - 125 IS - 3 SP - 599-603 SN - 1573-5044 KW - Brown patch KW - Disease resistance KW - Penaeidin KW - Rhizoctonia solani subgroups KW - Tall fescue ER - TY - JOUR TI - Effects of Nitrogen and Shading on Root Morphologies, Nutrient Accumulation, and Photosynthetic Parameters in Different Rice Genotypes AU - Pan, Shenggang AU - Liu, Haidong AU - Mo, Zhaowen AU - Patterson, Bob AU - Duan, Meiyang AU - Tian, Hua AU - Hu, Shuijing AU - Tang, Xiangru T2 - SCIENTIFIC REPORTS AB - Abstract Nitrogen availability and illumination intensity are two key factors which affect rice growth. However, their influences on total nitrogen accumulation, photosynthetic rate, root morphologies, and yields are not fully understood. We conducted two field experiments to (1) evaluate the effects of shading under different N treatments on photosynthetic parameters, root morphologies, total nutrient accumulation, and grain yields of rice; and (2) elucidate the relationship between total nutrient accumulation and root morphologies under different shading conditions and nitrogen treatments. Three nitrogen rates, three shading treatments, and three different rice cultivars were used in two field experiments. Double shading during the grain-filling stage decreased total nutrient accumulation, altered root morphological characteristics, and decreased yields in rice. There were also significant interaction effects between nitrogen and shading on photosynthetic rate, transpiration rate, and total root length, root superficial area, and root volume. Significant interactions were found among cultivars and shading for photosynthetic rate and transpiration rate. Correlation analysis revealed that total nitrogen accumulation (TNA) and potassium accumulation (TKA) were significantly positively correlated with total root length, root superficial area, and root volume. N application could alleviate the detrimental effects of shading on total nutrient accumulation and grain yield in rice. DA - 2016/8/25/ PY - 2016/8/25/ DO - 10.1038/srep32148 VL - 6 SP - SN - 2045-2322 ER - TY - JOUR TI - Chemical controls on abiotic and biotic release of geogenic arsenic from Pleistocene aquifer sediments to groundwater AU - Gillispie, Elizabeth C. AU - Andujar, Erika AU - Polizzotto, Matthew L. T2 - ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS AB - Over 150 million people in South and Southeast Asia consume unsafe drinking water from arsenic-rich Holocene aquifers. Although use of As-free water from Pleistocene aquifers is a potential mitigation strategy, such aquifers are vulnerable to geogenic As pollution, placing millions more people at potential risk. The goal of this research was to define chemical controls on abiotic and biotic release of geogenic As to groundwater. Batch incubations of sediments with natural chemical variability from a Pleistocene aquifer in Cambodia were conducted to evaluate how interactions among arsenic, manganese and iron oxides, and dissolved and sedimentary organic carbon influenced As mobilization from sediments. The addition of labile dissolved organic carbon produced the highest concentrations of dissolved As after >7 months, as compared to sediment samples incubated with sodium azide or without added carbon, and the extent of As release was positively correlated with the percent of initial extractable Mn released from the sediments. The mode of As release was impacted by the source of DOC supplied to the sediments, with biological processes responsible for 81% to 85% of the total As release following incubations with lactate and acetate but only up to 43% to 61% of the total As release following incubations with humic and fulvic acids. Overall, cycling of key redox-active elements and organic-carbon reactivity govern the potential for geogenic As release to groundwater, and results here may be used to formulate better predictions of the arsenic pollution potential of aquifers in South and Southeast Asia. DA - 2016/8/1/ PY - 2016/8/1/ DO - 10.1039/c6em00359a VL - 18 IS - 8 SP - 1090-1103 SN - 2050-7895 ER - TY - JOUR TI - Assessment of trace element impacts on agricultural use of water from the Dan River following the Eden coal ash release AU - Hesterberg, Dean AU - Polizzotto, Matthew L. AU - Crozier, Carl AU - Austin, Robert E. T2 - INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT AB - Catastrophic events require rapid, scientifically sound decision making to mitigate impacts on human welfare and the environment. The objective of this study was to analyze potential impacts of coal ash-derived trace elements on agriculture following a 35,000-tonne release of coal ash into the Dan River at the Duke Energy Steam Station in Eden, North Carolina. We performed scenario calculations to assess the potential for excessive trace element loading to soils via irrigation and flooding with Dan River water, uptake of trace elements by crops, and livestock consumption of trace elements via drinking water. Concentrations of 13 trace elements measured in Dan River water samples within 4 km of the release site declined sharply after the release and were equivalent within 5 d to measurements taken upriver. Mass-balance calculations based on estimates of soil trace-element concentrations and the nominal river water concentrations indicated that irrigation or flooding with 25 cm of Dan River water would increase soil concentrations of all trace elements by less than 0.5%. Calculations of potential increases of trace elements in corn grain and silage, fescue, and tobacco leaves suggested that As, Cr, Se, Sr, and V were elements of most concern. Concentrations of trace elements measured in river water following the ash release never exceeded adopted standards for livestock drinking water. Based on our analyses, we present guidelines for safe usage of Dan River water to diminish negative impacts of trace elements on soils and crop production. In general, the approach we describe here may serve as a basis for rapid assessment of environmental and agricultural risks associated with any similar types of releases that arise in the future. DA - 2016/4// PY - 2016/4// DO - 10.1002/ieam.1669 VL - 12 IS - 2 SP - 353-363 SN - 1551-3793 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84941010545&partnerID=MN8TOARS KW - Coal ash KW - Trace elements KW - Soil contamination KW - Rapid assessment KW - Water quality KW - Mass-balance calculation ER - TY - JOUR TI - Variation Among Maize Hybrids in Response to High Vapor Pressure Deficit at High Temperatures AU - Shekoofa, Avat AU - Sinclair, Thomas R. AU - Messina, Carlos D. AU - Cooper, Mark T2 - CROP SCIENCE AB - ABSTRACT Temperature and vapor pressure deficit (VPD) are two important environmental factors influencing stomatal conductance and transpiration. A limited transpiration rate (TR lim ) trait expressed under high VPD has been shown to offer an approach to increase crop yield in water‐limited areas. The benefit of the TR lim trait is that it lowers the effective VPD under which plants lose water and so conserves soil water to support crop growth for use during drought periods later in the growing season. Previous studies at moderate temperatures (32°C and lower) identified 12 maize ( Zea mays L.) hybrids that express the TR lim trait. A critical question is whether the TR lim trait is also expressed by these hybrids under temperatures up to 38°C, which are relevant in environments where maize may be grown. Five hybrids failed to express the TR lim trait at 38°C but seven hybrids had sustained expression of the trait at 38°C. The loss of expression of the TR lim response in the five hybrids was found to occur in the very narrow range of temperature increase from 36 to 38°C. The genetic differences in water use among these maize hybrids could be useful in selecting hybrids that are especially well adapted for temperature conditions in a targeted production area. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.02.0134 VL - 56 IS - 1 SP - 392-396 SN - 1435-0653 ER - TY - JOUR TI - Silver and zinc inhibitors influence transpiration rate and aquaporin transcript abundance in intact soybean plants AU - Devi, M. Jyostna AU - Sinclair, Thomas R. AU - Taliercio, Earl T2 - ENVIRONMENTAL AND EXPERIMENTAL BOTANY AB - Soybean genotype PI 416937 has previously been found to have low leaf hydraulic conductivity, which was hypothesized to be the basis for limited transpiration (TRlim) rates under high vapor pressure deficit. Previous studies with de-rooted shoots showed there was a consistency in the expression of TRlim and plant response to exposure to silver, an aquaporin (AQP) inhibitor. However, it is not clear what confounding influence treatments with metal AQP inhibitors may have on AQP transcript expression. This study was undertaken to extend the observations of response to silver and zinc using intact plants. In a comparison of four genotypes, intact plants of PI 416937 were uniquely insensitive to exposure to silver and of PI 471938 were uniquely insensitive to zinc. RNA abundance of eight AQPs was measured after treatment with the AQP inhibitors. There were differences in the abundance of RNA among genotypes. There was a general trend of less change in abundance in PI 416937 following silver treatment in contrast to increased abundance in the other genotypes. This result would be consistent with