TY - JOUR TI - Microbial phosphorus fluctuation in a hapludalf under natural pasture, with cut off and forage species introduction, fertilized in different times,Amplitude no fósforo microbiano em um argissolo em pastagem nativa submetida à roçada e à introdução de espécies forrageiras com fertilização fosfatada em diferentes épocas AU - Santos Rheinheimer, D. AU - Martinazzo, R. AU - Gatiboni, L.C. AU - Kaminski, J. AU - Silva, L.S. T2 - Acta Scientiarum - Agronomy AB - In very weathered soils, the temporary phosphorus immobilization by soil microbial biomass (SMB) could be a mechanism to reduce P adsorption. This study was carried out to evaluate the microbial phosphorus (Pm) content fluctuation in a Hapludalf under natural pasture with cut off and exotic forage species introduction and fertilized with phosphorus fertilizers. The experiment was conducted in 1997 with five treatments: control without P, natural gafsa phosphate, triple superphosphate, triple superphosphate + lime, and single superphosphate + lime. In 2002, natural pasture was cut off and a mix of ryegrass and arrowleaf clover was planted in a no-tillage system. The original plots were split into three sub-plots: without P reapplication; P reapplication after cut off in winter, and P reapplication after cut off in spring. The first Pm evaluation was made 16 days before the first cut off, considered the beginning of the experiment (day 0). Soil samples for Pm evaluation were taken at 0, 25, 36, 55, 82, 111, 139, 163, 171, 181, 197, 219, 229, 248, 274, and 316 days after the beginning of the experiment. The cut off stimulated Pm immobilization by microbial biomass. Part of the phosphorus from fertilizers was temporary immobilized by microbial biomass. DA - 2008/// PY - 2008/// DO - 10.4025/actasciagron.v30i4.5319 VL - 30 IS - 4 SP - 561-567 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-72749104782&partnerID=MN8TOARS ER - TY - JOUR TI - Factors affecting the phosphorus availability and the fertilization management in no-tillage system,Fatores que afetam a disponibilidade do fósforo e o manejo da adubação fosfatada em solos sob sistema plantio direto AU - Dos Santos, D.R. AU - Gatiboni, L.C. AU - Kaminski, J. T2 - Ciencia Rural AB - A compreensão dos fenômenos básicos da dinâmica do fósforo no solo é importante para a tomada de decisão sobre a necessidade de adição e para a definição das doses e dos modos de aplicação de fertilizantes fosfatados. As formas e o grau de labilidade do fósforo variam com as características e propriedades do solo. Em solos jovens, os fosfatos de cálcio são os principais fornecedores de fósforo aos organismos vivos. Por outro lado, em solos altamente intemperizados, a biociclagem dos fosfatos orgânicos assume grande importância na manutenção da biodisponibilidade, embora não seja suficiente para a obtenção da máxima produtividade econômica das culturas comerciais. Nos solos tropicais e subtropicais cultivados, o controle dos teores de fósforo em solução é feito predominantemente pelo fosfato adsorvido aos grupos funcionais dos colóides inorgânicos. O diagnóstico da disponibilidade de fósforo é feito pela análise de solos por diferentes metodologias, cada uma com suas vantagens e limitações. A tomada de decisão em adicionar ou não fosfatos ao solo e a definição da dose a ser aplicada dependem muito mais da calibração, baseada na relação entre os teores de fósforo extraídos e a produtividade das plantas, do que do método de extração. A elevação dos níveis de disponibilidade de fósforo até a faixa ótima pode ser feita de forma corretiva ou gradativa. A adubação corretiva com incorporação em todo o volume de solo é mais eficiente e, talvez, a única alternativa para a correção da carência de fósforo do solo das camadas subsuperficias. A aplicação superficial de fertilizantes fosfatados no sistema plantio direto parece não ser uma boa alternativa econômica e pode se tornar um problema ambiental. Desse modo, devem-se intensificar as pesquisas enfocando, entre outras: (a) as frações de fósforo no solo e a produtividade das culturas; (b) as formas de aplicação dos fertilizantes fosfatados no solo sob sistema plantio direto; (c) as relações entre a disponibilidade de fósforo nas camadas subsuperficiais (abaixo de 10cm), a presença de alumínio trocável e de camadas compactadas e (d) o monitoramento constante das transferências de fósforo dos solos aos sistemas aquáticos. DA - 2008/// PY - 2008/// DO - 10.1590/S0103-84782008000200049 VL - 38 IS - 2 SP - 576-586 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-41149101040&partnerID=MN8TOARS ER - TY - JOUR TI - Soil phosphorus forms after successive pig slurry application in a native pasture,Formas de fósforo no solo após sucessivas adições de dejeto líquido de suinos em pastagem natural AU - Gatiboni, L.C. AU - Brunetto, G. AU - Kaminski, J. AU - Dos Santos Rheinheimer, D. AU - Ceretta, C.A. AU - Basso, C.J. T2 - Revista Brasileira de Ciencia do Solo DA - 2008/// PY - 2008/// VL - 32 IS - 4 SP - 1753-1761 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-55849126650&partnerID=MN8TOARS ER - TY - JOUR TI - Soil microbial biomass phosphorus and activity of acid phosphatases during decline of soil available phosphorus,Fósforo da biomassa microbiana e atividade de fosfatases ácidas durante a diminuição do fósforo disponível no solo AU - Gatiboni, L.C. AU - Kaminski, J. AU - Rheinheimer, D.D.S. AU - Brunetto, G. T2 - Pesquisa Agropecuaria Brasileira DA - 2008/// PY - 2008/// VL - 43 IS - 8 SP - 1085-1091 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-52649111690&partnerID=MN8TOARS ER - TY - JOUR TI - Calcium:magnesium ratio in amendments of soil acidity: Nutrition and initial development of corn plants in a Humic Alic Cambisol,Relação cálcio:magnésio do corretivo da acidez do solo na nutrição e no desenvolvimento inicial de plantas de milho em um Cambissolo Húmico Álico AU - Medeiros, J.C. AU - Albuquerque, J.A. AU - Mafra, A.L. AU - Rosa, J.D. AU - Gatiboni, L.C. T2 - Semina:Ciencias Agrarias DA - 2008/// PY - 2008/// VL - 29 IS - 4 SP - 799-806 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-79958704944&partnerID=MN8TOARS ER - TY - SOUND TI - Sports Turf Research AU - Miller, Grady DA - 2008/1/15/ PY - 2008/1/15/ ER - TY - SOUND TI - Nutrition for High-Performance Turfgrass AU - Miller, Grady DA - 2008/1/15/ PY - 2008/1/15/ ER - TY - SOUND TI - Drought Tolerance Research Update AU - Miller, Grady DA - 2008/1/9/ PY - 2008/1/9/ ER - TY - SOUND TI - Granular Fertilizer Programs for Golf Courses AU - Miller, Grady DA - 2008/11/18/ PY - 2008/11/18/ ER - TY - SOUND TI - Answers To All Your Sports Turf Questions AU - Miller, Grady DA - 2008/1/8/ PY - 2008/1/8/ M3 - Workshop ER - TY - SOUND TI - Turfgrass Nutrition for Golf Courses AU - Miller, Grady DA - 2008/6/17/ PY - 2008/6/17/ ER - TY - SOUND TI - NCSU Research Update AU - Miller, Grady DA - 2008/1/7/ PY - 2008/1/7/ ER - TY - RPRT TI - Carolina Lawns: A guide to maintaining quality turf in the landscape AU - Bruneau, A.H. AU - Yelverton, F.H. AU - Tredway, L.P. AU - Brandenburg, R.L. AU - Bowman, D.C. AU - Peacock, C.H. AU - Miller, G.L. AU - Cooper, R.J. AU - Reynolds, C.W. AU - Chamblee, D.S. AU - Martin, M. A3 - North Carolina State University DA - 2008/// PY - 2008/// M3 - North Carolina Cooperative Extension Publication PB - North Carolina State University ER - TY - SOUND TI - Managing Sports Fields under Drought Conditions DA - 2008/4/15/ PY - 2008/4/15/ ER - TY - SOUND TI - Managing Sports Fields under Drought Conditions AU - Miller, Grady DA - 2008/3/27/ PY - 2008/3/27/ ER - TY - SOUND TI - Turf Selection for Drought AU - Miller, Grady DA - 2008/3/26/ PY - 2008/3/26/ ER - TY - CONF TI - Irrigation Uniformity on Golf Courses AU - Miller, Grady T2 - Western Turf Conference C2 - 2008/3/12/ CY - Hendersonville, NC DA - 2008/3/12/ PY - 2008/3/12/ ER - TY - SOUND TI - Practice Natural Lawn Care AU - Miller, Grady DA - 2008/3/17/ PY - 2008/3/17/ ER - TY - CONF TI - Drainage Design for Sports Fields AU - Miller, Grady T2 - Western Turf Conference C2 - 2008/3/12/ CY - Hendersonville, NC DA - 2008/3/12/ PY - 2008/3/12/ ER - TY - SOUND TI - Turfgrass Management under Drought Conditions AU - Miller, Grady DA - 2008/8/28/ PY - 2008/8/28/ ER - TY - SOUND TI - Role of Turfgrass in Society AU - Miller, Grady DA - 2008/11/25/ PY - 2008/11/25/ ER - TY - SOUND TI - Master of Ceremony at the Dedication of Turfgrass Pavilion AU - Miller, Grady DA - 2008/8/12/ PY - 2008/8/12/ ER - TY - SOUND TI - Turf Management in the Landscape AU - Miller, Grady DA - 2008/9/4/ PY - 2008/9/4/ ER - TY - CONF TI - Athletic Field Maintenance Practices AU - Miller, Grady T2 - NCRPA Conference C2 - 2008/11/10/ CY - Charlotte, NC DA - 2008/11/10/ PY - 2008/11/10/ ER - TY - SOUND TI - Golf Course Water Use Practices AU - Miller, Grady DA - 2008/9/3/ PY - 2008/9/3/ ER - TY - SOUND TI - Improving Ball Fields AU - Miller, Grady DA - 2008/10/15/ PY - 2008/10/15/ ER - TY - SOUND TI - Turfgrass Selection for Drought and non-Drought Conditions AU - Miller, Grady DA - 2008/5/29/ PY - 2008/5/29/ ER - TY - SOUND TI - Athletic Field Maintenance Practices AU - Miller, Grady DA - 2008/10/8/ PY - 2008/10/8/ ER - TY - SOUND TI - Sports Turf Management AU - Miller, Grady DA - 2008/9/16/ PY - 2008/9/16/ ER - TY - SOUND TI - Tall Fescue Management in Drought Conditions AU - Miller, Grady DA - 2008/12/4/ PY - 2008/12/4/ ER - TY - SOUND TI - Current Trends in Turfgrass Management AU - Miller, Grady DA - 2008/6/25/ PY - 2008/6/25/ ER - TY - SOUND TI - Nutrition and Turfgrass Fertilizers for Golf Courses AU - Miller, Grady DA - 2008/1/30/ PY - 2008/1/30/ ER - TY - SOUND TI - Warm-Season Athletic Field Management AU - Miller, Grady DA - 2008/1/18/ PY - 2008/1/18/ ER - TY - SOUND TI - Turfgrass BMPs AU - Miller, Grady DA - 2008/2/22/ PY - 2008/2/22/ ER - TY - SOUND TI - Establishment of Turfgrasses AU - Miller, Grady DA - 2008/2/21/ PY - 2008/2/21/ ER - TY - RPRT TI - Turfgrass heat and drought stress AU - Miller, G.L. A3 - North Carolina State University DA - 2008/6/10/ PY - 2008/6/10/ PB - North Carolina State University ER - TY - RPRT TI - Fall seeding of cool-season grass lawns – a water conservation effort AU - Peacock, C.H. AU - Miller, G.L. AU - Yelverton, F. A3 - North Carolina State University DA - 2008/8/21/ PY - 2008/8/21/ PB - North Carolina State University ER - TY - RPRT TI - How to deal with end of summer crabgrass infestation AU - Reynolds, C. AU - Miller, G.L. A3 - North Carolina State University DA - 2008/9/2/ PY - 2008/9/2/ PB - North Carolina State University ER - TY - RPRT TI - Turfgrass selection for drought survival and implications during non-drought periods AU - Miller, G.L. A3 - North Carolina State University DA - 2008/// PY - 2008/// PB - North Carolina State University ER - TY - RPRT TI - Turf drought issues agent in-service training AU - Peacock, C. AU - Bowman, D. AU - Grabbow, G. AU - Miller, G. AU - Martin, M. A3 - North Carolina State University DA - 2008/// PY - 2008/// PB - North Carolina State University ER - TY - RPRT TI - Managing spring seeded grasses AU - Miller, G.L. A3 - North Carolina State University DA - 2008/2/5/ PY - 2008/2/5/ PB - North Carolina State University ER - TY - RPRT TI - 2008 cool-season recommended variety list for North Carolina AU - Bruneau, A. AU - Miller, G. AU - Reynolds, C. A3 - North Carolina State University DA - 2008/// PY - 2008/// PB - North Carolina State University ER - TY - JOUR TI - Management plan for synthetics AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 IS - 5 SP - 50 ER - TY - MGZN TI - Overseeding bermudagrass with ryegrass AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 SP - 46 M1 - 11 ER - TY - MGZN TI - Dressing your field AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 SP - 50 M1 - 9 ER - TY - MGZN TI - Grassroots fields AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 SP - 54 M1 - 7 ER - TY - MGZN TI - Less water = tougher renovation AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 SP - 54 M1 - 3 ER - TY - MGZN TI - Needing more than eight glasses a day AU - Miller, G.L. T2 - SportsTurf DA - 2008/// PY - 2008/// VL - 24 SP - 74 M1 - 1 ER - TY - SOUND TI - Winter Seeding of Bermudagrass AU - Miller, Grady DA - 2008/8/13/ PY - 2008/8/13/ ER - TY - SOUND TI - Spring Seeding of Tall Fescue AU - Miller, Grady DA - 2008/8/13/ PY - 2008/8/13/ ER - TY - MGZN TI - Organic matter accumulation in bentgrass putting greens: How well can it be controlled? AU - Rufty, T. AU - Goodman, D. AU - Seth-Carley, D. AU - Bowman, D. AU - Miller, G. T2 - North Carolina Turfgrass DA - 2008/9// PY - 2008/9// SP - 10–14 ER - TY - CONF TI - Careful measurements and energy balance closure—The case of soil heat flux AU - Sauer, Thomas J. AU - Ochsner, Tyson E. AU - Heitman, Joshua L. AU - Horton, Robert AU - Tanner, Bert D. AU - Akinyemi, Olukayode D. AU - Hernandez-Ramirez, Guillermo AU - Moorman, Thomas B. C2 - 2008/1// C3 - Proceedings of the 28th Conference on Agricultural and Forest Meteorolog DA - 2008/1// UR - http://ams.confex.com/ams/pdfpapers/138960.pdf ER - TY - JOUR TI - Genomic targeting and mapping of tiller inhibition gene (tin3) of wheat using ESTs and synteny with rice AU - Kuraparthy, Vasu AU - Sood, Shilpa AU - Gill, Bikram S. T2 - Functional & Integrative Genomics DA - 2008/2// PY - 2008/2// DO - 10.1007/S10142-007-0057-4 VL - 8 IS - 1 SP - 33–42 SN - 1438-793X 1438-7948 UR - http://dx.doi.org/10.1007/S10142-007-0057-4 KW - comparative genomics KW - genome mapping KW - wheat KW - tillering KW - synteny KW - Triticum monococcum ER - TY - BOOK TI - Theoretical and Biological Foundations of Plant Breeding AU - Holland, J.B. AB - This chapter contains section titled: Of what use is theory for plant breeding? Current understanding of the regulation of gene function Reconciling the biological basis of gene expression and quantitative genetics theory Reconciling quantitative genetics theory and biological knowledge of gene expression The paradox of interactions at molecular level and additivity at the phenotypic level Conclusions Acknowledgments DA - 2008/// PY - 2008/// DO - 10.1002/9780470752708.ch9 SE - 127-140 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84889265588&partnerID=MN8TOARS ER - TY - JOUR TI - A comparison of leaf appearance rates among teosinte, maize landraces and modern maize AU - Van Esbroeck, G.A. AU - Ruiz Corral, J.A. AU - Sanchez Gonzalez, J.J. AU - Holland, J.B. T2 - Maydica DA - 2008/// PY - 2008/// VL - 53 IS - 2 SP - 117-123 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-57849127135&partnerID=MN8TOARS ER - TY - JOUR TI - Alien genetic resources for wheat leaf rust resistance, cytogenetic transfer, and molecular analysis AU - Gill, B. S. AU - Huang, L. AU - Kuraparthy, V. AU - Raupp, W. J. AU - Wilson, D. L. AU - Friebe, B. T2 - Australian Journal of Agricultural Research AB - Wild relatives of wheat are useful sources of alien resistance genes for wheat breeding. The objective of this review is to document research on the evaluation, transfer, and molecular analysis of alien resistance to wheat leaf rust especially in Aegilops tauschii, the diploid D-genome donor of common wheat. Nine named resistance genes (Lr1, Lr2, Lr15, Lr21, Lr22, Lr32, Lr34, Lr39, and Lr42) occur in the D genome. Twelve new leaf rust resistance genes have been documented in Ae. tauschii. The south-west Caspian Sea region is the centre of genetic diversity for seedling resistance. Adult-plant resistance is widespread in all geographic regions and should be exploited more in the future. Lr1 and Lr21 have been cloned and are typical NBS-LRR genes. The recent documentation of cryptic introgressions of Lr57/Yr40 from Ae. geniculata and Lr58 from Ae. triuncialis offers exciting possibilities for transferring alien genes without linkage drag. Both Lr21 and Lr34 presumably arose during or following the origin of common wheat ~8000 years ago. Leaf rust resistance genes often are located towards the physical ends of wheat chromosomes. These regions are known to be high in recombination, and this may explain their rapid rate of evolution. DA - 2008/// PY - 2008/// DO - 10.1071/AR07315 VL - 59 IS - 3 SP - 197 J2 - Aust. J. Agric. Res. LA - en OP - SN - 0004-9409 UR - http://dx.doi.org/10.1071/AR07315 DB - Crossref ER - TY - JOUR TI - A Subsurface, Closed-Loop System for Soil Carbon Dioxide and Its Application to the Gradient Efflux Approach AU - DeSutter, T. M. AU - Sauer, T. J. AU - Parkin, T. B. AU - Heitman, J. L. T2 - Soil Science Society of America Journal AB - Carbon dioxide concentrations in the soil can vary both temporally and spatially. Methodology was developed to semicontinuously measure subsurface concentrations of CO 2 using expanded, porous Teflon (ePTFE) tubing. Lengths of ePTFE tubing (7.6 m) were buried at 0.02, 0.1, and 0.18 m below the soil surface in a Harps loam soil (fine‐loamy, mixed, superactive, mesic Typic Calciaquoll) in central Iowa, and also positioned directly on the soil surface (0 m). Soil atmospheric gases that diffused through the walls of the tubing were circulated in a closed‐loop design through solid‐state CO 2 sensors to determine the concentration of CO 2 at each depth. Independent measures of CO 2 concentrations were also determined by sampling the in‐line gas stream of the ePTFE system and from samples extracted from gas wells positioned near the buried tubing. Good agreement ( r 2 > 0.95) was observed between the ePTFE system and the independent measures, with the ePTFE having biases of 1.2 and 1.37 times greater than the in‐line and gas well samples, respectively. The soil‐gas diffusion coefficient of CO 2 ( D s ) was determined using intact soil cores and values were about 2.5 times less than two popular models used to predict D s in soil. Estimates of CO 2 flux using Fick's Law, six approaches to determine the vertical CO 2 concentration gradient, and three methods to determine D s ranged from >800 to <1 μmol m −2 s −1 on Day of the Year 239.5. Although Fick's Law is commonly used to estimate CO 2 flux from soil, the approach used to determine the vertical CO 2 concentration gradient and method used to determine D s can both include sources of uncertainty. DA - 2008/1// PY - 2008/1// DO - 10.2136/sssaj2006.0101 VL - 72 IS - 1 SP - 126-134 J2 - Soil Sci. Soc. Am. J. LA - en OP - SN - 0361-5995 UR - http://dx.doi.org/10.2136/sssaj2006.0101 DB - Crossref ER - TY - JOUR TI - Evaluating Solarization and Cultivated Fallow for Johnsongrass (Sorghum halepense) Control and Nitrogen Cycling on an Organic Farm AU - Law, Derek M. AU - Bhavsar, Victoria AU - Snyder, John AU - Mullen, Michael D. AU - Williams, Mark T2 - Biological Agriculture & Horticulture AB - ABSTRACT A two-year field study evaluating efficacy of two weed control techniques on the noxious weed johnsongrass (Sorghum halepense L. Pers.) was conducted in Lexington KY. The weed control treatments were soil solarization, accomplished by covering the soil with clear plastic for 8 weeks, and cultivated bare fallow. Both treatments, along with a control treatment (mowing), were applied during the summers of 2003 and 2004 to a field heavily infested with johnsongrass (40–50% coverage). Effects of solarization on soil microbial activity and nitrogen (N) cycling were also evaluated. In both years, half of each treatment plot was lightly tilled 8 months after initial treatment application, and johnsongrass populations were characterized 2 months later. At the end of the experiment, the solarized-untilled treatment had lower johnsongrass populations than the cultivated-tilled and control treatments. Shallow tillage resulted in significantly more johnsongrass in the cultivated treatment in 2003, and in both cultivated and solarized treatments in 2004, compared with their untilled counterparts. At the conclusion of the experiment the johnsongrass populations were considerably reduced in both treatments compared with the original infestation. Solarization resulted in significant increases of both NH4-N and NO3-N in the soil during the time the plastic was in place, likely due to release of labile NH4-N from soil microbial biomass and subsequent nitrification. Substrate-induced respiration rates were also reduced during solarization, indicating a reduction of microbial biomass. However, these soil indicators were not persistent and should not prohibit the use of this weed management technique by organic growers. DA - 2008/1// PY - 2008/1// DO - 10.1080/01448765.2008.9755079 VL - 26 IS - 2 SP - 175-191 J2 - Biological Agriculture & Horticulture LA - en OP - SN - 0144-8765 2165-0616 UR - http://dx.doi.org/10.1080/01448765.2008.9755079 DB - Crossref ER - TY - JOUR TI - Differential requirement for β-catenin in epithelial and fiber cells during lens development AU - Cain, Sarah AU - Martinez, Gemma AU - Kokkinos, Maria I. AU - Turner, Kirsty AU - Richardson, Robert J. AU - Abud, Helen E. AU - Huelsken, Joerg AU - Robinson, Michael L. AU - de Iongh, Robb U. T2 - Developmental Biology AB - Recent studies implicate Wnt/beta-catenin signaling in lens differentiation (Stump, R. J., et al., 2003. A role for Wnt/beta-catenin signaling in lens epithelial differentiation. Dev Biol;259:48-61). Beta-catenin is a component of adherens junctions and functions as a transcriptional activator in canonical Wnt signaling. We investigated the effects of Cre/LoxP-mediated deletion of beta-catenin during lens development using two Cre lines that specifically deleted beta-catenin in whole lens or only in differentiated fibers, from E13.5. We found that beta-catenin was required in lens epithelium and during early fiber differentiation but appeared to be redundant in differentiated fiber cells. Complete loss of beta-catenin resulted in an abnormal and deficient epithelial layer with loss of E-cadherin and Pax6 expression as well as abnormal expression of c-Maf and p57(kip2) but not Prox1. There was also disrupted fiber cell differentiation, characterized by poor cell elongation, decreased beta-crystallin expression, epithelial cell cycle arrest at G(1)-S transition and premature cell cycle exit. Despite cell cycle arrest there was no induction of apoptosis. Mutant fiber cells displayed altered apical-basal polarity as evidenced by altered distribution of the tight junction protein, ZO1, disruption of apical actin filaments and abnormal deposition of extracellular matrix, resulting in a deficient lens capsule. Loss of beta-catenin also affected the formation of adhesion junctions as evidenced by dissociation of N-cadherin and F-actin localization in differentiating fiber cells. However, loss of beta-catenin from terminally differentiating fibers had no apparent effects on adhesion junctions between adjacent embryonic fibers. These data indicate that beta-catenin plays distinct functions during lens fiber differentiation and is involved in both Wnt signaling and adhesion-related mechanisms that regulate lens epithelium and early fiber differentiation. DA - 2008/9// PY - 2008/9// DO - 10.1016/j.ydbio.2008.07.002 VL - 321 IS - 2 SP - 420-433 J2 - Developmental Biology LA - en OP - SN - 0012-1606 UR - http://dx.doi.org/10.1016/j.ydbio.2008.07.002 DB - Crossref KW - lens development KW - Wnt signaling KW - adherens junctions KW - beta-catenin ER - TY - BOOK TI - Evaluation of limestone physical and chemical properties on neutralization capacity AU - Rippy, J.F.M. AU - Nelson, P.V. AU - Bilderback, T.E. AU - Swallow, W.H. AU - Hesterberg, D.L. AU - Kamprath, E.J. AU - Jahn, D. DA - 2008/// PY - 2008/// VL - 779 SE - 139-147 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-61449091576&partnerID=MN8TOARS ER - TY - CHAP TI - Cultivation practices for organic crops AU - Finney, D.M. AU - Creamer, N.G. AU - Monks, D.W. AU - Jennings, K.M. AU - Mitchem, W.E. T2 - Weed Management on Organic Farms. A2 - Finney, D.M. A2 - Creamer, N.G. PY - 2008/// SP - 14–28 PB - Center for Environmental Farming Systems UR - https://cefs.ncsu.edu/resources/weed-management-on-organic-farms/. ER - TY - CONF TI - Irrigation by evapotranspiration-based irrigation controllers in Florida AU - Davis, S.L. AU - Dukes, M.D. AU - Miller, G.L. T2 - 29th International Irrigation Conference C2 - 2008/// C3 - Proceedings of the 29th International Irrigation Conference CY - Anaheim, CA DA - 2008/// PY - 2008/11/2/ PB - Irrigation Association ER - TY - CONF TI - Controlled release nitrogen programs influence turfgrass quality AU - Miller, G.L. AU - Bruneau, A. AU - Reynolds, C. AU - Rufty, T. C2 - 2008/// C3 - European Turfgrass Society Conference Proceedings DA - 2008/// SP - 133–134 ER - TY - JOUR TI - Methodology for screening for resistance to Belonolaimus longicaudatus in turfgrass AU - Schwartz, B.M. AU - Kenworthy, K.E. AU - Crow, W.T. AU - Ferrell, J.A. AU - Miller, G.L. AU - Quesenberry, K.H. T2 - Nematropica DA - 2008/// PY - 2008/// VL - 38 IS - 2 SP - 163-175 ER - TY - CONF TI - Evaluation of Evapotranspiration-Based and Soil-Moisture-Based Irrigation Control in Turf AU - Grabow, Garry L. AU - Vasanth, Arjun AU - Bowman, Dan AU - Huffman, Rodney L. AU - Miller, Grady L. T2 - World Environmental and Water Resources Congress 2008 AB - A study was initiated in Fall 2006 in Raleigh, North Carolina to compare two types of commercially available irrigation control technologies, one based on estimates of evapotranspiration (ET) and the other based on feedback from soil moisture sensors. Water applied and turf quality from one ET-based system and two sensor-based systems were compared to a system using a standard time-based irrigation schedule. The effect of irrigation frequency was also a part of the study. Estimates of turf ET were obtained from the Penman-Monteith equation using on-site weather data, and also from an atmometer. Results from the twenty week evaluation in 2007 showed that on average the "add-on" soil-moisture-based system evaluated applied the least amount of water while the ET-based system evaluated applied the most water. Weekly irrigation frequencies used the least amount of water, followed by bi-weekly and daily frequencies in increasing amounts when averaged across all technologies. Minimally acceptable turf quality was maintained by all technologies and frequencies through most of the study, but turf quality declined substantially the last month of the study for the add-on system and standard timer-based system. The "on-demand" sensor-based system resulted in the best combination of water efficiency and turf quality. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)117 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)117 DB - Crossref ER - TY - JOUR TI - SURFACE WATER QUALITY ADJACENT TO GOLF COURSES IN THE SOUTHERN APPALACHIA AU - Rufty, T. AU - Bowman, D. AU - Miller, G. AU - Jennette, M. AU - Warren, L. AU - Carley, D.S. AU - Peacock, C. AU - Yelverton, F. T2 - Acta Horticulturae DA - 2008/2// PY - 2008/2// DO - 10.17660/actahortic.2008.783.23 VL - 2 IS - 783 SP - 229-238 J2 - Acta Hortic. OP - SN - 0567-7572 2406-6168 UR - http://dx.doi.org/10.17660/actahortic.2008.783.23 DB - Crossref KW - turfgrass KW - nitrate KW - nitrate pollution ER - TY - JOUR TI - AN EVALUATION OF CRUMB RUBBER AND CALCINED CLAY FOR TOPDRESSING SPORTS FIELDS AU - Miller, G.L. T2 - Acta Horticulturae DA - 2008/2// PY - 2008/2// DO - 10.17660/actahortic.2008.783.40 VL - 2 IS - 783 SP - 381-390 J2 - Acta Hortic. OP - SN - 0567-7572 2406-6168 UR - http://dx.doi.org/10.17660/actahortic.2008.783.40 DB - Crossref KW - topdress KW - surface hardness KW - soil moisture KW - root weight KW - bermudagrass ER - TY - CONF TI - Multiple disease resistance in interspecific-derived hybrid breeding lines AU - Tallury, S.P. AU - Isleib, T.G. AU - Hollowell, J. AU - Dong, W. AU - Milla-Lewis, S.R. AU - Holbrook, C.C. AU - Shew, B.B. C2 - 2008/// C3 - Proceedings of the American Peanut Research and Education Society DA - 2008/// VL - 40 SP - 32–33 ER - TY - CONF TI - SSR allelic diversity changes in Virginia-type peanut cultivars released from 1943 to 2006 AU - Milla-Lewis, S.R. AU - Zuleta, M.C. AU - Isleib, T.G. C2 - 2008/// C3 - Proceedings of the American Peanut Research and Education Society DA - 2008/// VL - 40 SP - 35–36 ER - TY - CONF TI - DNA markers for resistance to post-harvest aflatoxin accumulation in peanut (Arachis hypogaea L.) AU - Rowe, C.E. AU - Milla-Lewis, S.R. AU - Isleib, T.G. C2 - 2008/// C3 - Proceedings of the American Peanut Research and Education Society DA - 2008/// VL - 40 SP - 21–22 ER - TY - JOUR TI - Spatial Analysis of Soil Erosion and Sediment Fluxes: A Paired Watershed Study of Two Rappahannock River Tributaries, Stafford County, Virginia AU - Ricker, Matthew C. AU - Odhiambo, Ben K. AU - Church, Joseph M. T2 - Environmental Management DA - 2008/3/5/ PY - 2008/3/5/ DO - 10.1007/s00267-008-9094-6 VL - 41 IS - 5 SP - 766-778 J2 - Environmental Management LA - en OP - SN - 0364-152X 1432-1009 UR - http://dx.doi.org/10.1007/s00267-008-9094-6 DB - Crossref KW - spatial analysis KW - RUSLE KW - urbanization KW - Chesapeake Bay ER - TY - NEWS TI - How to: organic wheat storage T2 - Organic Grain Project Newsletter PY - 2008/// UR - http://www.organicgrains.ncsu.edu/Newsletters/June2008.htm ER - TY - JOUR TI - Cover cropping and soil disturbance impacts on the invertebrate weed seed predator Harpalus rufipes Degeer (Coleoptera:Carabidae) AU - Shearin, A.F. AU - Reberg-Horton, S.C. AU - Gallandt, E.R. T2 - Weed Science DA - 2008/// PY - 2008/// VL - 56 SP - 442–450 ER - TY - SOUND TI - Breeding rye cover crops for increased allelopathic potential AU - Reberg-Horton, S.C. AU - Brooks, A. AU - Danehower, D. AU - Burton, M. AU - Burton, J. AU - Ma, G. AU - Murphy, P. DA - 2008/// PY - 2008/// M3 - poster ER - TY - CONF TI - Improving weed suppressive ability in soybeans AU - Place, G.T. AU - Burton, M.G. AU - Reberg-Horton, S.C. C2 - 2008/// C3 - Proceedings of the 26th Annual Meeting of the Weed Science Society of North Carolina DA - 2008/// ER - TY - NEWS TI - Update on organic grain production research at NCSU – 2006-2007 T2 - Organic Grain Project Newsletter PY - 2008/// UR - http://www.organicgrains.ncsu.edu/Newsletters/June2008.htm ER - TY - JOUR TI - Soil fertility and tillage management for organic farming systems AU - Crozier, C.R. AU - Meijer, A.D. AU - Reberg-Horton, S.C. AU - Place, G.T. T2 - Soil Science Society of North Carolina Proceedings DA - 2008/// PY - 2008/// VL - 51 SP - 14–23 ER - TY - CONF TI - Seeding rate effects on weed control and yield in organic soybeans AU - Smith, A.N. AU - Place, G.T. AU - Reberg-Horton, S.C. C2 - 2008/// C3 - Proceedings of the 26th Annual Meeting of the Weed Science Society of North Carolina DA - 2008/// ER - TY - NEWS TI - Out-of-state organic grain bus tour summary T2 - Organic Grain Project Newsletter PY - 2008/9// UR - http://www.organicgrains.ncsu.edu/Newsletters/September2008.htm ER - TY - JOUR TI - Interspecific differences in weed susceptibility to steam injury AU - Leon, R.G. AU - Ferreira, D.T. T2 - Weed Technology AB - Thermal weed control methods have been incorporated into weed control programs in organic and conventional production systems. Flaming is commonly used, but steaming has been proposed to increase efficiency of heat transfer to weeds and reduce the risk of fire. The objective of this research was to measure injury to leaves of plant species that differ in leaf morphology and to measure injury to plants at different stages of plant development. The study was conducted in a glasshouse and plants were exposed to steaming at 400 C for 0.36 s—equivalent to a steaming speed of 2 km/h. Overall, leaf thickness was the best morphological characteristic to predict injury ( r 2 = 0.51), with greater thickness resulting in less injury. For broadleaf species only, species with wider leaves were injured more than species with narrower leaves ( r 2 = 0.64). Injury was greatest when plants had fewer than six true leaves and when their shoots were less than 10 cm long. There was a wide range of injury across species, and the grass species bermudagrass and perennial ryegrass were injured (68 to 81%) more than other species such as common purslane and English daisy (23 to 34%). Biomass of all species tested was reduced by approximately 40%, indicating that leaf injury was not the sole effect of steaming on plant growth. These results indicated that considering both visual estimates of injury and morphological characteristics is important to properly assess thermal weed control effectiveness. DA - 2008/// PY - 2008/// DO - 10.1614/wt-07-150.1 VL - 22 IS - 04 SP - 719–723 KW - Alternative weed management KW - steaming KW - heat KW - flaming KW - organic KW - physical KW - thermal KW - weed control ER - TY - JOUR TI - Soil phosphorus pools in Histosols under sugarcane and pasture in the Everglades, Florida AU - Castillo, M.S. AU - Wright, A.L. T2 - Geoderma AB - Land use changes in the Everglades Agricultural Area (EAA) in southern Florida may influence the distribution and availability of P. Cultivated soils in the EAA are being converted back to their historic use as seasonally-flooded prairies as part of Everglades restoration projects. The objectives of this study were to determine the distribution of P in soil chemical fractions in relation to long-term land management to predict P cycling and transformations for future land uses. Soil under pasture (100 yr) and planted to sugarcane (Saccharum sp.) for 50 yr were amended with P (0, 10, 50, 150 kg P ha− 1), and its distribution in labile, Fe–Al bound P, Ca-bound P, humic–fulvic acid P, and residual P pools determined for surface soil (0–15 cm). Most P fertilizer entered Fe–Al and Ca-bound fractions. Cultivation contributed to higher pH and increased the Ca content in soil compared to pasture due to incorporation of bedrock limestone into soil by tillage. The land uses were differentiated by P storage in different pools. Subsequently, long-term fertilization increased soil total P for cultivated soil relative to pasture, but plant-available P constituted less than 1% of the total P. Labile P increased with increasing P application rate, ranging from 1.3 to 7.2 mg kg− 1 for cultivated soil and 1.4 to 10.7 mg kg− 1 for pasture. Most of the applied P was recovered in the Fe–Al fraction for pasture and the Ca-bound P fraction for cultivated soil. The Ca-bound P fraction represented the greatest proportion of total P for sugarcane (41%), but only 12% for pasture. The majority of P in the pasture was present in the humic–fulvic acid fraction (45%), compared to only 23% for sugarcane. The higher pH of the cultivated soil (6.8) favored retention in Ca fractions while the lower pH of pasture (5.3) favored P retention in the humic–fulvic acid fraction. The proportion of total P as organic P was greater for pasture (78%) than cultivated soil (52%). Higher P levels in more recalcitrant fractions for cultivated soils indicated that more of the applied fertilizer P was sequestered in stable fractions, which decreased P availability to crops and may subsequently increase P fertilizer requirements necessary to maintain optimal plant-available nutrient levels. Subsequently, continuation of current farming practices and tillage regimes promotes the redistribution of Ca from subsurface to surface soil, which leads to greater P sequestration in the Ca-bound fraction. However, P in inorganic fractions may be released upon onset of changes in land use. Thus, conversion to seasonally-flooded prairies may have a more dramatic effect on P release from cultivated than pasture soils since cultivated soils have more P in inorganic pools. DA - 2008/// PY - 2008/// DO - 10.1016/j.geoderma.2008.03.006 VL - 145 IS - 1-2 SP - 130–135 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-43649087008&partnerID=MN8TOARS KW - everglades agricultural area KW - histosols KW - land use KW - phosphorus fractionation ER - TY - JOUR TI - Microbial activity and phosphorus availability in a subtropical soil under different land uses AU - Castillo, M.S. AU - Wright, A.L. T2 - World Journal of Agricultural Sciences DA - 2008/// PY - 2008/// VL - 4 SP - 314–320 J2 - World J. Agric. Sci. ER - TY - JOUR TI - Polyacrylamide and exchangeable cation effects on the hydraulic conductivity and flocculation of depositional seals made of different clays AU - Bhardwaj, A.K. AU - McLaughlin, R.A. AU - Shainberg, I. AU - Levy, G.J. T2 - Soil Science Society of America Journal DA - 2008/// PY - 2008/// VL - 73 SP - 910–918 ER - TY - CONF TI - Additional markers added to the fulghum/Norline genetic map and QTL scan for winter hardiness traits in Avena sativa C2 - 2008/// C3 - Proceedings, 8th International Oat Conference, Minneapolis, Minn. DA - 2008/// ER - TY - CONF TI - Proactive process-level live migration in HPC environments AU - Wang, C. AU - Mueller, F. AU - Engelmann, C. AU - Scott, S. L. AB - As the number of nodes in high-performance computing environments keeps increasing, faults are becoming common place. Reactive fault tolerance (FT) often does not scale due to massive I/O requirements and relies on manual job resubmission. This work complements reactive with proactive FT at the process level. Through health monitoring, a subset of node failures can be anticipated when one's health deteriorates. A novel process-level live migration mechanism supports continued execution of applications during much of processes migration. This scheme is integrated into an MPI execution environment to transparently sustain health-inflicted node failures, which eradicates the need to restart and requeue MPI jobs. Experiments indicate that 1-6.5 seconds of prior warning are required to successfully trigger live process migration while similar operating system virtualization mechanisms require 13-24 seconds. This self-healing approach complements reactive FT by nearly cutting the number of checkpoints in half when 70% of the faults are handled proactively. C2 - 2008/// C3 - International Conference for High Performance Computing, Networking, Storage and Analysis DA - 2008/// DO - 10.1109/sc.2008.5222634 SP - 126-137 ER - TY - JOUR TI - Rotation with corn and soybean for management of Meloidogyne incognita in cotton AU - Koenning, S. R. AU - Edmisten, K. L. T2 - Journal of Nematology DA - 2008/// PY - 2008/// VL - 40 IS - 4 SP - 258-265 ER - TY - JOUR TI - Grain yield and fusarium ear rot of maize hybrids developed from lines with varying levels of resistance AU - Eller, M.S. AU - Robertson-Hoyt, L.A. AU - Payne, G.A. AU - Holland, J.B. T2 - Maydica DA - 2008/// PY - 2008/// VL - 53 IS - 1-4 SP - 231-237 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-77956931980&partnerID=MN8TOARS ER - TY - JOUR TI - Effect of vegetation management on bird habitat in Riparian buffer zones AU - Smith, Timothy A. AU - Osmond, Deanna L. AU - Moorman, Christopher E. AU - Stucky, Jon M. AU - Gilliam, J. Wendell T2 - SOUTHEASTERN NATURALIST AB - Riparian buffers can be valuable refuge areas for wildlife in otherwise homogeneous agricultural landscapes. Government sponsored programs like the Cropland Reserve Program generally require the planting of specific vegetative species during buffer restoration, although the effectiveness of such an approach when compared to restoration by volunteer species is unknown. We studied the effect of differences in vegetation structure on avian habitat in riparian buffer zones. A 25 m (82 ft) wide planted woodland buffer, 30 m (98 ft) wide grass, shrub, and woodland three-zone buffer, and a 9 m (30 ft) wide shrub buffer were evaluated for habitat potential using breeding-bird counts and vegetation surveys. Bird density and species richness varied with the structure of the vegetative communities present at the three sites. Avian species richness and total detections were higher in the three-zone buffer than in both the shrub and planted buffer, likely a result of the diversity of vegetation at the site. These data suggest that restoration of riparian areas by allowing fallow vegetation to recolonize is at the very least equally beneficial to avian wildlife as is restoration by planting specific grass, shrub, and tree species. Buffer restoration by natural revegetation using this method could be recommended as an alternative to implementation by planting riparian species due to its simplicity and cost effectiveness. DA - 2008/// PY - 2008/// DO - 10.1656/1528-7092(2008)7[277:EOVMOB]2.0.CO;2 VL - 7 IS - 2 SP - 277-288 SN - 1938-5412 ER - TY - JOUR TI - Registration of RMUP-C5, a Random Mated Population of Upland Cotton Germplasm AU - Jenkins, J. N. AU - McCarty, J. C., Jr. AU - Gutierrez, O. A. AU - Hayes, R. W. AU - Bowman, D. T. AU - Watson, C. E. AU - Jones, D. C. T2 - JOURNAL OF PLANT REGISTRATIONS AB - RMUP‐C5 (Random Mated Upland Population Cycle 5) (Reg. No. GP‐893, PI 652942) is a unique random mated germplasm population of Upland cotton ( Gossypium hirsutum L.) involving six cycles of random mating beginning with an 11 parent half diallel. This germplasm was developed through cooperative research by the USDA‐ARS, Mississippi Agricultural and Forestry Experiment Station, North Carolina State Agricultural Experiment Station, and Cotton Incorporated. Parents used in development represented nonrelated or distantly related cultivars or breeding lines from across the U.S. Cotton Belt. The bulked pollen method of pollination was used in the development, and there were six cycles of random mating, with intercrossing of the F 1 considered cycle zero. Selfed seed of C 5 S 1 has been released. Changes in correlations between traits among parents, C 0 , and C 5 cycles show that after random mating, the C 5 population has recombinations that should be useful for selection and cultivar development. Because this germplasm represents random mating among 11 very diverse breeding programs and includes parents from the major seed breeding companies, this population should be of value to breeders across the U.S. Cotton Belt. DA - 2008/9// PY - 2008/9// DO - 10.3198/jpr2008.02.0080crg VL - 2 IS - 3 SP - 239-242 SN - 1936-5209 ER - TY - JOUR TI - Registration of 'N8001' Soybean AU - Carter, T. E., Jr. AU - Burton, J. W. AU - Fountain, M. O. AU - Rzewnicki, P. E. AU - Villagarcia, M. R. AU - Bowman, D. T. T2 - JOURNAL OF PLANT REGISTRATIONS AB - Journal of Plant RegistrationsVolume 2, Issue 1 p. 22-23 Cultivar Registration of ‘N8001’ Soybean T. E. Carter Jr., Corresponding Author T. E. Carter Jr. thomas.carter@ars.usda.gov USDA-ARS and Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Corresponding author (thomas.carter@ars.usda.gov).Search for more papers by this authorJ. W. Burton, J. W. Burton USDA-ARS and Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Search for more papers by this authorM. O. Fountain, M. O. Fountain USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorP. E. Rzewnicki, P. E. Rzewnicki USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorM. R. Villagarcia, M. R. Villagarcia USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorD. T. Bowman, D. T. Bowman Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Search for more papers by this author T. E. Carter Jr., Corresponding Author T. E. Carter Jr. thomas.carter@ars.usda.gov USDA-ARS and Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Corresponding author (thomas.carter@ars.usda.gov).Search for more papers by this authorJ. W. Burton, J. W. Burton USDA-ARS and Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Search for more papers by this authorM. O. Fountain, M. O. Fountain USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorP. E. Rzewnicki, P. E. Rzewnicki USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorM. R. Villagarcia, M. R. Villagarcia USDA-ARS, 3127 Ligon St., Raleigh, NC, 27607Search for more papers by this authorD. T. Bowman, D. T. Bowman Dep. of Crop Science, North Carolina State Univ., Raleigh, NC, 27695-7631Search for more papers by this author First published: 01 January 2008 https://doi.org/10.3198/jpr2007.03.0121crcCitations: 14 All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher. 