little or no response in transpiration rate in the intact plants of PI 416937 following silver treatment. Following zinc treatment, there was a rapid increase in RNA abundance in PI 471938 in comparison to the other genotypes. However, the changes in AQP abundance following treatment with metal inhibitors indicates the likely interaction of direct response of AQP to metals and alternation of expression of AQP transcripts. These results indicate that the results from treatment with metal inhibitors should likely be considered only as preliminary screens from which genotypes need to be tested directly for the TRlim trait. DA - 2016/2// PY - 2016/2// DO - 10.1016/j.envexpbot.2015.10.006 VL - 122 SP - 168-175 SN - 1873-7307 KW - Aquaporins KW - Silver KW - Soybean KW - Transpiration KW - Vapor pressure deficit KW - Zinc ER - TY - JOUR TI - Responses to Recurrent Index Selection for Reduced Fusarium Ear Rot and Lodging and for Increased Yield in Maize AU - Horne, David W. AU - Eller, Magen S. AU - Holland, James B. T2 - CROP SCIENCE AB - ABSTRACT Fusarium ear rot, caused by the pathogen Fusarium verticillioides , damages maize ( Zea mays L.) grain production and is associated with contamination of grain by fumonisin, a mycotoxin harmful to both humans and animals. Recurrent selection may be an effective way to combine improvements in resistance to Fusarium ear rot with improved grain yield and lodging resistance. To test this hypothesis, three cycles of recurrent index selection based on evaluating S 0:1 lines for Fusarium ear rot, grain yield, and lodging were implemented in a genetically broad‐based population. Direct intrapopulation response to selection in the target traits was measured by comparing lines sampled from Cycle 0 and Cycle 3 populations. In addition, indirect response for fumonisin contamination was also measured along with indirect response for agronomic traits when crossed to commercial inbred tester, FR1064. Results indicate significant direct gain from selection for Fusarium ear rot, but no significant gains for yield or lodging resistance. Indirect gains were also observed for Fusarium ear rot resistance in topcrosses to an unrelated tester line and for fumonisin contamination both within the selection population and in topcrosses. Our results are the first demonstration of the indirect effect of selection against Fusarium ear rot on reduction of fumonisin contamination. Heritabilities for target traits did not decrease over generations, indicating potential for further genetic gain from selection in this population. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.06.0333 VL - 56 IS - 1 SP - 85-94 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84952760963&partnerID=MN8TOARS ER - TY - JOUR TI - Response of seven aquatic plants to a new arylpicolinate herbicide AU - Richardson, R. J. AU - Haug, E. J. AU - Netherland, M. D. T2 - Journal of Aquatic Plant Management DA - 2016/// PY - 2016/// VL - 54 SP - 26-31 ER - TY - JOUR TI - Plants and the changing environment AU - De Kok, L. J. AU - Grantz, D. A. AU - Burkey, K. O. T2 - PLANT BIOLOGY AB - Plant BiologyVolume 18, Issue S1 p. 3-4 Editorial Plants and the changing environment L. J. De Kok, L. J. De Kok [email protected] Laboratory of Plant Physiology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, P.O. Box 11103, 9700 CC Groningen, The NetherlandsSearch for more papers by this authorD. A. Grantz, D. A. Grantz [email protected] Department of Botany and Plant Sciences, University of California, Riverside, Parlier, 93648 CA, USASearch for more papers by this authorK. O. Burkey, K. O. Burkey [email protected] U.S. Department of Agriculture, Agricultural Research Service, Plant Science Research, Department of Crop Science, North Carolina State University, 3127 Ligon Street, Raleigh, 27607 NC, USASearch for more papers by this author L. J. De Kok, L. J. De Kok [email protected] Laboratory of Plant Physiology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, P.O. Box 11103, 9700 CC Groningen, The NetherlandsSearch for more papers by this authorD. A. Grantz, D. A. Grantz [email protected] Department of Botany and Plant Sciences, University of California, Riverside, Parlier, 93648 CA, USASearch for more papers by this authorK. O. Burkey, K. O. Burkey [email protected] U.S. Department of Agriculture, Agricultural Research Service, Plant Science Research, Department of Crop Science, North Carolina State University, 3127 Ligon Street, Raleigh, 27607 NC, USASearch for more papers by this author First published: 12 December 2015 https://doi.org/10.1111/plb.12413Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. References Burkhardt J., Pariyar S. (2016) How does the VDP response of isohydric and anisohydric plants depend on leaf surface particles? 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(2016) Photosynthetic traits of Siebold's beech seedlings in changing light conditions by removal of shading trees under elevated CO2. Plant Biology, 18 (Suppl. 1), 56– 62. Citing Literature Volume18, IssueS1Special Issue: PLANTS AND THE CHANGING ENVIRONMENTJanuary 2016Pages 3-4 ReferencesRelatedInformation DA - 2016/1// PY - 2016/1// DO - 10.1111/plb.12413 VL - 18 SP - 3-4 SN - 1438-8677 ER - TY - JOUR TI - Monoecious hydrilla-A review of the literature AU - True-Meadows, S. AU - Haug, E. J. AU - Richardson, R. J. T2 - Journal of Aquatic Plant Management DA - 2016/// PY - 2016/// VL - 54 SP - 1-11 ER - TY - JOUR TI - Monoecious hydrilla tuber dynamics following various management regimes on four North Carolina reservoirs AU - Nawrocki, J. J. AU - Richardson, R. J. AU - Hoyle, S. T. T2 - Journal of Aquatic Plant Management DA - 2016/// PY - 2016/// VL - 54 SP - 12-19 ER - TY - JOUR TI - Long-Term Management of Palmer Amaranth (Amaranthus palmeri) in Dicamba-Tolerant Cotton AU - Inman, M. D. AU - Jordan, D. L. AU - York, A. C. AU - Jennings, Katherine AU - Monks, D. W. AU - Everman, W. J. AU - Bollman, S. L. AU - Fowler, J. T. AU - Cole, R. M. AU - Soteres, J. K. AU - al. T2 - WEED SCIENCE AB - Research was conducted from 2011 to 2014 to determine weed population dynamics and frequency of glyphosate-resistant (GR) Palmer amaranth with herbicide programs consisting of glyphosate, dicamba, and residual herbicides in dicamba-tolerant cotton. Five treatments were maintained in the same plots over the duration of the experiment: three sequential POST applications of glyphosate with or without pendimethalin plus diuron PRE; three sequential POST applications of glyphosate plus dicamba with and without the PRE herbicides; and a POST application of glyphosate plus dicamba plus acetochlor followed by one or two POST applications of glyphosate plus dicamba without PRE herbicides. Additional treatments included alternating years with three sequential POST applications of glyphosate only and glyphosate plus dicamba POST with and without PRE herbicides. The greatest population of Palmer amaranth was observed when glyphosate was the only POST herbicide throughout the experiment. Although diuron plus pendimethalin PRE in a program with only glyphosate POST improved control during the first 2 yr, these herbicides were ineffective by the final 2 yr on the basis of weed counts from soil cores. The lowest population of Palmer amaranth was observed when glyphosate plus dicamba were applied regardless of PRE herbicides or inclusion of acetochlor POST. Frequency of GR Palmer amaranth was 8% or less when the experiment was initiated. Frequency of GR Palmer amaranth varied by herbicide program during 2012 but was similar among all herbicide programs in 2013 and 2014. Similar frequency of GR Palmer amaranth across all treatments at the end of the experiment most likely resulted from pollen movement from Palmer amaranth treated with glyphosate only to any surviving female plants regardless of PRE or POST treatment. These data suggest that GR Palmer amaranth can be controlled by dicamba and that dicamba is an effective alternative mode of action to glyphosate in fields where GR Palmer amaranth exists. DA - 2016/// PY - 2016/// DO - 10.1614/ws-d-15-00058.1 VL - 64 IS - 1 SP - 161-169 SN - 1550-2759 KW - Herbicide resistance management KW - herbicide-resistant weeds KW - soil seedbank ER - TY - JOUR TI - Identification of Alleles Conferring Resistance to Gray Leaf Spot in Maize Derived from its Wild Progenitor Species Teosinte AU - Lennon, Jill R. AU - Krakowsky, Matthew AU - Goodman, Major AU - Flint-Garcia, Sherry AU - Balint-Kurti, Peter J. T2 - CROP SCIENCE AB - ABSTRACT Gray leaf spot (GLS; causal agent Cercospora zeae‐maydis and Cercospora zeina ) is an important maize ( Zea mays L.) disease in the United States. Current control methods for GLS include using resistant cultivars, crop rotation, chemical applications, and conventional tillage to reduce inoculum levels. Teosinte ( Z. mays subsp. parviglumis ) is the wild progenitor of maize and easily forms hybrids with current maize inbreds. The aims of this study were to identify alleles from teosinte that, when introduced into temperate maize germplasm, conferred significant levels of GLS resistance. A population of 693 BC 4 S 2 near isogenic lines (NILs), developed by crossing nine different teosinte accessions into the background of the maize inbred B73, were evaluated for GLS resistance in replicated field trials over 2 yr. Six markers significantly associated with GLS resistance were identified using 768 single nucleotide polymorphism (SNP) markers used to genotype this population. Twenty‐seven individual NILs that differed significantly from B73 for GLS resistance and that carried teosinte introgressions at the significantly associated SNPs at bins 2.04, 3.06, 4.07, 5.03, 8.06, and 9.03 were selected for follow‐up studies. F 2:3 populations were developed by crossing each selected NIL to B73 followed by self‐pollinating the progeny twice. These F 2:3 populations were evaluated for GLS resistance and genotyped at the loci of interest. In most cases, single‐marker analysis validated predicted allelic substitution effects from the original NIL populations. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2014.07.0468 VL - 56 IS - 1 SP - 209-218 SN - 1435-0653 ER - TY - JOUR TI - Genetic Characterization of the North Carolina State University Maize Lines AU - Nelson, P. T. AU - Krakowsky, M. D. AU - Coles, N. D. AU - Holland, J. B. AU - Bubeck, D. M. AU - Smith, J. S. C. AU - Goodman, M. M. T2 - CROP SCIENCE AB - ABSTRACT Since 1980, 150 North Carolina State University (NCSU) maize ( Zea mays L.) inbreds have been developed and released on the basis of superior performance for topcross yield and other traits of agronomic importance. During this time, there has been great emphasis placed on breeding with exotic germplasm, with 86 NCSU inbreds having at least 50% exotic parentage and 40 of those having all‐tropical parentage. Maize germplasm released by NCSU represents a potentially useful resource for increasing maize diversity and performance in the United States. The objectives of this study were to characterize the genetic relationships among inbreds released from this unique breeding program and to compare them genetically with inbreds from other public and private breeding programs. The NCSU maize inbreds can be classified into five germplasm pools: Lancaster, Temperate‐adapted all tropical (TAAT), Lancaster × Tropical, Stiff Stalk, and Southern non‐Stiff Stalk; detailed analysis of pedigree records and molecular marker genotypes reveals additional substructure within each of these pools. There is general agreement among the four cluster analyses performed, three using single nucleotide polymorphism (SNP) data and one using pedigree‐derived coefficients of coancestry. We introduce a novel application of Procrustes analysis to identify disagreements between pedigree and marker similarities. The NCSU maize breeding germplasm includes diverse genetic backgrounds, as evidenced by the number of unique alleles compared with publically available inbreds from both public and off‐protection, private‐sector sources. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.09.0532 VL - 56 IS - 1 SP - 259-275 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84952837677&partnerID=MN8TOARS ER - TY - JOUR TI - Flocculated sediments can reduce the size of sediment basin at construction sites AU - Kang, Jihoon AU - King, Scott E. AU - McLaughlin, Richard A. T2 - JOURNAL OF ENVIRONMENTAL MANAGEMENT AB - Due to stringent water quality regulations on stormwater discharges, there is increasing interest in chemically-assisted settling of suspended sediments at construction sites. This study investigated settling characteristics of flocculated sediment by polyacrylamide (PAM) in a top-loading settling tube. Studied sediment materials were obtained from construction sites in North Carolina, USA: Coastal Plain loamy sand (CPLS), Piedmont sandy clay loam (PSCL), Piedmont silt loam (PSL), and Mountain clay loam (MCL). The four different sediment suspensions mixed with and without dissolved PAM were introduced to the top of the column individually. During a 1-h settling period, samples were taken at 1-m depth from surface at various times and analyzed for total suspended solids (TSS). Flocculated sediment by PAM greatly increased its settled TSS fraction up to 95-97% only in 1-min settling period compared to those of unflocculated sediment (16-72%). The settling improvement by PAM was profound in the finer-textured soils (PSL and MCL) by increasing their median particle settling velocity (>2 cm s(-1)) compared to unflocculated counterparts (<1.1 cm s(-1)). Estimated surface area requirement of sediment basin suggested that the basins receiving flocculated sediment could be reduced in size (surface area) by 2- to 4-times compared to those receiving unflocculated sediment. Our results suggests that current sediment basin design could be modified when chemically-assisted settling is implemented, taking up less space and cost in construction sites. DA - 2016/1/15/ PY - 2016/1/15/ DO - 10.1016/j.jenvman.2015.10.049 VL - 166 SP - 450-456 SN - 1095-8630 KW - Flocculation KW - Polyacrylamide KW - Sediment basin KW - Settling velocity KW - Total suspended solids ER - TY - JOUR TI - Determining Soil Bulk Density with Thermo-Time Domain Reflectometry: A Thermal Conductivity-Based Approach AU - Lu, Yili AU - Liu, Xiaona AU - Heitman, Joshua AU - Horton, Robert AU - Ren, Tusheng T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Core Ideas A method for monitoring soil bulk density from thermal conductivity and water content is provided. The new approach provides reliable bulk density data in both laboratory and field conditions. The new approach performs better than the heat capacity‐based method. The bulk density (ρ b ) of a tilled soil layer usually varies with depth and time. It is difficult to measure in situ ρ b with available instruments. Here we present a new approach that is capable of monitoring in situ ρ b based on thermal conductivity (λ) measurements. The proposed approach relies on an empirical model that relates λ to soil particle‐size distribution, ρ b , and volumetric water content (θ). The thermo‐time domain reflectometry (thermo‐TDR) sensor measures λ and θ simultaneously, and knowing soil texture a priori, ρ b is estimated using the empirical model. The approach was tested using datasets obtained on repacked and intact soil samples with a wide range of ρ b and θ. Further evaluations were made using in situ ρ b measurements with thermo‐TDR sensors in four tillage treatments. The laboratory results showed that the λ‐based thermo‐TDR method was able to provide reliable ρ b with root mean square errors (RMSE) within 0.17 g cm ‐3 . Under field conditions, the λ‐based thermo‐TDR method also provided accurate ρ b estimates with relative error generally within 10%. Under both laboratory and field conditions, the λ‐based thermo‐TDR method performed better than the heat capacity (C)‐based thermo‐TDR method. Differences were attributed mainly to C errors resulting from probe deflections, while λ measurements with the thermo‐TDR method were not affected by probe deflections. The λ‐based approach provides a way to obtain nondestructive, repeated, and in situ ρ b estimates with the thermo‐TDR method both in laboratory and field settings. DA - 2016/// PY - 2016/// DO - 10.2136/sssaj2015.08.0315 VL - 80 IS - 1 SP - 48-54 SN - 1435-0661 ER - TY - JOUR TI - Characterization of Two Adult-Plant Stripe Rust Resistance Genes on Chromosomes 3BS and 4BL in Soft Red Winter Wheat AU - Subramanian, Nithya K. AU - Mason, Richard Esten AU - Milus, Eugene A. AU - Moon, David E. AU - Brown-Guedira, Gina T2 - CROP SCIENCE AB - ABSTRACT Stripe rust, caused by Puccinia striiformis Westend. f. sp . tritici Erikss. ( Pst ) , is an important foliar disease of soft red winter wheat (SRWW) ( Triticum aestivum L.) in the eastern United States. However, very few resistance genes have been characterized in the SRWW germplasm pool. The SRWW line VA96W‐270 is known to be resistant to stripe rust race PST‐100, which was the predominant race in the United States from 2003 to 2006. To elucidate the genetic basis of resistance, a recombinant inbred line (RIL) population developed from a cross between VA96W‐270 and the susceptible cultivar Coker 9835 was evaluated for response to stripe rust infection in inoculated field nurseries over a 3‐yr period. The RIL population was then genotyped with stripe rust‐linked simple sequence repeat (SSR) markers and 90K single‐nucleotide polymorphism (SNP) markers. Two major quantitative trait loci (QTL) were identified, located on chromosomes 3BS and 4BL, both contributed by VA96W‐270. The 3BS and 4BL QTL explained up to 28 and 25% of the phenotypic variation for area under disease pressure curve (AUDPC), respectively. Recombinant inbred lines containing both QTL had average disease severity of 6%, compared with 38 to 45% for lines containing one of the two QTL and 69% for those containing neither QTL. Based on susceptibility of VA96W‐270 to infection at the seedling stage, the two genes appear to be associated with adult‐plant resistance. Markers associated with the two QTL were polymorphic in various wheat genotypes, suggesting they could be useful in marker‐assisted selection (MAS) to develop wheat cultivars with improved stripe rust resistance. DA - 2016/// PY - 2016/// DO - 10.2135/cropsci2015.01.0043 VL - 56 IS - 1 SP - 143-153 SN - 1435-0653 ER - TY - JOUR TI - Biochemical and physiological processes associated with the differential ozone response in ozone-tolerant and sensitive soybean genotypes AU - Chutteang, C. AU - Booker, F. L. AU - Na-Ngern, P. AU - Burton, A. AU - Aoki, M. AU - Burkey, K. O. T2 - PLANT BIOLOGY AB - Abstract Biochemical and physiological traits of two soybean [ Glycine max (L.) Merr.] genotypes differing in sensitivity to ozone (O 3 ) were investigated to determine the possible basis for the differential response. Fiskeby III (O 3 ‐tolerant) and Mandarin (Ottawa) (O 3 ‐sensitive) were grown in a greenhouse with charcoal‐filtered air for 4 weeks, then treated with O 3 for 7 h·day −1 in greenhouse chambers. Mandarin (Ottawa) showed significantly more leaf injury and hydrogen peroxide (H 2 O 2 ) and superoxide (O 2 − ) production compared with Fiskeby III . Peroxidase activity in Mandarin (Ottawa) was 31% higher with O 3 but was not significantly different in Fiskeby III . Ozone did not affect superoxide dismutase or glutathione reductase activities, or leaf concentrations of glutathione or ascorbic acid. Thus, variation in O 3 response between Fiskeby III and Mandarin (Ottawa) was not explained by differences in antioxidant enzymes and metabolites tested. Ethylene emission from leaves declined in Fiskeby III following O 3 exposure but not in Mandarin (Ottawa). Ozone exposure reduced quantum yield (Φ PSII ), electron transport rate ( ETR ) and photochemical quenching ( q p ) in Mandarin (Ottawa) more than in Fiskeby III , indicating that efficiency of energy conversion of PSII and photosynthetic electron transport was altered differently in the two genotypes. Short‐term exposure to O 3 had minimal effects on net carbon exchange rates of both soybean cultivars. A trend toward higher stomatal conductance in Mandarin (Ottawa) suggested stomatal exclusion might contribute to differential O 3 sensitivity of the two genotypes. Increased sensitivity of Mandarin (Ottawa) to O 3 was associated with higher H 2 O 2 and O 2 − production compared with Fiskeby III , possibly associated with genotype differences in stomatal function or regulation of ethylene during the initial phases of O 3 response. DA - 2016/1// PY - 2016/1// DO - 10.1111/plb.12347 VL - 18 SP - 28-36 SN - 1438-8677 KW - Antioxidants KW - ethylene KW - ozone tolerance KW - peroxidases KW - photosynthesis KW - soybean ER - TY - JOUR TI - Benchmark study on glyphosate-resistant cropping systems in the United States. Part 7: Effects of weed management strategy (grower practices versus academic recommendations) on the weed soil seedbank over 6 years AU - Gibson, David J. AU - Young, Bryan G. AU - Owen, Micheal D. K. AU - Gage, Karla L. AU - Matthews, Joseph L. AU - Jordan, David L. AU - Shaw, David R. AU - Weller, Stephen C. AU - Wilson, Robert G. T2 - PEST MANAGEMENT SCIENCE AB - Abstract BACKGROUND Shifts in weed species composition and richness resulting from near‐exclusive reliance on herbicides in glyphosate‐resistant ( GR ) cropping systems has necessitated the implementation of alternative weed management tactics to reduce selection pressures of herbicides. We contrasted the response of the weed soil seedbank to effects of weed management strategy, comparing grower practices with academic recommendations for best management practices ( BMPs ) over 6 years and across five weed hardiness zones in the US Midwest at sites subject to GR cropping systems. RESULTS Total weed population density and species richness varied according to cropping system, location and prior year's crop, but less so to weed management strategy. The seedbank population density for 11 of the 14 most frequent weed species was affected by weed management strategy either alone or in an interaction with hardiness zone or year, or both. In only 29% of comparisons was weed population density lower following academic recommendations, and this depended upon prior crop and cropping system. The population density of high‐risk weed species was reduced by academic recommendations, but only in two of six years and under continuous GR maize. Overall, the weed population density was decreasing in field halves subject to the BMPs in the academic recommendations relative to grower practices. CONCLUSION The soil seedbank is slow to respond to academic recommendations to mitigate glyphosate‐resistant weeds, but represents a biological legacy that growers need to keep in mind even when management practices reduce emerged field weed population densities. © 2015 Society of Chemical Industry DA - 2016/4// PY - 2016/4// DO - 10.1002/ps.4039 VL - 72 IS - 4 SP - 692-700 SN - 1526-4998 KW - corn KW - cotton KW - genetically engineered crops KW - genetically modified crops KW - herbicide-tolerant crops KW - herbicide-resistant weeds KW - maize KW - soybean KW - weed seedbank ER - TY - JOUR TI - Roadside soils show low plant available zinc and copper concentrations AU - Morse, Natalie AU - Walter, M. Todd AU - Osmond, Deanna AU - Hunt, William T2 - ENVIRONMENTAL POLLUTION AB - Vehicle combustion and component wear are a major source of metal contamination in the environment, which could be especially concerning where road ditches are actively farmed. The objective of this study was to assess how site variables, namely age, traffic (vehicles day−1), and percent carbon (%C) affect metal accumulation in roadside soils. A soil chronosequence was established with sites ranging from 3 to 37 years old and bioavailable, or mobile, concentrations of Zinc (Zn) and Copper (Cu) were measured along major highways in North Carolina using a Mehlich III extraction. Mobile Zn and Cu concentrations were low overall, and when results were scaled via literature values to “total metal”, the results were still generally lower than previous roadside studies. This could indicate farming on lands near roads would pose a low plant toxicity risk. Zinc and Cu were not correlated with annual average traffic count, but were positively correlated with lifetime traffic load (the product of site age and traffic count). This study shows an often overlooked variable, site age, should be included when considering roadside pollution accumulation. Zinc and Cu were more strongly associated with %C, than traffic load. Because vehicle combustion is also a carbon source, it is not obvious whether the metals and carbon are simply co-accumulating or whether the soil carbon in roadside soils may facilitate previously overlooked roles in sequestering metals on-site. DA - 2016/2// PY - 2016/2// DO - 10.1016/j.envpol.2015.11.011 VL - 209 SP - 30-37 SN - 1873-6424 KW - Highway KW - Zinc KW - Copper KW - Soil pollution KW - Traffic ER - TY - JOUR TI - Response of Eggplant (Solanum melongena) Grafted onto Tomato (Solanum lycopersicum) Rootstock to Herbicides AU - Chaudhari, Sushila AU - Jennings, Katherine M. AU - Monks, David W. AU - Jordan, David L. AU - Gunter, Christopher C. AU - Basinger, Nicholas T. AU - Louws, Frank J. T2 - WEED TECHNOLOGY AB - Tomato rootstocks have been successfully used for eggplant production. However, the safety of herbicides registered in tomato has not been tested on grafted eggplant, which is a combination of tomato rootstock and eggplant scion. Greenhouse and field experiments were conducted to determine response of grafted eggplant on tomato rootstock to napropamide, metribuzin, halosulfuron, trifluralin, S -metolachlor, and fomesafen herbicides. In greenhouse experiments, herbicide treatments included pretransplant S -metolachlor (400 and 800 g ai ha −1 ), pre- or posttransplant metribuzin (140 and 280 g ai ha −1 ), and posttransplant halosulfuron (18 and 36 g ai ha −1 ). In field experiments, herbicide treatments included pretransplant fomesafen (280 and 420 g ai ha −1 ), halosulfuron (39 and 52 g ha −1 ), metribuzin (280 and 550 g ha −1 ), napropamide (1,120 and 2,240 g ai ha −1 ), S -metolachlor (800 and 1,060 g ha −1 ), and trifluralin (560 and 840 g ai ha −1 ). The eggplant cultivar ‘Santana' was used as the scion and nongrafted control, and two hybrid tomatoes ‘RST-04−106-T' and ‘Maxifort' were used as rootstocks for grafted plants. In both greenhouse and field experiments, there was no difference between grafted and nongrafted eggplant in terms of injury caused by herbicides. Metribuzin posttransplant at 140 and 280 g ha −1 caused 94 and 100% injury to grafted and nongrafted eggplant 4 wk after treatment. In field experiments, pretransplant fomesafen, napropamide, S -metolachlor, and trifluralin caused less than 10% injury and no yield reduction in grafted and nongrafted eggplant. However, metribuzin caused injury and yield reduction in both grafted and nongrafted eggplant. Metribuzin at 550 g ha −1 caused 60 and 81% plant stand loss in 2013 and 2014, respectively. Halosulfuron reduced yield 24% in both grafted and nongrafted eggplant compared to nontreated control in 2013 but did not reduce yield in 2014. The pretransplant S -metolachlor, napropamide, fomesafen, and trifluralin are safe to use on eggplant grafted onto tomato rootstock, and will be a valuable addition to the toolkit of eggplant growers. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00079.1 VL - 30 IS - 1 SP - 207-216 SN - 1550-2740 KW - Application method KW - crop tolerance KW - grafting KW - rootstock ER - TY - JOUR TI - Mitigation Practices to Effectively Overseed into Indaziflam-Treated Turfgrass Areas AU - Jeffries, Matthew D. AU - Gannon, Travis W. AU - Brosnan, James T. AU - Breeden, Gregory K. T2 - WEED TECHNOLOGY AB - Indaziflam is a PRE herbicide for annual broadleaf and grass control in turfgrass systems and requires a 40-wk minimum interval between application and overseeding perennial ryegrass. Currently, activated-charcoal application is recommended to reduce that interval; however, preliminary evaluations determined activated charcoal alone was not a robust mitigation practice for successful establishment during perennial ryegrass overseeding. Field research was conducted in North Carolina and Tennessee to evaluate various mitigation practices to effectively overseed perennial ryegrass into indaziflam-treated turfgrass areas. Immediately following indaziflam application (53 g ai ha −1 ), two scenarios were created by delivering 0 or 0.3 cm H 2 O before mitigation practice. Irrigated plots were air-dried before conducting mitigation practices. Evaluated mitigation practices included scalping (0.6 cm cut height; debris removed), verticutting (1.25 cm depth; debris removed), and activated-charcoal application (167 kg ha −1 applied as an aqueous slurry in 3,180 L ha −1 ), evaluated individually and in each two-way combination in the order scalp followed by (fb) activated charcoal, scalp fb verticut, or verticut fb activated charcoal. Twenty-four hours after mitigation practice completion, perennial ryegrass was seeded (976 kg ha −1 ) and maintained as a golf course fairway. Overall, perennial ryegrass cover was reduced ≥ 93% at 8 and 20 wk after treatment (WAT) when no mitigation practices were performed. Stand-alone mitigation practices variably improved perennial ryegrass establishment; however, no practice provided acceptable results for end users. Combining mitigation practices improved overseeding establishment, most notably by adding activated charcoal application or verticutting to scalping before irrigation. Across experimental runs and locations, scalp fb activated-charcoal application before irrigation reduced perennial ryegrass cover 22 to 27% at 20 WAT. Results from this research suggest mitigation practices in addition to the currently recommended activated-charcoal application should be performed by turfgrass managers to improve perennial ryegrass overseeding establishment in indaziflam-treated turfgrass areas. DA - 2016/// PY - 2016/// DO - 10.1614/wt-d-15-00069.1 VL - 30 IS - 1 SP - 154-162 SN - 1550-2740 KW - Activated charcoal KW - best management practice KW - pesticide remediation KW - scalp KW - verticut ER - TY - JOUR TI - Importance of Limestone Specific Surface for Assessing Neutralization Effectiveness in Soilless Root Substrate AU - Rippy, Janet F. M. AU - Nelson, Paul V. AU - Hesterberg, Dean L. AU - Niedziela, Carl E., Jr. AU - Kamprath, Eugene J. AU - Bilderback, Ted T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - The relationship of specific surface to particle diameter and calcium carbonate (CaCO3) content of limestone was examined. Limestones obtained from 20 North American quarries were wet sieved into eight particle diameter fractions (600 to ˂38 µm). Specific surface of particles was measured in each fraction following the Brunauer-Emmett-Teller theory. The range in specific surface across the 20 sources varied from 74-fold in the coarsest particles (600–300 µm) to 20-fold in the finest particles (˂38 µm). The pattern of specific surface progressing from the coarsest to the finest particles varied radically between sources. The relationship between specific surface and CaCO3 content was likewise very weak. While particle diameter and CaCO3 equivalent remain the traditional measurements for defining limestone for field production, specific surface provides additional information valuable to define the stricter neutralization capacities of limestone for soilless root substrates. DA - 2016/2/21/ PY - 2016/2/21/ DO - 10.1080/00103624.2016.1141926 VL - 47 IS - 4 SP - 521-526 SN - 1532-2416 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84961212516&partnerID=MN8TOARS KW - Calcium carbonate KW - liming KW - magnesium carbonate KW - pH ER - TY - JOUR TI - Factors Influencing Dislodgeable 2, 4-D Plant Residues from Hybrid Bermudagrass (Cynodon dactylon L. x C. transvaalensis) Athletic Fields AU - Jeffries, Matthew D. AU - Gannon, Travis W. AU - Brosnan, James T. AU - Ahmed, Khalied A. AU - Breeden, Gregory K. T2 - PLOS ONE AB - Research to date has confirmed 2,4-D residues may dislodge from turfgrass; however, experiments have not been conducted on hybrid bermudagrass (Cynodon dactylon L. x C. transvaalensis), the most common athletic field turfgrass in subtropical climates. More specifically, previous research has not investigated the effect of post-application irrigation on dislodgeable 2,4-D residues from hybrid bermudagrass and across turfgrass species, research has been nondescript regarding sample time within a d (TWD) or conducted in the afternoon when the turfgrass canopy is dry, possibly underestimating potential for dislodgement. The effect of irrigation and TWD on 2,4-D dislodgeability was investigated. Dislodgeable 2,4-D amine was reduced > 300% following irrigation. From 2 to 7 d after treatment (DAT), ≤ 0.5% of applied 2,4-D was dislodged from irrigated turfgrass, while ≤ 2.3% of applied 2,4-D was dislodged when not irrigated. 2,4-D dislodgeability decreased as TWD increased. Dislodgeable 2,4-D residues declined to < 0.1% of the applied at 1 DAT– 13:00, and increased to 1 to 3% of the applied 2 DAT– 5:00, suggesting 2,4-D re-suspended on treated turfgrass vegetation overnight. In conclusion, irrigating treated turfgrass reduced dislodgeable 2,4-D. 2,4-D dislodgeability increased as TWD decreased, which was attributed to non-precipitation climatic conditions favoring turfgrass canopy wetness. This research will improve turfgrass management practices and research designed to minimize human 2,4-D exposure. DA - 2016/2/10/ PY - 2016/2/10/ DO - 10.1371/journal.pone.0148992 VL - 11 IS - 2 SP - SN - 1932-6203 ER - TY - JOUR TI - Environmental Influences on Growth and Reproduction of Invasive Commelina benghalensis AU - Riar, Mandeep K. AU - Carley, Danesha S. AU - Zhang, Chenxi AU - Schroeder-Moreno, Michelle S. AU - Jordan, David L. AU - Webster, Theodore M. AU - Rufty, Thomas W. T2 - International Journal of Agronomy AB - Commelina benghalensis (Benghal dayflower) is a noxious weed that is invading agricultural systems in the southeastern United States. We investigated the influences of nutrition, light, and photoperiod on growth and reproductive output of C. benghalensis . In the first experimental series, plants were grown under high or low soil nutrition combined with either full light or simulated shade. Lowered nutrition strongly inhibited vegetative growth and aboveground spathe production. Similar but smaller effects were exerted by a 50% reduction in light, simulating conditions within a developing canopy. In the second series of experiments, C. benghalensis plants were exposed to different photoperiod conditions that produced short- and long-day plants growing in similar photosynthetic periods. A short-day photoperiod decreased time to flowering by several days and led to a 40 to 60% reduction in vegetative growth, but reproduction above and below ground was unchanged. Collectively, the results indicate that (1) fertility management in highly weathered soils may strongly constrain competitiveness of C. benghalensis ; (2) shorter photoperiods will limit vegetative competitiveness later in the growing seasons of most crops; and (3) the high degree of reproductive plasticity and output possessed by C. benghalensis will likely cause continual persistence problems in agricultural fields. DA - 2016/// PY - 2016/// DO - 10.1155/2016/5679249 VL - 2016 SP - 1–9 SN - 1687-8159 1687-8167 UR - http://dx.doi.org/10.1155/2016/5679249 ER - TY - JOUR TI - A cell wall-bound anionic peroxidase, PtrPO21, is involved in lignin polymerization in Populus trichocarpa AU - Lin, Chien-Yuan AU - Li, Quanzi AU - Tunlaya-Anukit, Sermsawat AU - Shi, Rui AU - Sun, Ying-Hsuan AU - Wang, Jack P. AU - Liu, Jie AU - Loziuk, Philip AU - Edmunds, Charles W. AU - Miller, Zachary D. AU - Peszlen, Ilona AU - Muddiman, David C. AU - Sederoff, Ronald R. AU - Chiang, Vincent L. T2 - TREE GENETICS & GENOMES DA - 2016/4// PY - 2016/4// DO - 10.1007/s11295-016-0978-y VL - 12 IS - 2 SP - SN - 1614-2950 KW - Lignin polymerization KW - Populus trichocarpa KW - Lignin peroxidase KW - LC-MS/MS KW - Lignin systems biology ER - TY - JOUR TI - A Structural Study of CESA1 Catalytic Domain of Arabidopsis Cellulose Synthesis Complex: Evidence for CESA Trimers AU - Vandavasi, Venu Gopal AU - Putnam, Daniel K. AU - Zhang, Qiu AU - Petridis, Loukas AU - Heller, William T. AU - Nixon, B. Tracy AU - Haigler, Candace H. AU - Kalluri, Udaya AU - Coates, Leighton AU - Langan, Paul AU - Smith, Jeremy C. AU - Meiler, Jens AU - O’Neill, Hugh T2 - Plant Physiology AB - A cellulose synthesis complex with a "rosette" shape is responsible for synthesis of cellulose chains and their assembly into microfibrils within the cell walls of land plants and their charophyte algal progenitors. The number of cellulose synthase proteins in this large multisubunit transmembrane protein complex and the number of cellulose chains in a microfibril have been debated for many years. This work reports a low resolution structure of the catalytic domain of CESA1 from Arabidopsis (Arabidopsis thaliana; AtCESA1CatD) determined by small-angle scattering techniques and provides the first experimental evidence for the self-assembly of CESA into a stable trimer in solution. The catalytic domain was overexpressed in Escherichia coli, and using a two-step procedure, it was possible to isolate monomeric and trimeric forms of AtCESA1CatD. The conformation of monomeric and trimeric AtCESA1CatD proteins were studied using small-angle neutron scattering and small-angle x-ray scattering. A series of AtCESA1CatD trimer computational models were compared with the small-angle x-ray scattering trimer profile to explore the possible arrangement of the monomers in the trimers. Several candidate trimers were identified with monomers oriented such that the newly synthesized cellulose chains project toward the cell membrane. In these models, the class-specific region is found at the periphery of the complex, and the plant-conserved region forms the base of the trimer. This study strongly supports the "hexamer of trimers" model for the rosette cellulose synthesis complex that synthesizes an 18-chain cellulose microfibril as its fundamental product. DA - 2016/1// PY - 2016/1// DO - 10.1104/pp.15.01356 VL - 170 IS - 1 SP - 123–135 SN - 0032-0889 1532-2548 UR - http://dx.doi.org/10.1104/pp.15.01356 ER - TY - JOUR TI - Using an Arrhenius-type function to describe temperature response of plant developmental processes: inference and cautions AU - Michelangeli, Jose A. Clavijo AU - Sinclair, Thomas R. AU - Bliznyuk, Nikolay T2 - NEW PHYTOLOGIST AB - Managing the impacts of weather on agricultural systems requires developing practices and novel germplasm capable of withstanding erratic temperature regimes, which will be critical under projected global climate change scenarios (Lobell et al., 2008). Thus, describing temperature responses of developmental and growth processes, and identifying the underlying genetic signal has long been a key challenge in plant biology. In this letter, we review the approach used to describe temperature responses presented by Parent & Tardieu (2012) using a modified nonlinear function originally developed to study enzyme kinetics. Three specific issues are addressed in this letter. (1) Does the function offer mechanistic insight? (2) Are there clear statistical criteria for function evaluation? (3) Does the function appropriately relate to observed genetic variation in temperature response? Using Eqn 2, Parent & Tardieu (2012) specifically tested two hypotheses: (1) genotypes of the species originating from ‘cold or warm’ areas (e.g. maize lines from temperate or tropical regions) have different temperature responses, via the analysis of fitted parameters of a nonlinear function (derivation discussed later); and (2) one or more of the solved parameters of the function used were similar within or across species. The test of shape of the response curves were studied using normalized rates (referenced to 20°C) of growth (tissue expansion and cell division) and development (germination, node addition, time to anthesis) from novel and previously published experiments using several genotypes of wheat (Triticum aestivum), maize (Zea mays), rice (Oryza spp.) and barley (Hordeum vulgare) and an additional 14 species via a meta-analysis. An initial concern is the interpretation of the parameters resulting from fitting Eqn 2 to experimental data. For instance, according to Parent & Tardieu (2012) the parameter α is actually the /ratio in Eqn 1. Hence, when fitting α separately in Eqn 2, the original dependency of the ratio on is lost, affecting the estimation process and the claimed inferences. Consequently, regression fits of Eqn 2 essentially become empirical descriptions of the experimental data. While the use of empirical functions to study the genetic control of different growth and developmental processes is well established, it seems unjustified to suggest that the empirical structure of Eqn 2 provides insight about an ‘immutable law with parameters based on physical constraints’ in plant temperature response. Therefore, we conclude that Eqn 2 is essentially another possibility for describing plant responses to temperature without being able to claim any particular insight about the basic nature of the processes influencing temperature sensitivity. As suggested by Price et al. (2012), a model must first be logically consistent, and second, provide biologically useful or meaningful insight. As discussed earlier, use of Boltzmann–Arrhenius functions derived for individual enzymatic reactions can only be considered approximations of temperature sensitivity of whole-organism metabolic rates, and may well miss representing key processes involved in temperature response (Price et al., 2012). This problem seems especially challenging in a plant breeding context, where identifying and using specific phenotypic targets in selection schemes would be critical in improving a complex trait such as developmental rate or organ temperature responses. Ambiguity about the derived parameters for Eqn 2 seems to preclude the possibility of gaining insights about genetic variability. This ambiguity is highlighted by the fact that Parent & Tardieu (2012) offered eight alternative approaches (Table 1) to solve the three parameters in Eqn 2. These approaches considered all possible combinations in determining the parameters of Eqn 2 (, T0 and α) by either solving all parameters (referred to as being ‘free’) or by fixing up to two parameters (i.e. ‘fixed’) and solving the rest in the regression analysis. Table 1 gives the identifications of the three approaches in comparison with genotype or species, or between and across species, depending on the data set. Critically, details of the data pooling procedures from the different temperature experiments were not readily available in Parent & Tardieu (2012), making assessments of the fitting procedures difficult since the datasets used varied widely in scope, experimental conditions, measured traits and sample sizes. Furthermore, the eight approaches in evaluating Eqn 2 were not all fitted by using the same optimization procedures, and relied on assumptions that may well not have been met. More formally, numerical issues aside, the objective functions presented in their Supporting Information Fig. S3 (p. 5) for the three models are equivalent to Gaussian maximum likelihood objective functions (with independent errors) only under the strong assumption of equal variances across all lines and temperature treatments. This assumption was not stated, let alone justified, in the manuscript. This can be problematic, since failure to account for variance heterogeneity or observation independence can lead to inaccurate parameter estimates and/or distorted standard errors (Ritz & Streibig, 2008), and affect criteria for model selection (Burnham & Anderson, 2002). Packages or routines exist in all major statistical software to accurately model these scenarios (e.g. gnls package in R, proc nlin in SAS®). The analysis of the model selection approach used by Parent & Tardieu (2012) also raises concerns, particularly in terms of the model selected as best, and those that are discarded. In each analysis scenario, the fitted models were ranked based on the Bayesian Information Criterion (BIC), while Akaike's Information Criterion (AIC) was also provided. Both measures are based on minimizing the Kullback–Leibler divergence (i.e. the amount of information lost when using a model to approximate reality), but the derivations and interpretations of the two statistics differ (Burnham & Anderson, 2002). For both cases, models are penalized depending on the number of parameters, and the best model within the subset is that with the smallest criterion value. Since several models may have similar information criteria values, an established selection approach is based on the differences in information criteria values between the best (i.e. lowest AIC or BIC value) model, and the rest (denoted as ΔAIC or ΔBIC). For this purpose, Burnham & Anderson (2002) proposed a widely-used rule of thumb where models approximately 2 AIC or BIC units from the best model have substantial empirical support, those within 4–7 units considerably less, while models > 10 units away have essentially no support. Furthermore, the ΔAIC or ΔBIC values are also used to compute weights (denoted as wAIC or wBIC), which are interpreted as the relative likelihood that each model (normalized to sum to one) is the expected best model among those tested (Burnham & Anderson, 2002). However, the statistical model and approach used to calculate the likelihoods and information criteria in Parent & Tardieu (2012) was not stated explicitly. With these guidelines and comments in mind, results in Supporting Information Table S1 of Parent & Tardieu (2012) indicated that models with parameters estimated by genotype cannot be discarded for maize, rice and wheat. Specifically, for maize and rice, none of the model fits are farther apart than 3.2 BIC units from each other, suggesting none of them should be discarded outright for making inferences about genotypic differences. In addition, the best models for both maize and rice are not those where parameters are estimated across all genotypes (model M.0), but instead M.1a (with wBIC of 0.27 and 0.21, respectively), which has T0 estimated by genotype, and the remaining parameter across genotypes. Although for wheat the best model is in fact M.0, it is < 0.5 BIC units from model M.1a, and consequently, the latter should also be considered a strong candidate model. Supposing that the model interpretations and fitting procedures raised were addressed, the model selection procedures used should lead to more cautious conclusions than those presented in Parent & Tardieu (2012). The results seem to indicate that, in all likelihood, the temperature response of developmental processes is not the same for all genotypes within each crop species in individual crop experiment datasets (i.e. the fits of genotypes of maize, rice and wheat). Thus, the overall conclusion that breeding has not changed the temperature responses within these crops cannot be supported given the data utilized. For the comparison of maize, rice, wheat and A. thaliana (their Table S1, bottom), a more appropriate interpretation would indicate that model M.2b is the most likely model within those tested, while models M.1a, M.2c, M.2a and M.3 cannot be discarded. In this case, while the original overall conclusions of Parent & Tardieu (2012) would stand, the identification of the parameters under genetic control and the uncertainty around their estimates are more tenuous than those provided. Moreover, many peer-reviewed publications have identified genetic variability for the temperature responses of various processes within the ranges studied in Parent & Tardieu (2012) in maize (e.g. Pešev, 1970; Eagles & Hardacre, 1979; Maryam & Jones, 1983; Dolstra et al., 1994), wheat (Cao & Moss, 1989; Slafer & Rawson, 1995; Robertson et al., 1996) and rice (Glaszmann et al., 1990; Yin & Kropff, 1996; Yin et al., 1996; Fujino et al., 2004; Jiang et al., 2008; Suh et al., 2010; Lin et al., 2014), including studies in molecular biology, whole-plant physiology and modeling. Taken as a whole, the large body of evidence suggesting genetic control of temperature responses should at least be considered when making conclusions regarding the effects of evolution or selection on current crop responses. The authors thank Martijn Slot for helpful comments that improved the final version of the paper. DA - 2016/4// PY - 2016/4// DO - 10.1111/nph.13812 VL - 210 IS - 2 SP - 377-379 SN - 1469-8137 KW - Arrhenius equation KW - genetic variability KW - phenology KW - plant development KW - temperature response ER - TY - JOUR TI - The genome sequences of Arachis duranensis and Arachis ipaensis, the diploid ancestors of cultivated peanut AU - Bertioli, David John AU - Cannon, Steven B. AU - Froenicke, Lutz AU - Huang, Guodong AU - Farmer, Andrew D. AU - Cannon, Ethalinda K. S. AU - Liu, Xin AU - Gao, Dongying AU - Clevenger, Josh AU - Dash, Sudhansu AU - Ren, Longhui AU - Moretzsohn, Marcio C. AU - Shirasawa, Kenta AU - Huang, Wei AU - Vidigal, Bruna AU - Abernathy, Brian AU - Chu, Ye AU - Niederhuth, Chad E. AU - Umale, Pooja AU - Araujo, Ana Claudia G. AU - Kozik, Alexander AU - Do Kim, Kyung AU - Burow, Mark D. AU - Varshney, Rajeev K. AU - Wang, Xingjun AU - Zhang, Xinyou AU - Barkley, Noelle AU - Guimaraes, Patricia M. AU - Isobe, Sachiko AU - Guo, Baozhu AU - Liao, Boshou AU - Stalker, H. Thomas AU - Schmitz, Robert J. AU - Scheffler, Brian E. AU - Leal-Bertioli, Soraya C. M. AU - Xun, Xu AU - Jackson, Scott A. AU - Michelmore, Richard AU - Ozias-Akins, Peggy T2 - NATURE GENETICS AB - Cultivated peanut (Arachis hypogaea) is an allotetraploid with closely related subgenomes of a total size of ∼2.7 Gb. This makes the assembly of chromosomal pseudomolecules very challenging. As a foundation to understanding the genome of cultivated peanut, we report the genome sequences of its diploid ancestors (Arachis duranensis and Arachis ipaensis). We show that these genomes are similar to cultivated peanut's A and B subgenomes and use them to identify candidate disease resistance genes, to guide tetraploid transcript assemblies and to detect genetic exchange between cultivated peanut's subgenomes. On the basis of remarkably high DNA identity of the A. ipaensis genome and the B subgenome of cultivated peanut and biogeographic evidence, we conclude that A. ipaensis may be a direct descendant of the same population that contributed the B subgenome to cultivated peanut. DA - 2016/4// PY - 2016/4// DO - 10.1038/ng.3517 VL - 48 IS - 4 SP - 438-+ SN - 1546-1718 ER - TY - JOUR TI - Sidedress Nitrogen Application Rates to Sorghum lntercropped with Tropical Perennial Grasses AU - Mateus, G. P. AU - Crusciol, C. A. C. AU - Pariz, C. M. AU - Borghi, E. AU - Costa, C. AU - Martello, J. M. AU - Franzluebbers, A. J. AU - Castilhos, A. M. T2 - AGRONOMY JOURNAL AB - Intercropping sorghum [ Sorghum bicolor (L.) Moench] with tropical perennial grasses and using the appropriate rate of sidedress N application can maximize grain yield (GY) and revenue and can improve land‐use efficiency (LUE). The effects of monocropped sorghum (MS) or sorghum intercropped with palisadegrass ( Urochloa brizantha cv. Marandu; SPG) or guineagrass ( Panicum maximum cv. Mombaça; SGG) and sidedress N application rates of 0, 50, 100, and 200 kg ha −1 on leaf nutrient concentration, sorghum GY, revenue, and LUE were investigated during three growing seasons at Botucatu, SP, Brazil, on a clay, kaolinitic, thermic Typic Haplorthox. The SGG treatment had lower leaf N, P, and K concentrations and lower 1000‐grain weight, shoot dry matter, and GY than MS and SPG at all sidedress N rates; MS and SPG at 200 kg ha −1 of sidedress N resulted in greater sorghum GYs (3.80 and 3.81 Mg ha −1 , respectively). The forage dry matter production (FDMP) and crude protein of tropical perennial grasses were higher as a function of the sidedress N rate. The SGG treatment resulted in negative net profits for all sidedress N rates. The MS and SPG treatments (independent of sidedress N rates) resulted in similar net profits (approximately US$85 and $60 ha −1 , respectively). The SPG treatment using 200 kg ha −1 of sidedress N resulted in a higher land equivalent ratio and relative N yield (1.27 and 123%, respectively) than SGG (0.96 and 107%, respectively). The SPG treatment with 200 kg ha −1 of sidedress N is the best option for increasing sorghum GY, revenue, and FDMP from autumn to part of the spring and for improving LUE. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2015.0236 VL - 108 IS - 1 SP - 433-447 SN - 1435-0645 ER - TY - JOUR TI - Prediction of the structures of the plant-specific regions of vascular plant cellulose synthases and correlated functional analysis AU - Sethaphong, Latsavongsakda AU - Davis, Jonathan K. AU - Slabaugh, Erin AU - Singh, Abhishek AU - Haigler, Candace H. AU - Yingling, Yaroslava G. T2 - Cellulose DA - 2016/2// PY - 2016/2// DO - 10.1007/s10570-015-0789-6 VL - 23 IS - 1 SP - 145–161 SN - 0969-0239 1572-882X UR - http://dx.doi.org/10.1007/s10570-015-0789-6 KW - Arabidopsis thaliana KW - Cellulose synthesis KW - Computational protein structure prediction KW - Isoform specificity KW - Mutant complementation ER - TY - JOUR TI - Planting Date Impacts on Soil Water Management, Plant Growth, and Weeds in Cover-Crop-Based No-Till Corn Production AU - Wells, M. Scott AU - Reberg-Horton, S. Chris AU - Mirsky, Steven B. T2 - AGRONOMY JOURNAL AB - Low input and organic farmers are utilizing cover crop mulches in corn ( Zea mays L.) production. Corn planting is typically delayed to improve the efficacy of mechanical termination with roller‐crimpers. During the late spring, as cover crops are allowed to grow to maximize biomass production, soil moisture reserves can become depleted, thereby directly impacting early season growth of the subsequent cash crop. A 4 site‐year study was conducted in North Carolina (Goldsboro, Kinston, and Salisbury) to evaluate the effects of timing of corn planting after roller‐crimping a cover crop mulch, on soil moisture, crop stand, weed pressure and corn yield. Two cover crop mixtures were compared: winter pea [P/R, Pisum sativum ssp. arvense (L.) Poir.], and hairy vetch (HV/R, Vicia villosa Roth) were both mixed with cereal rye (Secale cereale L.). Both cover crop treatments produced biomass greater than 7000 kg ha −1 dry matter at all sites. Delayed planting after the cover crops were rolled‐crimped did not enhance the soil volumetric water content (VWC) within the upper 10 cm. However, at Kinston in 2012, the VWC was 23% greater in the HV/R when compared to P/R and no‐mulch treatments. The corn planting date across all 4 site‐years did not affect weed biomass. Corn (2011) in the cover crop treatments yielded equivalent to their weed‐free no‐till without cover crop mulch counterparts. These results support the viability of rolled‐crimped cover crop mulches as a lower energy input alternative to existing organic corn systems that rely solely on intensive tillage for weed management. DA - 2016/// PY - 2016/// DO - 10.2134/agronj2014.0524 VL - 108 IS - 1 SP - 162-170 SN - 1435-0645 ER - TY - JOUR TI - Novel QTL associated with the Fusarium head blight resistance in Truman soft red winter wheat AU - Islam, Md. Sariful AU - Brown-Guedira, Gina AU - Van Sanford, David AU - Ohm, Herb AU - Dong, Yanhong AU - McKendry, Anne L. T2 - EUPHYTICA DA - 2016/2// PY - 2016/2// DO - 10.1007/s10681-015-1550-9 VL - 207 IS - 3 SP - 571-592 SN - 1573-5060 KW - QTL KW - Wheat KW - FHB KW - Truman ER - TY - JOUR TI - Limited transpiration under high vapor pressure deficits of creeping bentgrass by application of Daconil-Action (R) AU - Shekoofa, Avat AU - Rosas-Anderson, Pablo AU - Carley, Danesha S. AU - Sinclair, Thomas R. AU - Rufty, Thomas W. T2 - PLANTA DA - 2016/2// PY - 2016/2// DO - 10.1007/s00425-015-2417-y VL - 243 IS - 2 SP - 421-427 SN - 1432-2048 KW - Daconil action KW - Creeping bentgrass KW - Transpiration rate KW - Vapor pressure deficit KW - Water conservation ER - TY - JOUR TI - Leaf aquaporin transcript abundance in peanut genotypes diverging in expression of the limited-transpiration trait when subjected to differing vapor pressure deficits and aquaporin inhibitors AU - Devi, M. Jyostna AU - Sinclair, Thomas R. AU - Jain, Mukesh AU - Gallo, Maria T2 - PHYSIOLOGIA PLANTARUM AB - A plant trait currently being exploited to decrease crop yield loss under water-deficit conditions is limited-transpiration rate (TRlim ) under high atmospheric vapor pressure deficit (VPD) conditions. Although limited genotype comparisons for the TRlim trait have been performed in peanut (Arachis hypogaea), no detailed study to describe the basis for this trait in peanut has been reported. Since it has been hypothesized that the TRlim trait may be a result of low leaf hydraulic conductance associated with aquaporins (AQPs), the first objective of this study was to examine a possible correlation of TRlim to leaf AQP transcriptional profiles in six peanut cultivars. Five of the studied cultivars were selected because they expressed TRlim while the cultivar York did not. Transcripts of six AQPs were measured. Under exposure to high vapor pressure deficit, cultivar C 76-16 had decreased AQP transcript abundance for four of the six AQPs but in York only one AQP had decreased abundance. The second objective was to explore the influence of AQP inhibitors mercury and silver on expression of TRlim and AQP transcription profiles. Quantitative RT-PCR data were compared in cultivars York and C 76-16, which had the extreme response in TR to VPD. Inhibitor treatment resulted in increased abundance of AQP transcripts in both. The results of these experiments indicate that AQP transcript abundance itself may not be useful in identifying genotypes expressing the TRlim trait under high VPD conditions. DA - 2016/4// PY - 2016/4// DO - 10.1111/ppl.12378 VL - 156 IS - 4 SP - 387-396 SN - 1399-3054 ER - TY - JOUR TI - Layer plate CAS assay for the quantitation of siderophore production and determination of exudation patterns for fungi AU - Andrews, Megan Y. AU - Santelli, Cara M. AU - Duckworth, Owen W. T2 - JOURNAL OF MICROBIOLOGICAL METHODS AB - The chrome azurol S (CAS) assay measures the chelating activity of siderophores, but its application (especially to fungi) is limited by toxicity issues. In this note, we describe a modified version of the CAS assay that is suitable for quantifying siderophore exudation for microorganisms, including fungi. DA - 2016/2// PY - 2016/2// DO - 10.1016/j.mimet.2015.12.012 VL - 121 SP - 41-43 SN - 1872-8359 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84953386448&partnerID=MN8TOARS KW - Siderophores KW - CAS assay KW - Quantitative assay KW - Fungi ER - TY - JOUR TI - Energy and evapotranspiration partitioning in a desert vineyard AU - Kool, D. AU - Kustas, W. P. AU - Ben-Gal, A. AU - Lazarovitch, N. AU - Heitman, J. L. AU - Sauer, T. J. AU - Agam, N. T2 - AGRICULTURAL AND FOREST METEOROLOGY AB - The challenge of partitioning energy and evapotranspiration (ET) components was addressed over a season (bud break till harvest) in a wine grape vineyard located in an extreme arid region. A below canopy energy balance approach was applied to continuously estimate evaporation from the soil (E) while system ET was measured using eddy covariance. Below canopy energy balance was assessed at the dry midrow position as well as the wet irrigated position directly underneath the vine row, with E calculated as the residual of measured net radiation, soil heat flux, and computed sensible heat flux. The variables used to compute sensible heat flux included soil surface temperature measured using infrared thermometers and below-canopy wind speed in a soil resistance formulation that required a modified wind factor. The E derived from below canopy energy balance was reasonable at daily intervals although it underestimated micro-lysimeter E measurements, suggesting there may have been advected energy from the midrow to the below-vine position. Seasonal partitioning indicated that total E amounted to 9–11% of ET. In addition, empirical functions from the literature relating crop coefficients (Kcb) to plant size, appeared to give reasonable results under full canopy, albeit with some day to day variation, but underestimated Kcb during the growing period. DA - 2016/3/15/ PY - 2016/3/15/ DO - 10.1016/j.agrformet.2016.01.002 VL - 218 SP - 277-287 SN - 1873-2240 KW - Evaporation KW - Transpiration KW - Latent heat KW - Sparse canopy KW - Water use efficiency KW - Energy balance KW - Water balance KW - Crop coefficient ER - TY - JOUR TI - Differences between wheat genotypes in damage from freezing temperatures during reproductive growth AU - Livingston, David P., III AU - Tuong, Tan D. AU - Isleib, Thomas G. AU - Murphy, J. Paul T2 - EUROPEAN JOURNAL OF AGRONOMY AB - Cereal crops in the reproductive stage of growth are considerably more susceptible to injury from freezing temperatures than during their vegetative growth stage in the fall. While damage resulting from spring-freeze events has been documented, information on genotypic differences in tolerance to spring-freezes is scarce. Ninety wheat genotypes were subjected to a simulated spring-freeze at the mid-boot growth stage under controlled conditions. Spring-freeze tolerance was evaluated as the number of seeds per head at maturity after plants were frozen at −6 °C. Plants that froze, as confirmed by infrared (IR) thermography, died shortly after thawing and consequently the heads did not mature. Only in plants that had no visible freezing (super-cooled) were heads able to reach maturity and produce seeds. In plants that super-cooled four genotypes had significantly higher seed counts after being exposed to freezing than three with the lowest. In addition, significant differences between genotypes were found in whole plant survival among those that had frozen. Genotypes with high whole-plant freezing survival were not necessarily the same as the super-cooled plants with the highest seed counts. Spring-freeze tolerance was not correlated with maturity suggesting that improvement in freezing tolerance could be selected for without affecting heading date. Spring-freeze tolerance was not correlated with freezing tolerance of genotypes of plants in a vegetative state, either under non-acclimated or cold-acclimated conditions indicating that vegetative freezing tolerance is not a good predictor of spring-freeze tolerance. DA - 2016/3// PY - 2016/3// DO - 10.1016/j.eja.2015.12.002 VL - 74 SP - 164-172 SN - 1873-7331 KW - Wheat KW - Spring freeze KW - Heading KW - Infra red thermography KW - Supercooling KW - Barrier ER - TY - JOUR TI - Control of brown patch (Rhizoctonia solani) in tall fescue (Festuca arundinacea Schreb.) by host induced gene silencing AU - Zhou, Binbin AU - Bailey, Ana AU - Niblett, C. L. AU - Qu, Rongda T2 - PLANT CELL REPORTS DA - 2016/4// PY - 2016/4// DO - 10.1007/s00299-015-1921-7 VL - 35 IS - 4 SP - 791-802 SN - 1432-203X KW - Brown patch KW - Disease resistance KW - HIGS KW - Rhizoctonia solani KW - RNAi KW - Tall fescue ER - TY - JOUR TI - Phytotoxicity and Benzoxazinone Concentration in Field Grown Cereal Rye (Secale cereale L.) AU - La Hovary, C. AU - Danehower, D. A. AU - Ma, G. AU - Reberg-Horton, C. AU - Williamson, J. D. AU - Baerson, S. R. AU - Burton, J. D. T2 - International Journal of Agronomy AB - Winter rye ( Secale cereale L.) is used as a cover crop because of the weed suppression potential of its mulch. To gain insight into the more effective use of rye as a cover crop we assessed changes in benzoxazinone (BX) levels in rye shoot tissue over the growing season. Four rye varieties were planted in the fall and samples harvested at intervals the following spring. Two different measures of phytotoxic compound content were taken. Seed germination bioassays were used as an estimate of total phytotoxic potential. Dilutions of shoot extracts were tested using two indicator species to compare the relative toxicity of tissue. In addition, BX (DIBOA, DIBOA-glycoside, and BOA) levels were directly determined using gas chromatography. Results showed that rye tissue harvested in March was the most toxic to indicator species, with toxicity decreasing thereafter. Likewise the BX concentration in rye shoot tissue increased early in the season and then decreased over time. Thus, phytotoxicity measured by bioassay and BX levels measured by GC have a similar but not identical temporal profile. The observed decrease in phytotoxic potential and plant BX levels in rye later in the season appears to correlate with the transition from vegetative to reproductive growth. DA - 2016/// PY - 2016/// DO - 10.1155/2016/6463826 VL - 2016 SP - LA - en SN - 1687-8167 UR - https://www.hindawi.com/journals/ija/2016/6463826/ Y2 - 2019/2/12/ ER -