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 onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume2, Issue1January 2008Pages 22-23 RelatedInformation DA - 2008/1// PY - 2008/1// DO - 10.3198/jpr2007.03.0121crc VL - 2 IS - 1 SP - 22-23 SN - 1940-3496 ER - TY - CONF TI - Lime pretreatment of switchgrass for bioethanol production AU - Xu, J. AU - Cheng, J. J. AU - Sharma-Shivappa, R. R. AU - Burns, J. C. AB - Lignocellulose-to-ethanol conversion is a promising technology to supplement corn-based ethanol production. To improve the enzymatic digestibility of lignocellulosic materials, pretreatment is necessary as it alters the structure of lignocellulosic matrix, thereby making the cellulose more accessible to cellulase enzymes during hydrolysis. In this research, switchgrass was used as lignocellulosic feedstock and lime was used as pretreatment agent to study the impact of lime loading, residence time and temperature on the reducing sugar yield of biomass after pretreatment. The results showed that lime pretreatment could effectively improve the digestibility of switchgrass at both high temperature and low temperature. At 121oC, increasing lime loading or extending residence time didnt necessarily favor the improvement of biomass digestibility. 15 min pretreatment with the lime loading of 0.10 g/g raw biomass was recommended. At 50oC, longer residence times were needed while the lime requirement didnt change. 24 h pretreatment with the lime loading of 0.10 g/g raw biomass was recommended. Using the recommended conditions, the reducing sugar yields of pretreated biomass were over 4 times that of unpretreated biomass. The research also showed that lime pretreatment was promising at even lower temperatures. At ambient temperature, the total reducing sugar yield from raw biomass reached 392 mg/g raw biomass after 24 h lime pretreatment, only 8% lower than that obtained under the recommended condition at 121oC or 50oC. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// DO - 10.13031/2013.24815 VL - 083998 ER - TY - CONF TI - Hydrolysis and fermentation of new switchgrass germplasm for bioethanol production AU - Yang, Y. AU - Sharma, R. R. AU - Burns, J. C. AU - Cheng, J. J. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// VL - 083799 ER - TY - JOUR TI - The challenge of making ozone risk assessment for forest trees more mechanistic AU - Matyssek, R. AU - Sandermann, H. AU - Wieser, G. AU - Booker, F. AU - Cieslik, S. AU - Musselman, R. AU - Ernst, D. T2 - ENVIRONMENTAL POLLUTION AB - Upcoming decades will experience increasing atmospheric CO2 and likely enhanced O3 exposure which represents a risk for the carbon sink strength of forests, so that the need for cause–effect related O3 risk assessment increases. Although assessment will gain in reliability on an O3 uptake basis, risk is co-determined by the effective dose, i.e. the plant's sensitivity per O3 uptake. Recent progress in research on the molecular and metabolic control of the effective O3 dose is reported along with advances in empirically assessing O3 uptake at the whole-tree and stand level. Knowledge on both O3 uptake and effective dose (measures of stress avoidance and tolerance, respectively) needs to be understood mechanistically and linked as a pre-requisite before practical use of process-based O3 risk assessment can be implemented. To this end, perspectives are derived for validating and promoting new O3 flux-based modelling tools. DA - 2008/12// PY - 2008/12// DO - 10.1016/j.envpol.2008.04.017 VL - 156 IS - 3 SP - 567-582 SN - 1873-6424 KW - O-3 flux KW - Sapflow KW - Effective O-3 dose KW - Detoxification KW - Mechanistic risk assessment ER - TY - JOUR TI - A Comparison of leaf appearance rates among teosinte, maize landraces and modern maize AU - Van Esbroeck, G. A. AU - Corral, J. A. R. AU - Gonzalez, J. J. S. AU - Holland, J. B. T2 - Maydica DA - 2008/// PY - 2008/// VL - 53 IS - 2 SP - 117-123 ER - TY - JOUR TI - Purple and Yellow Nutsedge (Cyperus rotundus and C. esculentus) Response to Postemergence Herbicides in Cotton AU - Burke, Ian C. AU - Troxler, Shawn C. AU - Wilcut, John W. AU - Smith, W. David T2 - WEED TECHNOLOGY AB - Greenhouse studies were conducted to evaluate the nature of the cotton postemergence (POST) herbicides followed by (fb) MSMA postemergence-directed (LAYBY) for foliar and tuber reduction of yellow and purple nutsedge when applied to nutsedge at two different application timings. Trifloxysulfuron at 4 and 6 g ai/ha fb MSMA LAYBY reduced 10- to 15- and 20- to 30-cm purple and yellow nutsedge root and shoot dry weights by at least 56%. However, the effect of weed size at the time of application was significant for trifloxysulfuron at 6 g/ha for percent root and shoot reductions in yellow nutsedge and percent root reduction in purple nutsedge. Significance of herbicide rate was only observed for percent shoot and root reduction of 10- to 15-cm yellow nutsedge. Trifloxysulfuron treatments reduced purple and yellow nutsedge shoot and root dry weights equivalent to treatments involving glyphosate POST fb MSMA LAYBY. MSMA at 1,120 and 2,240 g/ha and glufosinate POST fb MSMA LAYBY were effective for reducing purple and yellow nutsedge shoot dry weights, although percent reduction was influenced by nutsedge height at herbicide application. Treatments involving pyrithiobac POST fb MSMA LAYBY slightly increased 10- to 15-cm yellow nutsedge root dry weights. MSMA at either rate produced additive responses when included in tank mixtures with trifloxysulfuron at either rate or pyrithiobac POST fb MSMA LAYBY in yellow nutsedge. Other tank mixes or sequential combinations did not cause additive or synergistic responses. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-183.1 VL - 22 IS - 4 SP - 615-621 SN - 1550-2740 KW - Glufosinate KW - glyphosate KW - pyrithiobac KW - herbicide-resistant crops KW - LAYBY KW - MSMA KW - trifloxysulfuron ER - TY - JOUR TI - Influence of Graminicide Formulation on Compatibility with Other Pesticides AU - Lancaster, Sarah H. AU - Jordan, David L. AU - Johnson, P. Dewayne T2 - WEED TECHNOLOGY AB - Experiments were conducted from 2003 through 2006 to compare annual grass control by graminicides applied alone or with other pesticides and to determine whether graminicide formulation affected annual grass control and interactions with co-applied pesticides. Formulation and rate had no affect on broadleaf signalgrass or large crabgrass control by clethodim. The efficacy of clethodim in tank mixtures with acifluorfen plus bentazon, bentazon, chlorothalonil, imazapic, pyraclostrobin, or tebuconazole were not affected by clethodim formulation. Broadleaf signalgrass and large crabgrass control by clethodim was slightly reduced by acifluorfen plus bentazon, chlorothalonil, imazapic, and pyraclostrobin, but not by tebuconazole. Chlorothalonil and pyraclostrobin reduced broadleaf signalgrass control with quizalofop-P but did not reduce fall panicum control. Azoxystrobin, propiconazole, and tebuconazole did not affect efficacy of quizalofop-P. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-067.1 VL - 22 IS - 4 SP - 580-583 SN - 1550-2740 KW - Antagonism KW - formulation KW - integrated pest management KW - pesticide compatibility ER - TY - JOUR TI - A Comparison of Weed Control in Herbicide-Resistant, Herbicide-Tolerant, and Conventional Corn AU - Burke, Ian C. AU - Thomas, Walter E. AU - Allen, Jayla R. AU - Collins, Jim AU - Wilcut, John W. T2 - WEED TECHNOLOGY AB - Experiments were conducted at three North Carolina research stations in 2003 to evaluate weed control and corn yield in glyphosate-resistant, glufosinate-resistant, imidazolinone-tolerant, and conventional corn weed management systems. Late-season control of common lambsquarters, large crabgrass, and yellow nutsedge increased with metolachlor PRE compared with no PRE herbicide treatment. Common lambsquarters, pitted morningglory, entireleaf morningglory, spurred anoda, and tropic croton control was improved by a single early POST (EPOST) application regardless of herbicide system. Control of common lambsquarters, pitted morningglory, entireleaf morningglory, and spurred anoda was similar for glyphosate and glufosinate systems for each POST over-the-top (POT) herbicide system. A single EPOST application of imazethapyr plus imazapyr to imidazolinone-tolerant corn controlled common lambsquarters, pitted morningglory, entireleaf morningglory, and spurred anoda and was better than a single EPOST application of glyphosate, glufosinate, or nicosulfuron. Tropic croton was controlled ≥ 95% with glufosinate or glyphosate, applied once or twice, or in mixture with metolachlor. A single EPOST application of imazethapyr plus imazapyr or nicosulfuron did not control tropic croton. Common lambsquarters, entireleaf morningglory, large crabgrass, Palmer amaranth, and yellow nutsedge control was greater with a late-POST–directed (LAYBY) of ametryn than no LAYBY. Systems that did not include a POT herbicide system had the lowest percentage in the weed-free yield and the lowest yield. Treatments that included a POT system with or without a PRE treatment of metolachlor yielded within 5% of the weed-free treatment, regardless of herbicide system. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-184.1 VL - 22 IS - 4 SP - 571-579 SN - 0890-037X KW - Glufosinate resistant KW - glyphosate resistant KW - herbicide systems KW - imidazolinone tolerant KW - weed management ER - TY - JOUR TI - Mutations in a Delta(9)-Stearoyl-ACP-Desaturase Gene Are Associated with Enhanced Stearic Acid Levels in Soybean Seeds AU - Zhang, Ping AU - Burton, Joseph W. AU - Upchurch, Robert G. AU - Whittle, Edward AU - Shanklin, John AU - Dewey, Ralph E. T2 - CROP SCIENCE AB - Stearic acid (18:0) is typically a minor component of soybean [ Glycine max (L.) Merr.] oil, accounting for only 2 to 4% of the total fatty acid content. Increasing stearic acid levels of soybean oil would lead to enhanced oxidative stability, potentially reducing the need for hydrogenation, a process leading to the formation of undesirable trans fatty acids. Although mutagenesis strategies have been successful in developing soybean germplasm with elevated 18:0 levels in the seed oil, the specific gene mutations responsible for this phenotype were not known. We report a newly identified soybean gene, designated SACPD‐C , that encodes a unique isoform of Δ 9 –stearoyl‐ACP‐desaturase, the enzyme responsible for converting stearic acid to oleic acid (18:1). High levels of SACPD‐C transcript were only detected in developing seed tissue, suggesting that the encoded desaturase functions to enhance oleic acid biosynthetic capacity as the immature seed is actively engaged in triacylglycerol production and storage. The participation of SACPD‐C in storage triacylglycerol synthesis is further supported by the observation of mutations in this gene in two independent sources of elevated 18:0 soybean germplasm, A6 (30% 18:0) and FAM94‐41 (9% 18:0). A molecular marker diagnostic for the FAM94‐41 SACPD‐C gene mutation strictly associates with the elevated 18:0 phenotype in a segregating population, and could thus serve as a useful tool in the development of cultivars with oils possessing enhanced oxidative stability. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.02.0084 VL - 48 IS - 6 SP - 2305-2313 SN - 1435-0653 ER - TY - JOUR TI - Molecular Mapping and Confirmation of QTLs Associated with Oleic Acid Content in N00-3350 Soybean AU - Monteros, Maria J. AU - Burton, Joseph W. AU - Boerma, H. Roger T2 - CROP SCIENCE AB - The fatty acid composition of soybean [ Glycine max (L.) Merr.] seed affects the flavor, nutritional value, and stability of the oil. Increasing oleic acid content in soybean oil would reduce the need for hydrogenation, a process that creates unhealthy trans fatty acids. The objective of this study was to map and confirm the areas of the soybean genome associated with oleic acid content from the soybean line N00‐3350 (∼583 g kg −1 oleic acid) using simple sequence repeat (SSR) markers. An F 2:3 population of 259 lines from the cross of G99‐G725 × N00‐3350 was used as a mapping population, and an F 2:3 population of 231 lines from the cross of G99‐G3438 × N00‐3350 was used for confirmation. Using single‐factor analysis of variance, interval mapping, and composite interval mapping, six quantitative trait loci (QTLs) for oleic acid content were found on linkage groups LG‐A1 (Satt211, R 2 = 4%), LG‐D2 (Satt389, R 2 = 6%), LG‐G (Satt394, R 2 = 13%), LG‐G (Satt191, R 2 = 7%), LG‐L (Satt418, R 2 = 9%), and LG‐L (Satt561, R 2 = 25%) in the G99‐G725 × N00–3350 population. All six QTLs for oleic acid were confirmed in the G99‐3438 × N00‐3350 population. The designations cq Ole‐001, cq Ole‐002, cq Ole‐003, cq Ole‐004, cq Ole‐005, and cq Ole‐006 have been assigned to these confirmed QTLs by the Soybean Genetics Committee. The identification of SSR markers linked to the oleic acid QTLs will facilitate the use of marker‐assisted selection (MAS) in soybean breeding programs to increase the oleic acid content in soybean seed. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.05.0287 VL - 48 IS - 6 SP - 2223-2234 SN - 0011-183X ER - TY - JOUR TI - Evaluation of a Simple Method to Screen Soybean Genotypes for Salt Tolerance AU - Lee, Jeong-Dong AU - Smothers, Scotty L. AU - Dunn, David AU - Villagarcia, Margarita AU - Shumway, Calvin R. AU - Carter, Thomas E., Jr. AU - Shannon, J. Grover T2 - CROP SCIENCE AB - Excessive salt can reduce soybean yield [ Glycine max (L.) Merr.] in grower fields. Salt‐tolerant cultivars are needed to prevent field yield losses where excess salt is a problem. Soybean genotypes have primarily been evaluated for reaction to salt in the greenhouse using a labor‐intensive and costly hydroponics method. A reliable, inexpensive method to screen soybean lines for salt tolerance would be useful in breeding programs. A simple, inexpensive method of exposing V2 to V3 plants growing in a sandy soil in plastic cone‐tainers (PC method) was compared to the hydroponics method to evaluate soybean genotypes for salt tolerance in the greenhouse. Fourteen soybean genotypes including checks ‘Hutcheson’ (sensitive), and ‘S‐100’ and ‘Forrest’ (tolerant) were exposed to 100 mM salt solution at the V2 to V3 growth stage. Genotypes responded similarly to the screening methods except leaf scorch, an indicator of salt damage, appeared up to 4 d sooner in the PC method. The PC method was highly correlated with the hydroponics method for leaf scorch score and chloride content in soybean leaves among the 14 genotypes evaluated. Exposure of roots at the V2 to V3 growth stage to salt solution using the PC method was less labor intensive, consumed less time, was less costly, and gave similar results compared with the hydroponics method. Thus, the PC method is an easy, reliable method to screen soybean genotypes for salt tolerance. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.02.0090 VL - 48 IS - 6 SP - 2194-2200 SN - 1435-0653 ER - TY - JOUR TI - Efficacy of Transgenic Cotton Expressing Cry1Ac and Cry1F Insecticidal Protein Against Heliothines (Lepidoptera: Noctuidae) AU - Siebert, M. Willrich AU - Nolting, S. AU - Leonard, B. R. AU - Braxton, L. B. AU - All, J. N. AU - Van Duyn, J. W. AU - Bradley, J. R. AU - Bacheler, J. AU - Huckaba, R. M. T2 - JOURNAL OF ECONOMIC ENTOMOLOGY AB - Cotton, Cossypium hirsutum L, plants expressing Cry1Ac and Cry1F (Phytogen 440W) insecticidal crystal proteins of Bacillus thuringiensis (Bt) Berliner, were evaluated against natural populations of tobacco budworm, Heliothis virescens (F.), and bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), across 13 southern U.S. locations that sustained low, moderate, and high infestations. The intrinsic activity of Phytogen 440W was compared with nontreated non-Bt cotton (PSC355) and with management strategies in which supplemental insecticides targeting heliothines were applied to Phytogen 440W and to PSC355 cotton. Infestations were composed primarily of bollworm, which is the least sensitive of the heliothine complex to Cry toxins. Therefore, damage recorded in these studies was primarily due to bollworm. Greater than 75% of all test sites sustained heliothine infestations categorized as moderate to high (10.6-64.0% peak damaged bolls in nontreated PSC355). Phytogen 440W, alone or managed with supplemental insecticide applications, reduced heliothine-damaged plant terminals, squares (flower buds), flowers, and bolls equal to or better (1.0-79.0-fold) than managing a non-Bt cotton variety with foliar insecticides across all infestation environments. Rarely (frequency of < or = 11% averaged across structures), sprayed Phytogen 440W reduced damaged structures compared with nontreated Phytogen 440W. Protection against heliothine-induced plant damage was similar across the three levels of infestation for each viable management strategy, with exception to damaged squares for nontreated Phytogen 440W. In situations of moderate to high heliothine infestations, cotton plants expressing Cry1Ac and Cry1F may sustain higher levels of damage compared with that same variety in low infestations. No significant difference in yield was observed among heliothine management strategies within each infestation level, indicating cotton plants may compensate for those levels of plant damage. These findings indicate Phytogen 440W containing Cry1Ac and Cry1F provided consistent control of heliothines across a range of environments and infestation levels. DA - 2008/12// PY - 2008/12// DO - 10.1603/0022-0493-101.6.1950 VL - 101 IS - 6 SP - 1950-1959 SN - 0022-0493 KW - Bacillus thuringiensis KW - cotton KW - integrated pest management KW - tobacco budworm KW - bollworm ER - TY - JOUR TI - Simple polyacrylamide dosing systems for turbidity reduction in stilling basins AU - Bhardwaj, A. K. AU - McLaughlin, R. A. T2 - Transactions of the ASABE AB - Stilling basins are often ineffective in reducing turbidity and total suspended solids (TSS) in water containing fine sediments. This study determined the effectiveness of two polyacrylamide (PAM) dosing systems to flocculate suspended materials and the influence that porous baffles have on the two systems. Turbid water was generated by injecting soil into pond water flowing into a mixing basin for 30 min. Turbid water containing mostly fine suspended sediments was pumped from the surface of the mixing basin to a test stilling basin with physical and chemical treatments. The physical treatments were either an open basin or one with three porous baffles of 900 g m-3 coir matting. The chemical treatment was either passive using a PAM block or active using a PAM solution injected into the water pump intake at 4 mg L-1 in the pumped water. The passive treatment involved pumping turbid water over the PAM block at the basin entrance, dissolving the PAM as the water flowed over the block. Sampling for turbidity and total suspended solids (TSS) was done at 5 min intervals at the inlet, outlet weir, and four surface and bottom points inside the basin. In laboratory screening for PAM formulation and dose, tests conducted with whole soil resulted in greatly reduced turbidity, while those with only the suspended fraction had a much lower turbidity reduction. In the stilling basin, detention times of 1.5 or 24 h both had no effect on turbidity or TSS at the outlet. The turbidity of untreated discharges ranged from 220 to 260 nephelometric turbidity units (NTU), while both active and passive dosing significantly decreased the turbidity by 66% to 88%. Porous baffles had little effect compared to the PAM treatment. The active PAM treatment significantly reduced TSS at the outlet by up to 80%, but the 45% to 65% reduction by the passive system was not significantly different from the untreated tests. Patterns within the basins indicated that suspended flocs in PAM-treated water may have been intercepted and removed by the sloped dam wall, a phenomenon not observed in the untreated water. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25324 VL - 51 IS - 5 SP - 1653-1662 ER - TY - JOUR TI - Sediment trapping by five different sediment detention devices on construction sites AU - McCaleb, M. M. AU - McLaughlin, R. A. T2 - Transactions of the ASABE AB - Sediment pollution from construction sites has been of increasing concern, since the impacts on nearby streams can be severe. Five sediment trapping devices were monitored on construction sites in the Piedmont region of North Carolina to determine their trapping efficiency and the improvement in the water quality of their discharges. For each device, discharges were measured and sampled over periods of 5 to 13 months and the amount of trapped sediment was determined. Three of the devices were basins with rock outlets designed for 10-year recurrence storms with the following differences: one device was over excavated to have a 1 m standing pool, one device had silt fence baffles with weirs, and one device was open and fully drained. The fourth basin with a rock outlet was open and fully drained but sized for a 25-year storm. The fifth device was sized for a 25-year recurrence storm and had a floating surface outlet and solid riser spillways plus porous baffles within the basin. The three rock outlet basins that fully drained retained <40% of the sediment entering them regardless of their variations. However, the rock outlet basin with a 1 m standing pool retained 73% of the sediment for 16 of 17 storms. This could have been higher if the inlet and sides had been stabilized. The larger basin with surface outlets retained over 99% of the sediment it received until the floating outlet became mired in sediment, reducing the efficiency to 76%. Average discharge water quality was the highest for the standing pool and surface outlet designs, but all of the devices had very high turbidity and total suspended sediment (TSS) during peak flows. Maximum values for turbidity and TSS ranged from 16,000 to >30,000 nephelometric turbidity units (NTU) and from 20,000 to 168,000 mg L-1, respectively. There was a high correlation between turbidity and TSS among all the discharge samples. This study suggests that typical sediment traps are inadequate for retaining construction site sediment using current design criteria. It is possible, however, to have very effective sediment retention using recent advances in design. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25318 VL - 51 IS - 5 SP - 1613-1621 ER - TY - JOUR TI - Performance of lactating dairy cows fed varying levels of total mixed ration and pasture AU - Vibart, Ronaldo E. AU - Fellner, Vivek AU - Burns, Joseph C. AU - Huntington, Gerald B. AU - Green, James T., Jr. T2 - JOURNAL OF DAIRY RESEARCH AB - Two, 8-week experiments, each using 30 lactating Holstein cows, were conducted to examine performance of animals offered combinations of total mixed ration (TMR) and high-quality pasture. Experiment 1 was initiated in mid October 2004 and Experiment 2 was initiated in late March 2005. Cows were assigned to either a 100% TMR diet (100:00, no access to pasture) or one of the following three formulated partial mixed rations (PMR) targeted at (1) 85% TMR and 15% pasture, (2) 70% TMR and 30% pasture and (3) 55% TMR and 45% pasture. Based on actual TMR and pasture intake, the dietary TMR and pasture proportions of the three PMR in Experiment 1 were 79% TMR and 21% pasture (79:21), 68% TMR and 32% pasture (68:32), and 59% TMR and 41% pasture (59:41), respectively. Corresponding proportions in Experiment 2 were 89% TMR and 11% pasture (89:11), 79% TMR and 21% pasture (79:21) and 65% TMR and 35% pasture (65:35), respectively. Reducing the proportion of TMR in the diets increased pasture consumption of cows on all PMR, but reduced total dry matter intake compared with cows on 100:00. An increase in forage from pasture increased the concentration of conjugated linoleic acids and decreased the concentration of saturated fatty acids in milk. Although milk and milk protein yields from cows grazing spring pastures (Experiment 2) increased with increasing intakes of TMR, a partial mixed ration that was composed of 41% pasture grazed in the fall (Experiment 1) resulted in a similar overall lactation performance with increased feed efficiency compared to an all-TMR ration. DA - 2008/11// PY - 2008/11// DO - 10.1017/S0022029908003361 VL - 75 IS - 4 SP - 471-480 SN - 1469-7629 KW - Intake KW - pasture KW - partial mixed ration KW - grazing ER - TY - JOUR TI - Intra- and inter-specific density affects plant growth responses to arbuscular mycorrhizas AU - Schroeder-Moreno, Michelle S. AU - Janos, David P. T2 - BOTANY AB - Arbuscular mycorrhizas can alter competitive interactions between plants that markedly differ in their dependence upon mycorrhizas, but little is known about how mycorrhizas affect intra- and inter-specific competition between similarly dependent plant species. We conducted competition experiments in pots between all pairs of the similarly facultatively mycotrophic crop species, chili ( Capsicum annuum L.), maize ( Zea mays L.), and zucchini ( Cucurbita pepo L.). We used a two-species yield-density model to analyze the separate effects of mycorrhizal inoculation, intra-, and inter-specific density on biomass responses. Mycorrhizas reduced the growth of all three plant species. Intraspecific competition increased the negative effect of mycorrhizas, as did interspecific competition at low intraspecific density. At high intraspecific density, however, interspecific competition improved plant responsiveness to mycorrhizas. Enhancement of plant benefit from mycorrhizas at high interspecific density of competing, weakly mycorrhiza-dependent species may help to explain the evolutionary maintenance of their associations with mycorrhizal fungi, and may be a key to understanding intercrop combinations that exceed the monoculture yields of component species. DA - 2008/10// PY - 2008/10// DO - 10.1139/B08-080 VL - 86 IS - 10 SP - 1180-1193 SN - 1916-2804 KW - intraspecific competition KW - interspecific competition KW - facilitation KW - arbuscular mycorrhizas KW - facultative mycotrophs KW - yield-density model ER - TY - JOUR TI - Energy dissipation and chemical treatment to improve stilling basin performance AU - Bhardwaj, A. K. AU - McLaughlin, R. A. AU - Babcock, D. L. T2 - Transactions of the ASABE AB - Surface water pumped from construction sites frequently contains high levels of turbidity and suspended sediment, which are not effectively removed using gravity-based systems. This study assessed the effects of modifying a permanent pool stilling basin with energy dissipaters and with the addition of polyacrylamide (PAM) on turbidity and suspended sediments. Turbidity was generated by injecting soil into flowing water at a fixed rate for 30 min in a source basin. Turbid water from this basin was pumped from the surface to the stilling basin with physical and chemical treatments. Three energy dissipater treatments were tested: bottom inlet level spreader (BILS; silt fence fabric installed with 40 mm opening from the basin bottom), coir baffles (900 g m-2 coir fabric with 0.45 open space fraction (OSF), and Pyramat baffles (synthetic fabric with 0.10 OSF). The tests were run either with or without PAM dosing by passing the flow over a solid PAM block at the stilling basin inlet. The physical treatments (i.e., energy dissipation) did not significantly affect the turbidity and total suspended solids (TSS) of the water exiting the basin, which were reduced by up to 29% and 36%, respectively. The chemical treatment was much more effective regardless of the physical treatment, either in combination or alone, reducing turbidity and TSS up to 88% and 84%, respectively. The baffle materials collected much more suspended sediment when PAM was added, with twice as much sticking to the coir than the Pyramat, although overall the latter may be more effective in settling the flocs. The patterns of turbidity and TSS within the basin suggest that only one porous baffle is adequate for PAM-treated water, and that the reduction observed near the outlet was likely floc interception by the sloped wall of the basin outlet. This study provides a relatively simple, inexpensive approach to improving the function of stilling basins for treating turbid water. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25321 VL - 51 IS - 5 SP - 1645-1652 ER - TY - JOUR TI - PROTECTIVE EFFECT OF DIVALENT CATIONS AGAINST ALUMINUM TOXICITY IN SOYBEAN AU - Silva, Ivo Ribeiro AU - Cortes Correa, Tarcisio Fernando AU - Novais, Roberto Ferreira AU - Gebrim, Fabricio de Oliveira AU - Nunes, Flancer Novais AU - Salva, Eulene Francisco AU - Smyth, Thomas Jot T2 - REVISTA BRASILEIRA DE CIENCIA DO SOLO AB - A large proportion of soybean fields in Brazil are currently cultivated in the Cerrado region, where the area planted with this crop is growing considerably every year. Soybean cultivation in acid soils is also increasing worldwide. Since the levels of toxic aluminum (Al) in these acid soils is usually high it is important to understand how cations can reduce Al rhizotoxicity in soybean. In the present study we evaluated the ameliorative effect of nine divalent cations (Ca, Mg, Mn, Sr, Sn, Cu, Zn, Co and Ba) in solution culture on Al rhizotoxicity in soybean. The growth benefit of Ca and Mg to plants in an acid Inceptisol was also evaluated. In this experiment soil exchangeable Ca:Mg ratios were adjusted to reach 10 and 60 % base saturation, controlled by different amounts of CaCl2 or MgCl2 (at proportions from 100:0 up to 0:100), without altering the soil pH level. The low (10 %) and adequate (60 %) base saturation were used to examine how plant roots respond to Al at distinct (Ca + Mg)/Al ratios, as if they were growing in soils with distinct acidity levels. Negative and positive control treatments consisted of absence (under native soil or undisturbed conditions) or presence of lime (CaCO3) to reach 10 and 60 % base saturation, respectively. It was observed that in the absence of Aluminum, Cu, Zn, Co and Sn were toxic even at a low concentration (25 µmol L-1), while the effect of Mn, Ba, Sr and Mg was positive or absent on soybean root elongation when used in concentrations up to 100 µmol L-1. At a level of 10 µmol L-1 Al, root growth was only reverted to the level of control plants by the Mg treatment. Higher Tin doses led to a small alleviation of Al rhizotoxicity, while the other cations reduced root growth or had no effect. This is an indication that the Mg effect is ion-specific and not associated to an electrostatic protection mechanism only, since all ions were divalent and used at low concentrations. An increased exchangeable Ca:Mg ratio (at constant soil pH) in the acid soil almost doubled the soybean shoot and root dry matter even though treatments did not modify soil pH and exchangeable Al3+. This indicates a more efficient alleviation of Al toxicity by Mg2+ than by Ca2+. The reason for the positive response to Mg2+ was not the supply of a deficient nutrient because CaCO3 increased soybean growth by increasing soil pH without inducing Mg2+ deficiency. Both in hydroponics and acid soil, the reduction in Al toxicity was accompanied by a lower Al accumulation in plant tissue, suggesting a competitive cation absorption and/or exclusion of Al from plant tissue stimulated by an Mg-induced physiological mechanism. DA - 2008/// PY - 2008/// DO - 10.1590/s0100-06832008000500027 VL - 32 IS - 5 SP - 2061-2071 SN - 0100-0683 ER - TY - JOUR TI - Nitrate-N concentrations in the soil solution below reuse irrigated golf course fairways AU - Devitt, D. A. AU - Wright, L. AU - Bowman, D. C. AU - Morris, R. L. AU - Lockett, M. T2 - HortScience DA - 2008/// PY - 2008/// VL - 43 IS - 7 SP - 2196-2202 ER - TY - JOUR TI - Effect of Cyclanilide on Auxin Activity AU - Burton, James D. AU - Pedersen, Marianne K. AU - Coble, Harold D. T2 - JOURNAL OF PLANT GROWTH REGULATION DA - 2008/12// PY - 2008/12// DO - 10.1007/s00344-008-9062-7 VL - 27 IS - 4 SP - 342-352 SN - 1435-8107 KW - Cyclanilide KW - IAA KW - Auxin transport KW - Plant growth regulators ER - TY - JOUR TI - Cytogenetic characterization and nuclear DNA content of diploid and tetraploid forms of stokes aster AU - Barb, J. G. AU - Werner, D. J. AU - Tallury, S. P. T2 - HortScience DA - 2008/// PY - 2008/// VL - 43 IS - 7 SP - 2005-2012 ER - TY - JOUR TI - Crop Response to Rotation and Tillage in Peanut-Based Cropping Systems AU - Jordan, David L. AU - Barnes, J. Steven AU - Corbett, Tommy AU - Bogle, Clyde R. AU - Johnson, P. Dewayne AU - Shew, Barbara B. AU - Koenning, Stephen R. AU - Ye, Weimin AU - Brandenburg, Rick L. T2 - AGRONOMY JOURNAL AB - Production of peanut ( Arachis hypogaea L.) in reduced tillage systems has increased in the United States during the past decade. However, interactions of tillage system and crop rotation have not been thoroughly investigated for large‐seeded, Virginia market type peanut. Research was conducted at two locations in North Carolina during 1999 to 2006 to compare yield of corn ( Zea mays L.), cotton ( Gossypium hirsutum L.), and peanut in different rotations planted in conventional and reduced tillage. Crop rotation affected peanut yield but did not affect corn or cotton yield. Increasing the number of times corn, cotton, or a combination of these crops were planted between peanut increased peanut yields. Tillage affected cotton and peanut yield but not in every year or at both locations. Yield was similar in conventional and reduced tillage in 8 of 10 comparisons (cotton) and 6 of 8 comparisons (peanut). Crop rotation and tillage did not interact for visual estimates of plant condition of peanut as a result of disease, soil parasitic nematode populations when peanut was planted during the final year of the experiment, crop yield, cumulative net return over the duration of the experiment, or bulk density in the pegging zone during the final year of the experiment. These data suggest that variation in response to rotation and tillage should be expected based on the crop and edaphic and environmental conditions. However, response to rotation and tillage most likely will be independent. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2008.0075 VL - 100 IS - 6 SP - 1580-1586 SN - 1435-0645 ER - TY - JOUR TI - Cotton Subsurface Drip and Overhead Irrigation Efficiency, Maturity, Yield, and Quality AU - Whitaker, Jared R. AU - Ritchie, Glen L. AU - Bednarz, Craig W. AU - Mills, Cory I. T2 - AGRONOMY JOURNAL AB - Subsurface drip (SSD) is used as a water‐efficient alternative to overhead irrigation in many crops. This study compared soil water, water use, crop maturity, lint yield, and fiber quality of cotton ( Gossypium hirsutum L.) grown with SSD to cotton grown with overhead irrigation. Three experiments were conducted at two Georgia locations in 2004 and 2005. Treatments consisted of overhead irrigated, nonirrigated, SSD matched to overhead irrigation rates (SSD Matched), and SSD based on soil water (SSD Fed). Cotton maturity was affected by irrigation treatment as nonirrigated cotton matured earliest, whereas overhead irrigated cotton matured latest. Subsurface drip irrigated cotton produced similar or higher lint yields than overhead irrigated cotton. Subsurface drip provided adequate soil water and irrigation amounts were 4.4, 8.2, and 0.5 cm less than overhead irrigation at the three locations. Water use efficiency (WUE) of cotton SSD irrigated was 23 and 15% higher than overhead‐irrigated cotton in two experiments. Irrigation method did not substantially affect fiber quality; however, micronaire was higher in cotton from the SSD Fed treatment than cotton in the Overhead treatment in two locations. We conclude that SSD irrigation provides the same positive effects as overhead irrigation in cotton production while reducing irrigation water use and may allow for improved irrigation efficiency. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2008.0036 VL - 100 IS - 6 SP - 1763-1768 SN - 1435-0645 ER - TY - JOUR TI - BREEDING FOR IMPROVED RESISTANCE TO FUMONISIN CONTAMINATION IN MAIZE AU - Eller, Magen S. AU - Holland, James B. AU - Payne, Gary A. T2 - TOXIN REVIEWS AB - Maize grain infected by Fusarium verticillioides may contain the mycotoxin fumonisin, which is associated with livestock and human diseases. To reduce levels of fumonisin in grain, efforts are under way to identify sources of maize with increased resistance to fungal infection and fumonisin contamination. Field and laboratory techniques have been developed to measure both Fusarium ear rot and fumonisin contamination. Application of these techniques has led to the identification of resistant maize lines and facilitated genetic analysis of resistance to ear rot and fumonisin accumulation. Maize genetics and breeding studies are guiding strategies to improve resistance to fumonisin accumulation. DA - 2008/// PY - 2008/// DO - 10.1080/15569540802450326 VL - 27 IS - 3-4 SP - 371-389 SN - 1556-9551 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-77956939673&partnerID=MN8TOARS KW - Quantitative Trait Loci KW - fumonisin KW - Fusarium verticillioides ER - TY - JOUR TI - Absorption and Translocation of Foramsulfuron in Dallisgrass (Paspalum dilatatum) Following Preapplication of MSMA AU - Henry, G. AU - Burton, J. AU - Richardson, R. AU - Yelverton, F. T2 - WEED SCIENCE AB - Several field studies have observed increased foramsulfuron efficacy for the control of dallisgrass when foramsulfuron is applied after MSMA. Therefore, laboratory studies were conducted with mature dallisgrass to study the absorption and translocation of 14C-foramsulfuron, and then examine the impact of preliminary applications (preapplications) of MSMA or foramsulfuron on herbicide absorption and movement. Herbicide absorption increased rapidly through 4 h, and by 8 h, differences in absorption between pretreated and control plants were evident. After 48 h, foramsulfuron absorption in non-pretreated plants was 55%, whereas plants that received either pretreatment absorbed 70% of the herbicide. Translocation above (younger tissue) and below (older tissue) the treated leaf was 0.65 and 0.62% for non-pretreated plants, respectively. Pretreatment with foramsulfuron resulted in the translocation of 2.12 and 1.55% of applied radioactivity above and below the treated leaf, respectively. Pretreatment with MSMA resulted in the translocation of 2.33 and 2.34% of applied radioactivity above and below the treated leaf, respectively. These data indicated that pretreatment of mature dallisgrass with either foramsulfuron or MSMA results in an increase in both uptake and translocation of foramsulfuron applied 2 wk after pretreatment. The increase in absorption and translocation of foramsulfuron in the pre–MSMA-treated plants may explain the increase in control observed in the field when comparing it to the pre–foramsulfuron-treated dallisgrass plants. DA - 2008/// PY - 2008/// DO - 10.1614/WS-08-035.1 VL - 56 IS - 6 SP - 785-788 SN - 1550-2759 KW - Herbicide efficacy KW - translocation KW - herbicide interactions KW - golf course KW - liquid scintillation spectrometry KW - sulfonylurea herbicide KW - turfgrass ER - TY - JOUR TI - ASAS Centennial Paper: Utilization of pasture and forages by ruminants: A historical perspective AU - Burns, J. C. T2 - JOURNAL OF ANIMAL SCIENCE AB - Pastures, forages, and grasslands dominate the landscape across the United States and support a large ruminant population that supplies the nation with value-added animal products. A historical perspective is presented of the innovations as they occurred in the Journal of Animal Science over the past 100 yr in pasture and forage research. Consideration was given to both animal and pasture perspectives. Areas given consideration from the animal perspective were schemes for feedstuff analysis, experimental design and statistics, forage sample preservation, indirect methods of measuring intake and digestion, TDN and energy, nutritive value, harvested forage, and innovations in the grazing environment. Areas given consideration from the forage perspective were a framework for forage-animal interface research, determining pasture yield, choice of stocking method, grazing management, partitioning of forage DM, near-infrared reflectance spectroscopy technology, antiquality constituents, and forage sample preservation. Finally, the importance was discussed of applying research results from the forage-animal interface to general ruminant nutrition research beyond the interface that is focused on altered diets. DA - 2008/12// PY - 2008/12// DO - 10.2527/jas.2008-1240 VL - 86 IS - 12 SP - 3647-3663 SN - 1525-3163 KW - centennial KW - forage KW - forage-animal interface KW - historical KW - ruminant ER - TY - JOUR TI - POPULATION STRUCTURE AND GENETIC DIVERSITY OF NEW WORLD MAIZE RACES ASSESSED BY DNA MICROSATELLITES AU - Vigouroux, Yves AU - Glaubitz, Jeffrey C. AU - Matsuoka, Yoshihiro AU - Goodman, Major M. AU - Jesus Sanchez, G. AU - Doebley, John T2 - AMERICAN JOURNAL OF BOTANY AB - Because of the economic importance of maize and its scientific importance as a model system for studies of domestication, its evolutionary history is of general interest. We analyzed the population genetic structure of maize races by genotyping 964 individual plants, representing almost the entire set of ∼350 races native to the Americas, with 96 microsatellites. Using Bayesian clustering, we detected four main clusters consisting of highland Mexican, northern United States (US), tropical lowland, and Andean races. Phylogenetic analysis indicated that the southwestern US was an intermediary stepping stone between Mexico and the northern US. Furthermore, southeastern US races appear to be of mixed northern flint and tropical lowland ancestry, while lowland middle South American races are of mixed Andean and tropical lowland ancestry. Several cases of post‐Columbian movement of races were detected, most notably from the US to South America. Of the four main clusters, the highest genetic diversity occurs in highland Mexican races, while diversity is lowest in the Andes and northern US. Isolation by distance appears to be the main factor underlying the historical diversification of maize. We identify highland Mexico and the Andes as potential sources of genetic diversity underrepresented among elite lines used in maize breeding programs. DA - 2008/10// PY - 2008/10// DO - 10.3732/ajb.0800097 VL - 95 IS - 10 SP - 1240-1253 SN - 0002-9122 KW - diversification KW - domestication KW - genetic diversity KW - microsatellites KW - races KW - Zea mays subsp mays ER - TY - JOUR TI - Influence of ultranarrow row and conventional row cotton on the last effective boll population AU - Viator, Ryan P. AU - Gwathmey, C. Owen AU - Cothren, J. Tom AU - Reed, Jack T. AU - Vories, Earl D. AU - Nuti, Russell C. AU - Edmisten, Keith L. AU - Wells, Randy T2 - AGRONOMY JOURNAL AB - The last effective boll population (LEBP) is the basis for many cotton ( Gossypium hirsutum L.) management decisions such as defoliation timing. The objective of this research was to determine the last effective boll population based on first position bolls for both ultranarrow row cotton (UNRC), grown in rows spaced 25 cm or less, and conventional cotton (CONC) grown in rows spaced 96 to 102 cm. Experimental sites included locations in North Carolina, Tennessee, Mississippi, Arkansas, and Texas. At each site, UNRC and CONC plots were planted in a RCB design. At first flower, 15 plants per plot were flagged for subsequent flower tagging. On each flagged plant, all first position flowers were tagged every 2 d throughout the reproductive stage with date and nodes above white flower (NAWF) data for each plant. Tagged bolls were handpicked, sorted, counted, and seedcotton was weighed and recorded by NAWF for each plot. The last effective boll population was considered that NAWF position where cotton could be economically produced. Cotton could be produced economically at NAWF 2 and 3 for UNRC and CONC, respectively. Lint yield did not differ significantly between UNRC and CONC across site‐years. The UNRC produced the majority of seedcotton on NAWF 3 to 5, while CONC produced the most seedcotton at NAWF 4 to 6. Boll numbers showed a similar pattern. These data demonstrate that physiological cutout occurred at NAWF <5 in both UNRC and CONC. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2007.0289 VL - 100 IS - 5 SP - 1327-1331 SN - 1435-0645 ER - TY - JOUR TI - Economic Evaluation of Methyl Bromide Alternatives for the Production of Tomatoes in North Carolina AU - Sydorovych, Olha AU - Safley, Charles D. AU - Welker, Rob M. AU - Ferguson, Lisa M. AU - Monks, David W. AU - Jennings, Katie AU - Driver, Jim AU - Louws, Frank J. T2 - HortTechnology AB - Partial budget analysis was used to evaluate soil treatment alternatives to methyl bromide (MeBr) based on their efficacy and cost-effectiveness in the production of tomato ( Solanum lycopersicum ). The analysis was conducted for the mountain tomato production region based on 6 years of field test data collected in Fletcher, NC. Fumigation alternatives evaluated included 61.1% 1,3-dichloropropene + 34.7% chloropicrin (Telone-C35™), 60.8% 1,3-dichloropropene + 33.3% chloropicrin (InLine), 99% chloropicrin (Chlor-o-pic), 94% chloropicrin (TriClor EC), 42% metam sodium (4.26 lb/gal a.i., Vapam), and 50% iodomethane + 50% chloropicrin (Midas). The MeBr formulation was 67% methyl bromide and 33% chloropicrin (Terr-O-Gas). Chloropicrin applied at 15 gal/acre provided the greatest returns with an additional return of $907/acre relative to MeBr. Telone-C35 provided an additional return of $848/acre and drip-applied metam sodium provided an additional return of $137/acre. The return associated with broadcast applied metam sodium was about equal to the estimated return a grower would receive when applying MeBr. Fumigating with a combination of chloropicrin and metam sodium; shank-applied chloropicrin at 8 gal/acre; drip-applied chloropicrin, Midas, or InLine; and the nonfumigated soil treatment all resulted in projected losses of $156/acre, $233/acre, $422/acre, $425/acre, $604/acre, and $2133/acre, respectively, relative to MeBr. Although technical issues currently associated with some of the MeBr alternatives may exist, results indicate that there are economically feasible fumigation alternatives to MeBr for production of tomatoes in North Carolina. DA - 2008/1// PY - 2008/1// DO - 10.21273/horttech.18.4.705 VL - 1 IS - 4 SP - 705-713 OP - SN - 1063-0198 1943-7714 UR - http://dx.doi.org/10.21273/horttech.18.4.705 DB - Crossref KW - cost of production KW - partial budget analysis KW - fumigation KW - Solanum lycopersicum ER - TY - JOUR TI - Cysteine proteases XCP1 and XCP2 aid micro-autolysis within the intact central vacuole during xylogenesis in Arabidopsis roots AU - Avci, Utku AU - Petzold, H. Earl AU - Ismail, Ihab O. AU - Beers, Eric P. AU - Haigler, Candace H. T2 - PLANT JOURNAL AB - Establishing the mechanisms regulating the autolysis of xylem tracheary elements (TEs) is important for understanding this programmed cell death process. These data demonstrate that two paralogous Arabidopsis thaliana proteases, XYLEM CYSTEINE PROTEASE1 (XCP1) and XCP2, participated in micro-autolysis within the intact central vacuole before mega-autolysis was initiated by tonoplast implosion. The data acquisition was aided by the predictable pattern of seedling root xylogenesis, the availability of single and double total knock-out T-DNA lines, anti-sera that recognized XCP1 and XCP2, and the microwave-assisted processing of whole seedlings prior to immunolabeling and observation in the transmission electron microscope. During secondary wall thickening, XCP1 and XCP2 (in wild type), XCP1 (in xcp2 seedlings) or XCP2 (in xcp1 seedlings) were imported into the TE central vacuole. Both XCP1 and XCP2 heavily labeled dense aggregates of material within the vacuole. However, because of XCP1 deficiency in xcp1 and xcp1 xcp2 TEs, non-degraded cellular remnants first accumulated in the vacuole and then persisted in the TE lumen (longer than in the wild type) after the final mega-autolysis was otherwise complete. This delayed TE clearing phenotype in xcp1 was rescued by complementation with wild-type XCP1. Although TEs in the xcp2 single knock-out cleared comparably with wild type, the non-degraded remnants in xcp1 xcp2 TEs were more densely packed than in xcp1 TEs. Therefore, XCP2 has a minor but distinct role in micro-autolysis. After tonoplast implosion, XCP1 and XCP2 remained associated with disintegrating cellular material as mega-autolysis, aided by additional lytic enzymes, destroyed the bulk of the cellular contents. DA - 2008/10// PY - 2008/10// DO - 10.1111/j.1365-313X.2008.03592.x VL - 56 IS - 2 SP - 303-315 SN - 1365-313X KW - programmed cell death KW - tracheary element autolysis KW - cysteine protease KW - vacuole KW - microwave-assisted fixation KW - immunolabeling ER - TY - JOUR TI - Characterizing ammonia emissions from swine farms in eastern north carolina: Part 1-conventional lagoon and spray technology for waste treatment AU - Aneja, Viney P. AU - Arya, S. Pal AU - Kim, D. -S. AU - Rumsey, Ian C. AU - Arkinson, H. L. AU - Semunegus, H. AU - Bajwa, K. S. AU - Dickey, D. A. AU - Stefanski, L. A. AU - Todd, L. AU - Mottus, K. AU - Robarge, W. P. AU - Williams, C. M. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - Abstract Ammonia (NH3) fluxes from waste treatment lagoons and barns at two conventional swine farms in eastern North Carolina were measured. The waste treatment lagoon data were analyzed to elucidate the temporal (seasonal and diurnal) variability and to derive regression relationships between NH3 flux and lagoon temperature, pH and ammonium content of the lagoon, and the most relevant meteorological parameters. NH3 fluxes were measured at various sampling locations on the lagoons by a flow-through dynamic chamber system interfaced to an environmentally controlled mobile laboratory. Two sets of open-path Fourier transform infrared (FTIR) spectrometers were also used to measure NH3 concentrations for estimating NH3 emissions from the animal housing units (barns) at the lagoon and spray technology (LST) sites.Two different types of ventilation systems were used at the two farms. Moore farm used fan ventilation, and Stokes farm used natural ventilation. The early fall and winter season intensive measurement campaigns were conducted during September 9 to October 11, 2002 (lagoon temperature ranged from 21.2 to 33.6 °C) and January 6 to February 2, 2003 (lagoon temperature ranged from 1.7 to 12 °C), respectively. Significant differences in seasonal NH3 fluxes from the waste treatment lagoons were found at both farms. Typical diurnal variation of NH3 flux with its maximum value in the afternoon was observed during both experimental periods. Exponentially increasing flux with increasing surface lagoon temperature was observed, and a linear regression relationship between logarithm of NH3 flux and lagoon surface temperature (T l) was obtained. Correlations between lagoon NH3 flux and chemical parameters, such as pH, total Kjeldahl nitrogen (TKN), and total ammoniacal nitrogen (TAN) were found to be statistically insignificant or weak. In addition to lagoon surface temperature, the difference (D) between air temperature and the lagoon surface temperature was also found to influence the NH3 flux, especially when D > 0 (i.e., air hotter than lagoon). This hot-air effect is included in the statistical-observational model obtained in this study, which was used further in the companion study (Part II), to compare the emissions from potential environmental superior technologies to evaluate the effectiveness of each technology. DA - 2008/9// PY - 2008/9// DO - 10.3155/1047-3289.58.9.1130 VL - 58 IS - 9 SP - 1130-1144 SN - 1047-3289 ER - TY - JOUR TI - Characterizing ammonia emissions from swine farms in eastern North Carolina: Part 2 - Potential environmentally superior technologies for waste treatment AU - Aneja, Viney P. AU - Arya, S. Pal AU - Rumsey, Ian C. AU - Kim, D. -S. AU - Bajwa, K. AU - Arkinson, H. L. AU - Semunegus, H. AU - Dickey, D. A. AU - Stefanski, L. A. AU - Todd, L. AU - Mottus, K. AU - Robarge, W. P. AU - Williams, C. M. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - The need for developing environmentally superior and sustainable solutions for managing the animal waste at commercial swine farms in eastern North Carolina has been recognized in recent years. Program OPEN (Odor, Pathogens, and Emissions of Nitrogen), funded by the North Carolina State University Animal and Poultry Waste Management Center (APWMC), was initiated and charged with the evaluation of potential environmentally superior technologies (ESTs) that have been developed and implemented at selected swine farms or facilities. The OPEN program has demonstrated the effectiveness of a new paradigm for policy-relevant environmental research related to North Carolina's animal waste management programs. This new paradigm is based on a commitment to improve scientific understanding associated with a wide array of environmental issues (i.e., issues related to the movement of N from animal waste into air, water, and soil media; the transmission of odor and odorants; disease-transmitting vectors; and airborne pathogens). The primary focus of this paper is on emissions of ammonia (NH3) from some potential ESTs that were being evaluated at full-scale swine facilities. During 2-week-long periods in two different seasons (warm and cold), NH3 fluxes from water-holding structures and NH3 emissions from animal houses or barns were measured at six potential EST sites: (1) Barham farm--in-ground ambient temperature anaerobic digester/energy recovery/greenhouse vegetable production system; (2) BOC #93 farm--upflow biofiltration system--EKOKAN; (3) Carrolls farm--aerobic blanket system--ISSUES-ABS; (4) Corbett #1 farm--solids separation/ gasification for energy and ash recovery centralized system--BEST; (5) Corbett #2 farm--solid separation/ reciprocating water technology--ReCip; and (6) Vestal farm--Recycling of Nutrient, Energy and Water System--ISSUES-RENEW. The ESTs were compared with similar measurements made at two conventional lagoon and spray technology (LST) farms (Moore farm and Stokes farm). A flow-through dynamic chamber system and two sets of open-path Fourier transform infrared (OP-FTIR) spectrometers measured NH3 fluxes continuously from water-holding structures and emissions from housing units at the EST and conventional LST sites. A statistical-observational model for lagoon NH3 flux was developed using a multiple linear regression analysis of 15-min averaged NH3 flux data against the relevant environmental parameters measured at the two conventional farms during two different seasons of the year. This was used to compare the water-holding structures at ESTs with those from lagoons at conventional sites under similar environmental conditions. Percentage reductions in NH3 emissions from different components of each potential EST, as well as the whole farm on which the EST was located were evaluated from the estimated emissions from water-holding structures, barns, etc., all normalized by the appropriate nitrogen excretion rate at the potential EST farm, as well as from the appropriate conventional farm. This study showed that ammonia emissions were reduced by all but one potential EST for both experimental periods. However, on the basis of our evaluation results and analysis and available information in the scientific literature, the evaluated alternative technologies may require additional technical modifications to be qualified as unconditional ESTs relative to NH3 emissions reductions. DA - 2008/9// PY - 2008/9// DO - 10.3155/1047-3289.58.9.1145 VL - 58 IS - 9 SP - 1145-1157 SN - 2162-2906 ER - TY - JOUR TI - Breeding Fhb-resistant soft winter wheat: Progress and prospects AU - Brown-Guedira, Gina AU - Griffey, Carl AU - Kolb, Fred AU - Mckendry, Anne AU - Murphy, J. Paul AU - Van Sanford, David T2 - CEREAL RESEARCH COMMUNICATIONS AB - Soft winter wheat ( Triticum aestivum L.) breeding programs in the US have used two general approaches to developing FHB-resistant cultivars: 1) incorporation of Fhb 1 plus other minor QTL from Asian wheat cultivars and their derivatives and 2) reliance on resistance native to the soft winter wheat gene pool. Although each approach has shown some success, it is believed that the two must be integrated to develop the highest levels of resistance. The most favorable scenario for integration is the incorporation of Fhb 1 into adapted material with good native resistance, high yield and test weight, and superior milling and baking quality. DA - 2008/// PY - 2008/// DO - 10.1556/crc.36.2008.suppl.b.5 VL - 36 SP - 31-35 SN - 1788-9170 KW - fusarium head blight KW - wheat breeding KW - resistance ER - TY - JOUR TI - Activity of the 5 ' regulatory regions of the rice polyubiquitin rubi3 gene in transgenic rice plants as analyzed by both GUS and GFP reporter genes AU - Lu, Jianli AU - Sivamani, Elumalai AU - Li, Xianggan AU - Qu, Rongda T2 - PLANT CELL REPORTS DA - 2008/10// PY - 2008/10// DO - 10.1007/s00299-008-0577-y VL - 27 IS - 10 SP - 1587-1600 SN - 1432-203X KW - GFP KW - GUS KW - intron KW - rice rubi3 promoter KW - transgenic plant ER - TY - JOUR TI - 'Coastal' and 'Tifton 44' bermudagrass availability on animal and pasture productivity AU - Burns, J. C. AU - Fisher, D. S. T2 - AGRONOMY JOURNAL AB - Hybrid cultivars of bermudagrass [ Cynodon dactylon (L.) Pers.] are a major feed source for ruminants across the southeastern United States. This 4‐yr experiment compared animal and pasture performance of ‘Coastal’ and ‘Tifton 44’ bermudagrasses over three canopy heights designated as short (5.6 cm), medium (10.1 cm), and tall (13.1 cm). The relationship of canopy height to ingestive mastication and canopy characteristics was also studied. Soil was a Cecil clay loam (clayey, Kaolinitic thermic Typic Hapludult). Pastures were continuously stocked using variable stocking to maintain the targeted canopy heights. Herbage mass (to soil surface) was similar between Coastal and Tifton 44 (T44) within each canopy height averaging 2.36, 4.08, and 5.25 Mg ha −1 . Steer average daily gain (ADG) was greater ( P = 0.09) from T44 than Coastal (0.58 vs. 0.51 kg) but no differences were noted in pasture productivity. Increasing herbage mass linearly increased ( P < 0.01) ADG (0.40–0.59 kg) but reduced ( P < 0.01) stocking rate (16.1–11.2 steers ha −1 ), which influenced animal days (1810–1079 d ha −1 ), weight gain (1057–786 kg ha −1 ), and effective feed units (6392–4452 kg ha −1 ). Steer ADG increased ( P = 0.01) from short to medium canopy height (0.40–0.64 kg) with little change between medium and tall canopy height (0.64–0.59 kg). Tifton 44 pasture is of greater quality than Coastal giving greater ADG but both were productive producing about 1100 kg of gain ha −1 when effectively managed and utilized. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2007.0381 VL - 100 IS - 5 SP - 1280-1288 SN - 0002-1962 ER - TY - JOUR TI - The effect of postemergence herbicides on the spectral reflectance of corn AU - Everman, Wesley J. AU - Medlin, Case R. AU - Dirks, Richard D., Jr. AU - Bauman, Thomas T. AU - Biehl, Larry T2 - WEED TECHNOLOGY AB - Studies were conducted in 2001 and 2002 to determine the effect of POST herbicides on the spectral reflectance of corn. POST corn herbicides evaluated included 2,4-D, atrazine, bromoxynil, dicamba + diflufenzopyr, nicosulfuron, and primisulfuron. Multispectral and hyperspectral data were collected and spectral properties were analyzed using SAS procedures and MultiSpec image analysis. Corn treated with POST applications of atrazine and primisulfuron could not be distinguished from nontreated corn regardless of data type or analysis method used. 2,4-D and dicamba + diflufenzopyr were the most readily distinguished from nontreated corn plots using both hyperspectral and multispectral data. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-021.1 VL - 22 IS - 3 SP - 514-522 SN - 1550-2740 KW - precision agriculture KW - precision weed control KW - site-specific herbicide application ER - TY - JOUR TI - Testing for variation in animal preference for Jesup tall fescue hays with wild-type, novel, or no fungal endophyte AU - Fisher, D. S. AU - Burns, J. C. T2 - CROP SCIENCE AB - Tall fescue [ Schedonorus phoenix (Scop.) Holub.] is an important source of forage but often contains a fungal endophyte [ Neotyphodium coenophialum (Morgan‐Jones and Gams) Glenn, Bacon, and Hanlin] that can produce alkaloids and decrease animal performance. Removing the endophyte can reduce agronomic performance and persistence. An improved cultivar (‘Jesup’) with a novel (nontoxic) endophyte (trademark “MaxQ”) has improved agronomic performance. Persistence may be related to agronomic traits and animal feeding preferences. We tested for variation in animal preference among two harvests by testing each of three hays made from Jesup tall fescue that varied in endophyte status (no endophyte, containing the novel endophyte, or containing a wild‐type endophyte that produces alkaloids associated with toxicosis). We tested for preference using goats ( Capra hircus ), sheep ( Ovis aries ), and cattle ( Bos taurus ). All possible pairs were tested using traditional analysis of variance as well as multidimensional scaling. Multidimensional scaling of the animal preferences indicated that two dimensions were being used to rank the hays. The first dimension for all three animal species was related to variation in forage nutritive value. The second dimension was not correlated with any of the measured variables. Endophyte status was not a factor in the preferences expressed by the three animal species. It appears that no effective feedback mechanism exists related to endophyte status. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.10.0548 VL - 48 IS - 5 SP - 2026-2032 SN - 0011-183X ER - TY - JOUR TI - Temperature response of Benghal dayflower (Commelina benghalensis): Implications for geographic range AU - Sermons, Shannon M. AU - Burton, Michael G. AU - Rufty, Thomas W. T2 - WEED SCIENCE AB - The noxious weed Benghal dayflower has become a severely troublesome agricultural weed in Georgia in the southeastern Unite States, and there are indications that it is moving northward. Benghal dayflower is glyphosate tolerant and possesses a high degree of reproductive elasticity, making it a formidable threat in many crop systems. The purpose of these experiments was to develop the first temperature response profiles for Benghal dayflower, and use them to evaluate whether temperature might limit its northward invasion into North Carolina and adjacent states on the U.S. east coast. Experiments focused on vegetative and early reproductive growth, stages considered crucial for establishment and competitiveness. Exposure to a range of aerial temperatures revealed that Benghal dayflower growth and production of aerial and subterranean reproductive structures were maximized at 30 C, with sharp declines occurring at cooler temperatures. When exposed to differing root temperatures in hydroponics, with a constant aerial temperature, Benghal dayflower growth did not show the same cool temperature sensitivity, but reproductive performance declined when temperatures decreased below about 29 C. The root temperature responses of several other weed species known to thrive in the climate of this geographic area also were determined. Growth of sicklepod, hemp sesbania, and jimsonweed was more sensitive than Benghal dayflower to cool temperatures, whereas the growth response of velvetleaf was similar. Based on the comparison of the Benghal dayflower temperature responses in controlled environments to (1) seasonal air and soil temperatures in the field, and (2) the temperature responses of agronomic weeds known to thrive in the region, it is concluded that cool temperatures will not restrain the northward spread of Benghal dayflower into North Carolina. DA - 2008/// PY - 2008/// DO - 10.1614/WS-08-029.1 VL - 56 IS - 5 SP - 707-713 SN - 1550-2759 KW - tropical spiderwort KW - invasive species KW - weed invasion ER - TY - CONF TI - Nitrogen balance for a plantation forest drainage canal on the North Carolina coastal plain AU - Appelboom, T. W. AU - Chescheir, G. M. AU - Skaggs, R. W. AU - Gilliam, J. W. AU - Amatya, D. M. AB - Human alteration of the nitrogen cycle has led to increased riverine nitrogen loads, contributing to the eutrophication of lakes, streams, estuaries, and near-coastal oceans. These riverine nitrogen loads are usually less than the total nitrogen inputs to the system, indicating nitrogen removal during transport through the drainage network. A two-year monitoring study quantified the ammonium, nitrate, and organic-N inputs, outputs, and inferred in-stream processes responsible for nitrogen transformations and removal in a 1900 m reach of a drainage canal located in a managed pine plantation. Total nitrogen inputs to the canal section were 527.8 kg in 2001 and 1422.7 kg in 2002. Total nitrogen discharge at the outlet was 502 kg in 2001 and 1458 kg in 2002. The mass balance of nitrogen inputs and outputs indicated a loss of 25.8 kg (5.1%) of total nitrogen from the system in 2001, and a gain of 35.3 kg (2.4%) of total nitrogen to the system in 2002. Variability in the input and output estimates was high, especially for groundwater exchange. Different hydrologic and nitrogen inputs and outputs were identified and quantified, but measurement variability obscured any potential nitrogen removal from the system. C2 - 2008/// C3 - Transactions of the ASABE DA - 2008/// DO - 10.13031/2013.25239 VL - 51 SP - 1215-1233 M1 - 4 ER - TY - JOUR TI - Molecular characterization of maize inbreds with expired US plant variety protection AU - Nelson, Paul T. AU - Coles, Nathan D. AU - Holland, James B. AU - Bubeck, David M. AU - Smith, Stephen AU - Goodman, Major M. T2 - CROP SCIENCE AB - Maize inbred lines with expired Plant Variety Protection Act (PVPA) certificates are publicly available and potentially represent a new germplasm resource for many public and private breeding programs. However, accurate pedigree and genetic background information for ex‐PVPA maize inbreds is necessary if they are to be effectively utilized in breeding efforts. We have used single nucleotide polymorphism (SNP) markers to evaluate the relationships and population structure among 92 ex‐PVPA inbred lines in relation to 17 well‐known public inbreds. Based on unweighted pair group method with arithmetic mean clustering, principal components analysis, and model‐based clustering, we identified six primary genetic clusters represented by the prominent inbred lines B73, Mo17, PH207, A632, Oh43, and B37. We also determined the genetic background of ex‐PVPA inbreds with conflicting, ambiguous, or undisclosed pedigrees. We assessed genetic diversity across subsets of ex‐PVPA lines and concluded that the ex‐PVPA lines are no more diverse than the public set evaluated here. Additionally, all alleles present in the ex‐PVPA inbreds, for the 614 SNPs included in this study, are also found in public temperate maize germplasm. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.02.0092 VL - 48 IS - 5 SP - 1673-1685 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-54949106977&partnerID=MN8TOARS ER - TY - JOUR TI - Invasive forest pest surveillance: survey development and reliability AU - Coulston, John W. AU - Koch, Frank H. AU - Smith, William D. AU - Sapio, Frank J. T2 - CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE AB - Worldwide, a large number of potential pest species are introduced to locations outside their native ranges; under the best possible prevention scheme, some are likely to establish one or more localized populations. A comprehensive early detection and rapid-response protocol calls for surveillance to determine if a pest has invaded additional locations outside its original area of introduction. In this manuscript, we adapt and spatially extend a two-stage sampling technique to determine the required sample size to substantiate freedom from an invasive pest with a known level of certainty. The technique, derived from methods for sampling livestock herds for disease presence, accounts for the fact that pest activity may be low at a coarse spatial scale (i.e., among forested landscapes) but high at a fine scale (i.e., within a given forested landscape). We illustrate the utility of the approach by generating a national-scale survey based on a risk map for a hypothetical forest pest species threatening the United States. These techniques provide a repeatable, cost-effective, practical framework for developing broad-scale surveys to substantiate freedom from non-native invasive forest pests with known statistical power. DA - 2008/9// PY - 2008/9// DO - 10.1139/X08-076 VL - 38 IS - 9 SP - 2422-2433 SN - 0045-5067 ER - TY - JOUR TI - Heritability of oleic acid content in soybean seed oil and its genetic correlation with fatty acid and agronomic traits AU - Bachlava, Eleni AU - Burton, Joseph W. AU - Brownie, Cavell AU - Wang, Sanbao AU - Auclair, Jerome AU - Cardinal, Andrea J. T2 - CROP SCIENCE AB - Oleate content is important for the nutritional value and oxidative stability of soybean [ Glycine max (L.) Merr.] seed oil. Response to selection for higher oleate content depends on its heritability in breeding populations, and correlated responses of other fatty acid and agronomic traits to selection for oleate content depend on their genetic correlations with oleate. The objective of this study was to estimate the heritability of oleate content and to determine the correlation of oleate with other fatty acid and agronomic traits in three soybean populations segregating for major and minor oleate genes grown in multiple environments. One of the populations consisted of 721 lines, providing excellent precision for estimation of the genetic parameters. The results of this study indicated that heritability for oleate content was sufficiently high that early generation selection can be effective when practiced on unreplicated lines grown at a single environment. Significant negative correlations were observed between oleate and linoleate, oleate and linolenate, as well as oleate and palmitate in all three populations. Significant positive correlations were detected between palmitate and stearate in one population segregating for oleate genes and fap nc and fap1 alleles, which reduce palmitate content. In the same population we also observed a significant negative correlation between yield and oleate content, and positive correlations between yield and linoleate, and linolenate and palmitate contents. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.01.0049 VL - 48 IS - 5 SP - 1764-1772 SN - 1435-0653 ER - TY - JOUR TI - Geminivirus-Mediated Gene Silencing from Cotton Leaf Crumple Virus Is Enhanced by Low Temperature in Cotton AU - Tuttle, John R. AU - Idris, A.M. AU - Brown, Judith K. AU - Haigler, Candace H. AU - Robertson, Dominique T2 - Plant Physiology AB - A silencing vector for cotton (Gossypium hirsutum) was developed from the geminivirus Cotton leaf crumple virus (CLCrV). The CLCrV coat protein gene was replaced by up to 500 bp of DNA homologous to one of two endogenous genes, the magnesium chelatase subunit I gene (ChlI) or the phytoene desaturase gene (PDS). Cotyledons of cotton cultivar 'Deltapine 5415' bombarded with the modified viral vectors manifested chlorosis due to silencing of either ChlI or PDS in approximately 70% of inoculated plants after 2 to 3 weeks. Use of the green fluorescence protein gene showed that replication of viral DNA was restricted to vascular tissue and that the viral vector could transmit to leaves, roots, and the ovule integument from which fibers originate. Temperature had profound effects on vector DNA accumulation and the spread of endogenous gene silencing. Consistent with reports that silencing against viruses increases at higher temperatures, plants grown at a 30 degrees C/26 degrees C day/night cycle had a greater than 10-fold reduction in viral DNA accumulation compared to plants grown at 22 degrees C/18 degrees C. However, endogenous gene silencing decreased at 30 degrees C/26 degrees C. There was an approximately 7 d delay in the onset of gene silencing at 22 degrees C/18 degrees C, but silencing was extensive and persisted throughout the life of the plant. The extent of silencing in new growth could be increased or decreased by changing temperature regimes at various times following the onset of silencing. Our experiments establish the use of the CLCrV silencing vector to study gene function in cotton and show that temperature can have a major impact on the extent of geminivirus-induced gene silencing. DA - 2008/7/11/ PY - 2008/7/11/ DO - 10.1104/pp.108.123869 VL - 148 IS - 1 SP - 41-50 J2 - Plant Physiol. LA - en OP - SN - 0032-0889 1532-2548 UR - http://dx.doi.org/10.1104/pp.108.123869 DB - Crossref ER - TY - JOUR TI - Fate of nitrate in the capillary fringe and shallow groundwater in a drained sandy soil AU - Abit, Sergio M. AU - Amoozegar, Aziz AU - Vepraskas, Michael J. AU - Niewoehner, Christopher P. T2 - GEODERMA AB - It is commonly assumed that nitrate (NO3−) and other anions entering the soil move downward through the vadose zone, and then move horizontally in the groundwater. Recent laboratory studies, however, indicate that water movement and transport of pollutants can also take place in the capillary fringe (CF) above the water table (WT). This field study evaluated the fate of NO3− in the CF and shallow groundwater (SGW) for a sandy soil (Aeric Alaquod) with shallow water table. Ten L of a solution containing approximately 18 mmol L− 1 nitrate [2.66 g L− 1 Mg(NO3)2] and 77 mmol L− 1 bromide (9.12 g L− 1 KBr) were applied to the soil above the CF. The movement of both NO3− and Br− was monitored for 84 days by using tension lysimeters installed at depths between 45 and 105 cm at radial distances of 20, 60, 120, 220 and 320 cm from the application point. Nitrate and Br− plumes that entered the CF from the unsaturated zone moved horizontally in the CF until both species were partially carried into the groundwater by the fluctuating WT following rain events. Normalized concentrations of NO3−N and Br− remained comparable as they moved horizontally in the CF up to 320 cm from the tracer application spot. However, below the WT the detected normalized concentration of Br− was higher than that for NO3− indicating nitrate loss, perhaps due to denitrification. When monitoring subsurface NO3−, solely relying on collection of groundwater samples may lead to an underestimation of the extent of NO3− contamination and transport in the subsurface. DA - 2008/7/31/ PY - 2008/7/31/ DO - 10.1016/j.geoderma.2008.05.015 VL - 146 IS - 1-2 SP - 209-215 SN - 1872-6259 KW - capillary fringe KW - nitrate transport KW - denitrification KW - groundwater monitoring ER - TY - JOUR TI - Evaluation of a new, perforated heat flux plate design AU - Sauer, T. J. AU - Akinyemi, O. D. AU - Thery, P. AU - Heitman, J. L. AU - DeSutter, T. M. AU - Horton, R. T2 - INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER AB - Accurate measurement of heat flux is essential to optimize structural and process design and to improve understanding of energy transfer in natural systems. Laboratory and field experiments evaluated the performance of a new, perforated heat flux plate designed to reduce flow distortion for environmental applications. Laboratory tests involving dry and saturated sand showed that performance of the new CAPTEC plate is comparable to a solid, standard REBS plate. Very low thermal gradients may have however led to poor performance of the CAPTEC plate in saturated sand. Water infiltration and redistribution experiments using clayey and sandy soils showed an apparent reduced disruption of liquid water and vapour in the soil surrounding the CAPTEC plate as compared to solid Hukseflux and standard REBS plates. Surface area of REBS plate, though smaller than that of CAPTEC, did not lead to any significantly improved evaporation, due to perforations on CAPTEC plate. Field tests in a loam soil indicated that the CAPTEC plates were durable and produced daily total flux values within ~ 0.15 MJ m− 2 of independent estimates. DA - 2008/8// PY - 2008/8// DO - 10.1016/j.icheatmasstransfer.2008.03.012 VL - 35 IS - 7 SP - 800-804 SN - 0735-1933 KW - heat flux plate KW - heat flux density KW - field measurements KW - laboratory evaluation KW - porous media ER - TY - JOUR TI - Efficacy of residual and non-residual herbicides used in cotton production systems when applied with glyphosate, glufosinate, or MSMA AU - Price, Andrew J. AU - Koger, Clifford H. AU - Wilcut, John W. AU - Miller, Donnie AU - Santen, Edzard T2 - WEED TECHNOLOGY AB - Field experiments were conducted to evaluate weed control provided by glyphosate, glufosinate, and MSMA applied alone or in mixture with residual and nonresidual last application (LAYBY) herbicides. Herbicide treatments included glyphosate early postemergence (EPOST) alone or followed by glyphosate, glufosinate, or MSMA late-postemergence (LPOST) alone or tank-mixed with one of the following LAYBY herbicides: carfentrazone-ethyl at 0.3 kg ai/ha, diuron at 1.12 kg ai/ha, flumioxazin at 0.07 kg ai/ha, fluometuron at 1.12 kg ai/ha, lactofen at 0.84 kg ai/ha, linuron at 0.56 kg ai/ha, oxyfluorfen at 1.12 kg ai/ha, prometryn at 1.12 kg ai/ha, or prometryn + trifloxysulfuron at 1.12 kg ai/ha + 10 g ai/ha. Residual herbicides were also applied alone LPOST. Weeds evaluated included barnyardgrass, broadleaf signalgrass, coffee senna, entireleaf morningglory, hemp sesbania, ivyleaf morningglory, johnsongrass, large crabgrass, Palmer amaranth, pitted morningglory, prickly sida, redroot pigweed, sicklepod, smooth pigweed, spiny amaranth, and velvetleaf. Treatments containing MSMA provided lower average weed control compared to those containing glyphosate or glufosinate, and residual herbicides applied alone provided inadequate weed control compared to mixtures containing a nonresidual herbicide. Across 315 of 567 comparisons (55%), when a LAYBY herbicide was added, weed control increased. The most difficult to control weed species at all locations was pitted morningglory. Barnyardgrass and hemp sesbania at the Mississippi location and hemp sesbania at the Louisiana location were collectively difficult to control across all treatments as well. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-083.1 VL - 22 IS - 3 SP - 459-466 SN - 1550-2740 KW - LAYBY herbicide application KW - weed control ER - TY - JOUR TI - Effects of Postemergence and Postemergence-Directed Halosulfuron on Triploid Watermelon (Citrullus Lanatus) AU - Dittmar, Peter J. AU - Monks, David W. AU - Schultheis, Jonathan R. AU - Jennings, Katherine M. T2 - Weed Technology AB - Studies were conducted in 2006 at Clinton and Kinston, NC, to determine the influence of halosulfuron POST (over the crop plant) or POST-directed (to the crop) on growth and yield of transplanted ‘Precious Petite’ and ‘Tri-X-313’ triploid watermelon. Treatments included a nontreated control, 39 g/ha halosulfuron applied POST-directed to 25% of the plant (distal or proximal region), POST-directed to 50% of the plant (distal or proximal; Precious Petite only), and POST. Watermelon treated with halosulfuron displayed chlorotic leaves, shortened internodes, and increased stem splitting. Vines were longest in the nontreated control (Tri-X-313 = 146 cm, Precious Petite = 206 cm) but were shortest in the POST treatment (Tri-X-313 = 88 cm, Precious Petite = 77 cm). Halosulfuron POST to watermelon caused the greatest injury (Tri-X-313 = 64%, Precious Petite = 67%). Halosulfuron directed to 25 or 50% (distal or proximal) of the plant caused less injury than halosulfuron applied POST. Stem splitting was greatest when halosulfuron was applied to the proximal area of the stem compared with POST-directed distal or POST. Internode shortening was greatest in treatments where halosulfuron was applied to the distal region of the stem. However, Tri-X-313 in the POST-directed 25% distal treatment produced similar total and marketable fruit weight as the nontreated control at Clinton. Fruit number did not differ among treatments for either cultivar. At Kinston, Precious Petite nontreated control and POST-directed 25% distal end treatment had greater marketable fruit weight than the POST-directed 50% proximal and POST treatments. The current halosulfuron registration allows POST application between rows or PRE. Limiting halosulfuron contact to no more than 25% of the watermelon plant will likely improve crop tolerance. DA - 2008/9// PY - 2008/9// DO - 10.1614/WT-07-056.1 VL - 22 IS - 3 SP - 467-471 J2 - Weed technol. LA - en OP - SN - 0890-037X 1550-2740 UR - http://dx.doi.org/10.1614/wt-07-056.1 DB - Crossref KW - crop injury KW - directed spray KW - herbicide KW - sulfonylurea KW - nutsedge control ER - TY - JOUR TI - Effect of simulated rainfall on tall fescue (Lolium arundinaceum) control with glyphosate AU - Gannon, Travis W. AU - Yelverton, Fred H. T2 - WEED TECHNOLOGY AB - Field experiments were conducted to determine the effect of simulated rainfall after glyphosate application on tall fescue control. Three glyphosate formulations, three simulated rainfall amounts, two application rates, and three rain-free periods were evaluated. Glyphosate formulations evaluated included Roundup Original ® , Roundup Pro ® , and Roundup ProDry ® . Herbicide drying periods, or rain-free intervals, included 15, 30, or 60 min. Simulated rainfall amounts were 0, 0.25, or 0.64 cm. Application rates of glyphosate were 3.4 or 6.7 kg ae/ha. Averaged across glyphosate formulation and simulated rainfall amount, excellent (≥ 90%) tall fescue control was observed when no simulated rainfall occurred within 60 min after application, whereas good (≥ 80%) tall fescue control was observed when 30 rain-free min were provided. Although current glyphosate labels are vague about rainfastness, these data indicate that critical rain-free periods may be as short as 30 min when higher application rates are used. DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-158.1 VL - 22 IS - 3 SP - 553-557 SN - 1550-2740 ER - TY - JOUR TI - Dietary Chemical Composition, Plasma Metabolites and Hormones in Range Goats AU - Juarez-Reyes, Arturo S. AU - Nevarez-Carrasco, Gumaro AU - Cerrillo-Soto, Maria A. AU - Murillo-Ortiz, Manuel AU - Luginbuhl, Jean-Marie AU - Bernal-Barragan, Hugo AU - Ramirez, Roque G. T2 - JOURNAL OF APPLIED ANIMAL RESEARCH AB - Abstract Juárez-Reyes, A.S., Nevarez-Carrasco, G., Cerrillo-Soto, M.A., Murillo-Ortiz, M., Luginbuhl, J-M., Bernal-Barragán, H. and Ramírez, R.G. 2008. Dietary chemical composition, plasma metabolites and hormones in range goats. J. Appl. Anim. Res, 34: 81–86. The objective of this study was to determine the monthly chemical composition of the diet consumed by range goats and plasma concentrations of glucose, urea, non-esterified fatty acids (NEFA), luteinizing hormone (LH), growth hormone (GH), insulin and progesterone (P4) during lactation (January-June). Three esophageally-cannulated female goats and twelve intact female goats (38±1.7 kg BW) were used to obtain extrusa and blood samples, respectively. Body weight decreased (P<0.05) by 12.5% during the period from January to May, whereas, in June goats lost 250 g d−1. There was a fall in nutrient density during May and June. With the exception of progesterone (0.1–0.6 ng ml−1), LH (7.1–11.0), GH (22.8–30) and insulin (0.6–1.8) increased (P<0.05) as lactation period progressed. It is concluded that plasma metabolite concentrations suggested that an energy supplementation schedule might be necessary during the early lactation period of goats. In addition, if harsh climatic conditions appear at the end of lactation, an increment of 70% in their energy maintenance requirements might be considered to avoid weight losses and to improve body condition of goats prior to breeding season. DA - 2008/9// PY - 2008/9// DO - 10.1080/09712119.2008.9706945 VL - 34 IS - 1 SP - 81-86 SN - 0974-1844 KW - Chemical composition KW - diet KW - blood metabolites KW - lactation KW - plasma hormones KW - range goats ER - TY - JOUR TI - Response of selected aquatic invasive weeds to Flumioxazin and Carfentrazone-ethyl AU - Richardson, R. J. AU - Roten, R. L. AU - West, A. M. AU - True, S. L. AU - Gardner, A. P. T2 - Journal of Aquatic Plant Management DA - 2008/// PY - 2008/// VL - 46 SP - 154-158 ER - TY - JOUR TI - Genetic variation and environmental effects on beta-conglycinin and glycinin content in Brazilian soybean cultivars AU - Carrao-Panizzi, Mercedes Concordia AU - Kwanyuen, Prachuab AU - Erhan, Sevim Zeynep AU - Negrao Lopes, Ivani de Oliveira T2 - PESQUISA AGROPECUARIA BRASILEIRA AB - The objective of this work was to determine genetic and environmental effects on beta-conglycinin and glycinin content in Brazilian soybean cultivars. The concentrations of these protein fractions were analyzed by scanning densitometry after electrophoresis, in 90 Brazilian soybean cultivars sown in Ponta Grossa, PR, in 2001. The effects of the sowing location were determined in the cultivar MG/BR 46 (Conquista), sown in 16 locations of Goiás and Minas Gerais states (Central Brazil), and in the cultivar IAS 5, sown in 12 locations of Paraná and São Paulo states (Southern Brazil), in 2002 soybean season. A significant variability for beta-conglycinin (7S) and glycinin (11S) protein fractions ratio was observed among the 90 Brazilian soybean cultivars. 'MS/BRS 169' (Bacuri) and 'BR-8' (Pelotas) presented the highest and the lowest 11S/7S ratios (2.76 and 1.17, respectively). Beta-conglycinin protein fractions presented more variability than glycinin protein fractions. Grouping test classified 7S proteins in seven groups, 11S proteins in four groups, and protein fraction ratios (11S/7S) in nine groups. Significant effect of sowing locations was also observed on protein fractions contents. There is a good possibility of breeding for individual protein fractions, and their subunits, without affecting protein content. DA - 2008/9// PY - 2008/9// DO - 10.1590/S0100-204X2008000900002 VL - 43 IS - 9 SP - 1105-1114 SN - 1678-3921 KW - eletrophoresis KW - nutraceutic properties KW - protein fractions KW - seed KW - sowing location ER - TY - JOUR TI - Sensible heat measurements indicating depth and magnitude of subsurface soil water evaporation AU - Heitman, J. L. AU - Xiao, X. AU - Horton, R. AU - Sauer, T. J. T2 - WATER RESOURCES RESEARCH AB - Most measurement approaches for determining evaporation assume that the latent heat flux originates from the soil surface. Here, a new method is described for determining in situ soil water evaporation dynamics from fine‐scale measurements of soil temperature and thermal properties with heat pulse sensors. A sensible heat balance is computed using soil heat flux density at two depths and change in sensible heat storage in between; the sensible heat balance residual is attributed to latent heat from evaporation of soil water. Comparisons between near‐surface soil heat flux density and Bowen ratio energy balance measurements suggest that evaporation originates below the soil surface several days after rainfall. The sensible heat balance accounts for this evaporation dynamic in millimeter‐scale depth increments within the soil. Comparisons of sensible heat balance daily evaporation estimates to Bowen ratio and mass balance estimates indicate strong agreement ( r 2 = 0.96, root‐mean‐square error = 0.20 mm). Potential applications of this technique include location of the depth and magnitude of subsurface evaporation fluxes and estimation of stage 2–3 daily evaporation without requirements for large fetch. These applications represent new contributions to vadose zone hydrology. DA - 2008/10/18/ PY - 2008/10/18/ DO - 10.1029/2008wr006961 VL - 44 SP - SN - 0043-1397 ER - TY - JOUR TI - Effects of floral resources on fitness of the parasitoids Trichogramma exiguum (Hymenoptera: Trichogrammatidae) and Cotesia congregata (Hymenoptera: Braconidae) AU - Witting-Bissinger, B. E. AU - Orr, D. B. AU - Linker, H. M. T2 - BIOLOGICAL CONTROL AB - This study was conducted to determine if floral resources enhanced longevity and fecundity of the egg parasitoid Trichogramma exiguum Pinto & Platner and longevity of the larval parasitoid Cotesia congregata (Say). Newly eclosed (⩽12 h) female wasps were provisioned with fennel (Foeniculum vulgare P. Mill.) or buckwheat (Fagopyrum esculentum Moench) flowers or one of two controls: honey or water. Wasps were monitored daily until all had died. Daily egg production by T. exiguum was monitored using Ephestia kuehniella Keller egg cards. Longevity of both T. exiguum (6.7 d) and C. congregata (5.1 d) provided buckwheat flowers was increased approximately 8.5-fold compared with wasps provided only water. Buckwheat-provisioned T. exiguum exhibited 2-fold greater longevity than those provided fennel. Longevity of C. congregata provisioned with fennel and honey was not statistically different. Water-provisioned T. exiguum and C. congregata exhibited the shortest longevity (0.8 and 0.6 d, respectively). Total fecundity was 6.3-fold greater in T. exiguum provisioned with buckwheat and 2.3-fold greater in T. exiguum provisioned with fennel than in water controls. Average female to male ratio of progeny over the lifetime of each female was significantly greatest in T. exiguum provisioned with water alone, likely because of sperm depletion in wasps exhibiting greater longevity. Total mean number of female offspring produced was significantly greatest in T. exiguum provided honey or buckwheat flowers although no difference in total female offspring were observed between adults provisioned with buckwheat or fennel flowers. Our results show that provisioning T. exiguum with honey and buckwheat flowers resulted in greater longevity, total fecundity, and lifetime production of female offspring than water alone. Buckwheat flowers also lead to greater longevity in C. congregata. DA - 2008/11// PY - 2008/11// DO - 10.1016/j.biocontrol.2008.07.013 VL - 47 IS - 2 SP - 180-186 SN - 1090-2112 KW - Cotesia congregata KW - Trichogramma exiguum KW - Beneficial insect habitat KW - Biological control ER - TY - JOUR TI - A new method for isolating large quantities of Arabidopsis trichomes for transcriptome, cell wall and other types of analyses AU - Marks, M. David AU - Betancur, Lissete AU - Gilding, Edward AU - Chen, Fang AU - Bauer, Stefan AU - Wenger, Jonathan P. AU - Dixon, Richard A. AU - Haigler, Candace H. T2 - PLANT JOURNAL AB - A new procedure has been developed for the isolation of wild-type and mutant Arabidopsis trichomes. The isolated trichomes maintained enzymatic activity and were used for DNA, protein, and RNA isolation. The RNA was used to generate probes suitable for Affymetrix analysis. The validity of the Affymetrix results was confirmed by quantitative PCR analysis on a subset of genes that are preferentially expressed in trichomes or leaves. Sufficient quantities of trichomes were isolated to probe the biochemical nature of trichome cell walls. These analyses provide evidence for the presence of lignin in Arabidopsis trichome cell walls. The monosaccharide analysis and positive staining with ruthenium red indicates that the walls also contain a large portion of pectin. The 2.23-fold ratio of pectin-related sugars compared with potential cellulosic glucose suggests that the polysaccharides of the trichome cell walls are more like those of typical primary walls even though the wall becomes quite thick. Overall, these analyses open the door to using the Arabidopsis trichome cell wall as an excellent model to probe various questions concerning plant cell wall biosynthesis. DA - 2008/11// PY - 2008/11// DO - 10.1111/j.1365-313X.2008.03611.x VL - 56 IS - 3 SP - 483-492 SN - 0960-7412 KW - trichome isolation KW - trichome cell wall KW - trichome gene expression KW - lignin KW - pectin ER - TY - JOUR TI - Sequential transphosphorylation of the BRI1/BAK1 receptor kinase complex impacts early events in brassinosteroid signaling AU - Wang, Xiaofeng AU - Kota, Uma AU - He, Kai AU - Blackburn, Kevin AU - Li, Jia AU - Goshe, Michael B. AU - Huber, Steven C. AU - Clouse, Steven D. T2 - DEVELOPMENTAL CELL AB - Brassinosteroids (BRs) regulate plant development through a signal transduction pathway involving the BRI1 and BAK1 transmembrane receptor kinases. The detailed molecular mechanisms of phosphorylation, kinase activation, and oligomerization of the BRI1/BAK1 complex in response to BRs are uncertain. We demonstrate that BR-dependent activation of BRI1 precedes association with BAK1 in planta, and that BRI1 positively regulates BAK1 phosphorylation levels in vivo. BRI1 transphosphorylates BAK1 in vitro on specific kinase-domain residues critical for BAK1 function. BAK1 also transphosphorylates BRI1, thereby quantitatively increasing BRI1 kinase activity toward a specific substrate. We propose a sequential transphosphorylation model in which BRI1 controls signaling specificity by direct BR binding followed by substrate phosphorylation. The coreceptor BAK1 is then activated by BRI1-dependent transphosphorylation and subsequently enhances signaling output through reciprocal BRI1 transphosphorylation. This model suggests both conservation and distinct differences between the molecular mechanisms regulating phosphorylation-dependent kinase activation in plant and animal receptor kinases. DA - 2008/8/12/ PY - 2008/8/12/ DO - 10.1016/j.devcel.2008.06.011 VL - 15 IS - 2 SP - 220-235 SN - 1534-5807 ER - TY - JOUR TI - A test of coupled soil heat and water transfer prediction under transient boundary temperatures AU - Heitman, J. L. AU - Horton, R. AU - Ren, T. AU - Nassar, I. N. AU - Davis, D. D. T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Diffusion‐based coupled soil heat and water transfer theory includes capability to describe transient behavior. Unfortunately, laboratory tests of theory typically include a single initial water content distribution with a single set of boundary conditions, rather than providing a set of experimental conditions with a range of measurements for comparison with predictions. Agreement between theory and measurements can result from calibration, but this provides an incomplete test of theory. The objective of this work was to test diffusion‐based coupled heat and water transfer theory by comparing theory‐based predictions with measured transient temperature and water content distributions. Data from a single boundary condition were used for calibration of each of two soils, silt loam and sand. Subsequent testing was performed at additional boundary and initial conditions using measurements from the same soil. Results indicate that the theory can be calibrated for a single boundary condition with adjustment of soil saturated hydraulic conductivity and/or the vapor enhancement factor, which adjust the liquid and vapor fluxes, respectively. For silt loam, calibration reduced Root Mean Square Error (RMSE) by 67 and 18% for water content and temperature distributions, respectively. For sand, RMSE was reduced by 14 and 46% for water content and temperature, respectively. Using this calibration, there was agreement between calculated and measured distributions for additional boundary and initial conditions with RMSE ≤ 0.03 m 3 m −3 and 1.28°C for water content and temperature distributions, respectively. However, when the boundary temperature gradient was instantly reversed, noticeable differences occurred between measured and calculated patterns of heat and moisture redistribution. The theory described observations well when boundary temperature conditions were changed gradually, but results suggested a need for further development of coupled heat and water transfer theory combined with testing under transient conditions to make improvements in the description of transfer mechanisms. DA - 2008/// PY - 2008/// DO - 10.2136/sssaj2007.0234 VL - 72 IS - 5 SP - 1197-1207 SN - 1435-0661 ER - TY - JOUR TI - Wheat woes AU - Brown-Guedira, G. T2 - Scientist DA - 2008/// PY - 2008/// VL - 22 IS - 9 SP - 60-60 ER - TY - JOUR TI - Use of transferable Nicotiana tabacum L. microsatellite markers for investigating genetic diversity in the genus Nicotiana AU - Moon, H. S. AU - Nicholson, J. S. AU - Lewis, R. S. T2 - GENOME AB - The recent development of microsatellite markers for tobacco, Nicotiana tabacum L., may be valuable for genetic studies within the genus Nicotiana. The first objective was to evaluate transferability of 100 N. tabacum microsatellite primer combinations to 5 diploid species closely related to tobacco. The number of primer combinations that amplified scorable bands in these species ranged from 42 to 56. Additional objectives were to assess levels of genetic diversity amongst available accessions of diploid relatives closely related to tobacco (species of sections Sylvestres and Tomentosae), and to evaluate the efficacy of microsatellite markers for establishing species relationships in comparison with existing phylogenetic reconstructions. A subset of 46 primer combinations was therefore used to genotype 3 synthetic tobaccos and an expanded collection of 51 Nicotiana accessions representing 15 species. The average genetic similarity for 7 diverse accessions of tobacco was greater than the average similarity for N. otophora accessions, but lower than the average genetic similarities for N. sylvestris, N. tomentosa, N. kawakamii, and N. tomentosiformis accessions. A microsatellite-based phylogenetic tree was largely congruent with taxonomic representations based on morphological, cytological, and molecular observations. Results will be useful for selection of parents for creation of diploid mapping populations and for germplasm introgression activities. DA - 2008/8// PY - 2008/8// DO - 10.1139/G08-039 VL - 51 IS - 8 SP - 547-559 SN - 0831-2796 KW - microsatellite markers KW - tobacco KW - Nicotiana tabacum KW - genetic diversity ER - TY - JOUR TI - Uncertainties in the current knowledge of some atmospheric trace gases associated with US agriculture: A review AU - Krupa, Sagar AU - Booker, Fitzerald AU - Bowersox, Van AU - Lehmann, Chris Topher AU - Grantz, David T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - Approximately 80 different crop species are grown in the United States in widely differing geographic areas, climatic and edaphic conditions, and management practices. Although the majority of cultivated acreage in the United States is planted with only about 10 primary crops, uncertainties associated with trace gas emissions arise from: (1) limited data availability, (2) inaccurate estimates because of large temporal and spatial variability in trace gas composition and magnitude of trace gas emissions from agricultural activities, (3) differing characteristics of pollutant emissions from highly dispersed animal feed-lots, and (4) limited understanding of the emissions of semi-volatile organic compounds (SVOCs) associated with agriculture. Although emission issues are of concern, so also is atmospheric deposition to cropping systems, including wet and dry nitrogen, minerals, and organic compounds. These can have feedback effects on trace gas emissions. Overall, the many gaps in our understanding of these aspects of agricultural systems deserve serious attention. DA - 2008/8// PY - 2008/8// DO - 10.3155/1047-3289.58.8.986 VL - 58 IS - 8 SP - 986-993 SN - 1047-3289 ER - TY - JOUR TI - Bartonella sp bacteremia in patients with neurological and neurocognitive dysfunction AU - Breitschwerdt, E. B. AU - Maggi, R. G. AU - Nicholson, W. L. AU - Cherry, N. A. AU - Woods, C. W. T2 - JOURNAL OF CLINICAL MICROBIOLOGY AB - We detected infection with a Bartonella species (B. henselae or B. vinsonii subsp. berkhoffii) in blood samples from six immunocompetent patients who presented with a chronic neurological or neurocognitive syndrome including seizures, ataxia, memory loss, and/or tremors. Each of these patients had substantial animal contact or recent arthropod exposure as a potential risk factor for Bartonella infection. Additional studies should be performed to clarify the potential role of Bartonella spp. as a cause of chronic neurological and neurocognitive dysfunction. DA - 2008/9// PY - 2008/9// DO - 10.1128/JCM.00832-08 VL - 46 IS - 9 SP - 2856-2861 SN - 1098-660X ER - TY - JOUR TI - Water flow from trenches through different soils AU - Amoozegar, Aziz AU - Niewoehner, C. AU - Lindbo, D. T2 - Journal of Hydrologic Engineering AB - It is often assumed that soils are homogeneous when designing septic systems or modeling wastewater flow from their trenches. The main objective of this study was to assess water infiltration and movement from the trenches similar to the ones commonly used for on-site wastewater dispersal by septic systems. Four separate experiments, each using a small drainfield with four parallel trenches, were conducted at three sites with different soils. In two experiments the trenches were in the coarse-textured soil above a clayey Bt horizon. In the other two experiments the trenches were in the Bt horizon. For each experiment, 50L of a solution containing potassium bromide and brilliant blue FCF (as a tracer dye) were applied once a day to each trench for 14 or 15 days. A sampling pit was dug perpendicular to the trenches after the tracer solution application, and the distribution of the tracer dye and Br− around the trenches on the two walls of the pit were assessed. Tracer solution infiltration from the trenches was not uniform in any of the experiments. Water flow in the Bt horizon was mainly through macropores. Further, water containing Br− and dye moved a substantial distance from the trenches through macropores when trenches were installed in the Bt horizon. When trenches were installed in the coarse-textured soil above the Bt horizon, most of the tracer solution moved away laterally from the drainfield through the zone above the Bt horizon. Overall, the results indicate that soil morphological properties and soil horizonations, as well as the nature of water movement from trenches must be considered when modeling water flow from septic system trenches or when designing septic system drainfields. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)1084-0699(2008)13:8(655) VL - 13 IS - 8 SP - 655–664 ER - TY - JOUR TI - Three-component phase behavior of the sclareol-ethyl lactate-carbon dioxide system for GAS applications AU - Tombokan, Xenia C. AU - Aguda, Remil M. AU - Danehower, David A. AU - Kilpatrick, Peter K. AU - Carbonell, Ruben G. T2 - JOURNAL OF SUPERCRITICAL FLUIDS AB - This paper focuses on the extraction of sclareol from the leaves of Salvia sclarea Lamiaceae, more commonly known as Clary sage. The process involves the extraction of sclareol using a CO2-soluble GRAS solvent such as ethyl lactate, followed by GAS anti-solvent precipitation from ethyl lactate solution with carbon dioxide. The three-component phase behavior of the sclareol–ethyl lactate–CO2 system at various pressures has been determined and indicates a slight cybotactic effect. The ability of thermodynamic models to predict the complex three-component phase behavior of this system is discussed, together with the implications of the thermodynamic behavior of the system on process design. DA - 2008/6// PY - 2008/6// DO - 10.1016/j.supflu.2007.12.007 VL - 45 IS - 2 SP - 146-155 SN - 0896-8446 KW - GAS KW - GRAS solvents KW - nutraceuticals KW - sclareol KW - extraction KW - precipitation ER - TY - JOUR TI - Successful cloning of the Yucatan minipig using commercial/occidental breeds as oocyte donors and embryo recipients AU - Estrada, Jose L. AU - Collins, Bruce AU - York, Abby AU - Bischoff, Steve AU - Sommer, Jeff AU - Tsai, Shengdar AU - Petters, Robert M. AU - Piedrahita, Jorge A. T2 - CLONING AND STEM CELLS AB - The widespread application of porcine SCNT to biomedical research is being hampered by the large adult size (300–600 lbs) of the commercial breeds commonly used for SCNT. The Yucatan minipig, in contrast, has an adult weight of 140–150 lbs and a long history of utility in biomedical research. In order to combine the wide availability of commercial swine with the biomedical value of the Yucatan minipig, we utilized SCNT using the Yucatan as nuclear donors and commercial swine as both oocyte donors and recipients. Of six recipient gilts receiving 631 SCNT embryos, three went to term and delivered seven piglets, four of which survived to adulthood. Additionally, we obtained fetal fibroblasts from a cloned Yucatan and used them for a second round of SCNT. Of three recipients receiving 315 reconstructed embryos, one went to term and delivered three piglets, one of which survived to adulthood. Both microsatellite and D-loop sequence analysis confirmed that all of the piglets generated were nuclear-mitochondrial hybrids carrying Yucatan nuclear DNA and commercial breed mitochondrial DNA. This report shows that it is possible to produce viable Yucatan SCNT clones and opens up the possibility of developing valuable biomedical models in this porcine breed. DA - 2008/6// PY - 2008/6// DO - 10.1089/clo.2008.0005 VL - 10 IS - 2 SP - 287-296 SN - 1536-2302 ER - TY - JOUR TI - Soybean molecular linkage group B1 corresponds to classical linkage group 16 based on map location of the lf(2) gene AU - Seversike, Thomas M. AU - Ray, Jeffery D. AU - Shultz, Jeffry L. AU - Purcell, Larry C. T2 - THEORETICAL AND APPLIED GENETICS DA - 2008/7// PY - 2008/7// DO - 10.1007/s00122-008-0759-6 VL - 117 IS - 2 SP - 143-147 SN - 0040-5752 ER - TY - JOUR TI - Palmer amaranth and large crabgrass growth with plasticulture-grown bell pepper AU - Norsworthy, Jason K. AU - Oliveira, Marcos J. AU - Jha, Prashant AU - Malik, Mayank AU - Buckelew, Juliana K. AU - Jennings, Katherine M. AU - Monks, David W. T2 - WEED TECHNOLOGY AB - Field experiments were conducted in 2004 and 2005 at Clemson, SC, and in 2004 at Clinton, NC, to quantify Palmer amaranth and large crabgrass growth and interference with plasticulture-grown bell pepper over multiple environments and develop models which can be used on a regional basis to effectively time removal of these weeds. Experiments at both locations consisted of an early and a late spring planting, with the crop and weeds planted alone and in combination. Daily maximum and minimum air temperatures were used to calculate growing degree days (GDD, base 10 C) accumulated following bell pepper transplanting and weed emergence. Linear and nonlinear empirical models were used to describe ht, canopy width, and biomass production as a function of accumulated GDD. Palmer amaranth reduced bell pepper fruit set as early as 6 wk after transplanting (WATP) (648 GDD), whereas large crabgrass did not significantly reduce fruit set until 8 WATP (864 GDD). Using the developed models and assuming Palmer amaranth and large crabgrass emergence on the day of bell pepper transplanting, Palmer amaranth was predicted to be the same ht as bell pepper at 287 GDD (20 cm tall) and large crabgrass the same ht as bell pepper at 580 GDD (34 cm tall).Nomenclature: Large crabgrass, Digitaria sanguinalis (L.) Scop. DIGSA, Palmer amaranth, Amaranthus palmeri S. Wats. AMAPA, bell pepper, Capsicum annuum L. ‘Heritage’ DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-043.1 VL - 22 IS - 2 SP - 296-302 SN - 1550-2740 KW - growing degree days KW - growth rate KW - minor use crop KW - weed interference ER - TY - JOUR TI - Intensive management affects composition of betaproteobacterial ammonia oxidizers in turfgrass systems AU - Dell, Emily A. AU - Bowman, Daniel AU - Rufty, Thomas AU - Shi, Wei T2 - MICROBIAL ECOLOGY DA - 2008/7// PY - 2008/7// DO - 10.1007/s00248-007-9335-x VL - 56 IS - 1 SP - 178-190 SN - 1432-184X ER - TY - JOUR TI - Glufosinate-resistant corn interference in glufosinate-resistant cotton AU - Clewis, Scott B. AU - Thomas, Walter E. AU - Everman, Wesley J. AU - Witcut, John W. T2 - WEED TECHNOLOGY AB - Studies were conducted at three locations in North Carolina in 2004 to evaluate density-dependent effects of glufosinate-resistant (GUR) corn on GUR cotton growth and lint yield. GUR corn was taller than GUR cotton as early as 11 d after planting, depending on location. A GUR corn density of 5.25 plant/m of crop row reduced late-season cotton height by 38, 43, and 43% at Clayton, Lewiston-Woodville, and Rocky Mount, NC, respectively, compared with weed-free cotton height. GUR corn dry biomass per meter of crop row and GUR corn seed biomass per meter of crop row decreased linearly with increasing GUR corn density at all locations. The relationship between GUR corn density and GUR cotton yield loss was described by the rectangular hyperbola model with the asymptote (a) constrained to 100% maximum yield loss. The estimated coefficient i (yield loss per unit density as density approaches zero) was 7, 5, and 6 at Clayton, Lewiston-Woodville, and Rocky Mount, respectively. Percentage of GUR cotton lint yield loss increased 4, 5, and 8 percentage points at Clayton, Lewiston-Woodville, and Rocky Mount, respectively, with each 500 g increase in weed biomass/m of crop row. The examined GUR corn densities had a significant effect on cotton yield but not as significant as many other problematic grass and broadleaf weeds.Nomenclature: Glufosinate, corn, Zea mays L. ‘Pioneer 34A55LL’ ZEAMX, cotton, Gossypium hirsutum L., ‘FM 958LL’ DA - 2008/// PY - 2008/// DO - 10.1614/WT-07-085.1 VL - 22 IS - 2 SP - 211-216 SN - 1550-2740 KW - competition KW - economic threshold KW - models KW - weed biomass KW - weed density KW - plant height ER - TY - JOUR TI - Runoff water quality from manured riparian grasslands with contrasting drainage and simulated grazing pressure AU - Butler, David M. AU - Ranells, Noah N. AU - Franklin, Dorcas H. AU - Poore, Matthew H. AU - Green, James T., Jr. T2 - AGRICULTURE ECOSYSTEMS & ENVIRONMENT AB - Globally,management ofgrazedriparian areasiscriticallyimportanttoagriculturalsustainabilityandenvironmentalquality.However,the potential impacts of riparian grazing management on water quality are not well-documented, particularly in the southeastern USA. The objective of this work was to determine sediment and nutrient export under simulated rainfall from poorly drained and well-drained riparian soils where heavy or light grazing pressure by cattle was simulated. Plots were established on stands of existing vegetation to create grazing pressure treatments of (a) light-use (full ground cover, uncompacted), and with stands modified to establish (b) heavy-use (bare ground, compacted) treatments. Vegetation on poorly drained soils consisted of several typical wetland species (e.g., Pontederia cordata L., Juncus coriaceus Mackenzie) in the southeastern USA, whereas mixed tall fescue (Festuca arundinacea Schreb.)‐dallisgrass (Paspalum dilatatum Poir.) stands were the dominant vegetation on well-drained soils. Runoff volumewas generally greater from heavy-use than from light-use for poorly drained soils and for well-drained soils. Greater runoff volume was also observed from poorly drained soils compared to well-drained soils for both light-use and for heavy-use treatments. Light-use plots were remarkably effective at minimizing export of total suspended solids (TSS)onboth soils (<30 kg ha � 1 ). Mean total Kjeldahl P(TKP) exportwas fourfold greater from heavy-useplots than from light-use plots on both soils. While export of nitrate-nitrogen (NO3-N) was unaffected by grazing pressure and soil drainage, mean ammonium-nitrogen (NH4N) and total N (TN) export from poorly drained heavy-use plots was greater than fivefold that from well-drained light-use plots. Results indicate that livestock heavy-use areas in the riparian zone may export substantial TSS and nutrients, especially on poorly drained soils. However, when full ground cover is maintained on well-drained soils, TSS and nutrient losses may be limited. # 2008 Elsevier B.V. All rights reserved. DA - 2008/7// PY - 2008/7// DO - 10.1016/j.agee.2008.02.004 VL - 126 IS - 3-4 SP - 250-260 SN - 1873-2305 KW - grazing management KW - nitrogen KW - phosphorus KW - riparian KW - runoff KW - soil compaction KW - drainage ER - TY - JOUR TI - Root penetration through a high bulk density soil layer: differential response of a crop and weed species AU - Place, George AU - Bowman, Daniel AU - Burton, Michael AU - Rutty, Thomas T2 - PLANT AND SOIL DA - 2008/6// PY - 2008/6// DO - 10.1007/s11104-008-9594-4 VL - 307 IS - 1-2 SP - 179-190 SN - 1573-5036 KW - hard pan KW - root mechanical impedance KW - root plasticity KW - plant competition KW - 15N acquisition KW - below ground competition ER - TY - JOUR TI - Response of corn and cotton to starter phosphorus on soils testing very high in phosphorus AU - Cahill, Sheri AU - Johnson, Amy AU - Osmond, Deanna AU - Hardy, David T2 - AGRONOMY JOURNAL AB - Phosphorus from agricultural lands poses a problem in water resources. In 2003, more than 48% of soil samples submitted to the North Carolina Department of Agriculture and Consumer Services (NCDA&CS) soil testing laboratory tested very high in soil P (>120 mg dm −3 P). As soil test P increases, off‐site P loss increases, through erosion, soluble P runoff, or leaching. On soils testing above high soil test P (60–120 mg dm −3 P), studies from the northeast and midwest United States demonstrate that no corn ( Zea mays L.) or cotton ( Gossypium spp.) yield response from additional fertilizer is expected. However, there have been limited studies on the effects of starter‐P fertilizer on soils with very high P status in North Carolina and the southeast. Therefore, we undertook a study in the three physiographic regions (coastal plain, piedmont, and mountains) of North Carolina to determine if the use of starter‐P fertilizer would affect the growth of corn and cotton on soils having very high soil test P. Treatments were starter N and P, and starter N only. Treatment differences were not observed for corn, while the N‐only treatment had greater tissue N than the N‐ and P‐starter treatment in Piedmont cotton. Additionally, the use of only starter‐N is typically more cost effective than using both N and P starter fertilizer. For production, environmental, and economic reasons, starter‐P fertilizer is not warranted on North Carolina fields with very high soil test P values. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2007.0202 VL - 100 IS - 3 SP - 537-542 SN - 0002-1962 ER - TY - JOUR TI - Inferential model estimates of ammonia dry deposition in the vicinity of a swine production facility AU - Walker, John AU - Spence, Porche' AU - Kimbrough, Sue AU - Robarge, Wayne T2 - ATMOSPHERIC ENVIRONMENT AB - This project investigates NH3 dry deposition around a commercial swine production facility in eastern North Carolina. Passive diffusion-tube samplers were used to measure weekly integrated NH3 concentrations at 22 locations along horizontal gradients from the barn/lagoon emissions complex (source) out to a distance of 700 m. A two-layer canopy compensation point model was used to predict bi-directional NH3 exchange within a 500 m circular buffer surrounding the source. The model takes into account differences in soil and vegetation emission potential, as well as canopy physical characteristics, among three primary surfaces surrounding the site: forest, crops spray fertilized with swine waste, and other fertilized crops. Between June 2003 and July 2005, mean observed NH3 concentrations ranged from 169.0 μg NH3 m−3 at a distance of 10 m from the source to 7.1 and 13.0 μg NH3 m−3 at 612 and 698 m in the predominant upwind and downwind directions, respectively. Median predicted dry deposition rates ranged from 145 kg NH3–N ha−1 yr−1 at 10 m from the source to 16 kg NH3–N ha−1 yr−1 at 500 m, which is ≈3.5× wet deposition of NH4+–N. Assuming a steady-state emission factor of 7.0 kg NH3 animal−1 yr−1 and a median population of 4900 animals, NH3 dry deposition over the nearest 500 m from the barn/lagoon complex accounted for 10.4% (3567 kg NH3) of annual emissions (34,300 kg NH3). A model sensitivity analysis shows that predicted deposition rates are more sensitive to assumptions regarding cuticular uptake relative to soil and vegetation emission potentials. DA - 2008/4// PY - 2008/4// DO - 10.1016/j.atmosenv.2007.06.004 VL - 42 IS - 14 SP - 3407-3418 SN - 1873-2844 KW - ammonia KW - bi-directional flux KW - compensation point KW - dry deposition KW - resistance model ER - TY - JOUR TI - Gene expression enhancement mediated by the 5 ' UTR intron of the rice rubi3 gene varied remarkably among tissues in transgenic rice plants AU - Lu, Jianli AU - Sivamani, Elumalai AU - Azhakanandam, Kasi AU - Samadder, Partha AU - Li, Xianggan AU - Qu, Rongda T2 - MOLECULAR GENETICS AND GENOMICS DA - 2008/6// PY - 2008/6// DO - 10.1007/s00438-008-0333-6 VL - 279 IS - 6 SP - 563-572 SN - 1617-4615 KW - IME KW - intron KW - rubi3 gene promoter KW - transgenic rice KW - translation ER - TY - JOUR TI - Evaluating inorganic nitrogen and rye-crimson clover mixture fertilization of spring broccoli and lettuce by (15)Nitrogen tracing and mass balance AU - Holness, Rickie L. AU - Reddy, Muchha R. AU - Crozier, Carl R. AU - Niedziela, Carl E., Jr. T2 - JOURNAL OF PLANT NUTRITION AB - ABSTRACT Broccoli (Brassica oleraceaL. var. italica) and lettuce (Latuca sativaL.) were grown under greenhouse conditions with nitrogen (N) from a cover crop mixture of rye (Secale cerealeL.) and crimson clover (Trifolium incarnatumL.) and ammonium nitrate (NH4NO3). Individual cover crop species were produced with non-enriched or enriched (5 atom % NH4 15NO3) Hoagland Nutrient Solutions resulting in enriched rye [0.799% atom % 15N, 24:1 carbon (C):N ratio] and enriched clover (0.686% atom % 15N, 19:1 C:N ratio). Cover crops were applied as an equal mixture of rye and clover at 1884, 3768, and 5652 kg·ha− 1 dry weight to supply 26, 52, and 78 kg·ha− 1 N. Enriched materials were only applied at the 3768 kg·ha− 1 rate, either as enriched rye plus non-enriched clover or non-enriched rye plus enriched clover. Additional treatments consisted of an unfertilized control and three NH4NO3 fertilizer rates; 112, 224, and 336 kg·ha− 1 N for broccoli and 70, 140, and 210 kg·ha− 1 N for lettuce. Combination treatments were the standard cover crop rate (3768 kg·ha− 1) plus the lowest N fertilizer rate for each vegetable. Cover crops did not increase yield of either broccoli or lettuce, and contributed only 17% of the N in broccoli and 15% of the N in lettuce. The majority of cover crop 15N remained in the soil: 54.8% and 81.3% of rye and clover N, respectively, after broccoli harvest; and 68.1% and 79.2% of rye and clover N, respectively, after lettuce harvest. Broccoli plant tissue recoveries were 8.0% of the rye and 11.0 % of the clover 15N; while lettuce plant tissue recoveries were 6.3% (rye) and 4.1% (clover). Broccoli yield could not be assessed due to lack of floret development, but dry matter accumulation was maximized at 224 kg·ha− 1N. Lettuce yield and fertilizer N recovery efficiency (by mass balance) was maximized at 140 g·ha− 1 N. Keywords: 15N recovery Brassica oleracea var. italica broccolicovers cropscrimson cloverfertilizer N erecovery Latuca sativa lettuceryeN uptake Secale cereale, spring vegetables Trifolium incarnatum ACKNOWLEDGMENTS Financial support for this study was provided by the NCA & TSU Agricultural Research Program (Evans-Allen Funds). The authors acknowledge the assistance of Howard Sanford, NCSU for N15 analysis; Dr. W.A.R.N. Fernando for statistical analysis and manuscript review; Dr. V. Shirley, P. Nouri, H. Parks and Pam Britt for sample analysis the samples and maintenance of the crops in the greenhouse; and Pamela E. Puryear of the Tobacco Literature Service for reference identification. This paper is a portion of a thesis submitted by R.L. Holness. The use of trade names in this publication does not imply endorsement of the products named, or criticism of similar ones not mentioned. Notes zUnless otherwise indicated, the cover crops are an equal mixture by weight of non-enriched clover and rye. yThis treatment was an equal mixture by weight of non-enriched clover plus 15N enriched rye. xThis treatment was an equal mixture by weight of 15N enriched clover plus non-enriched rye. v The ANOVA for residual soil inorganic N in broccoli was not significant at P ≤ 0.05. DA - 2008/// PY - 2008/// DO - 10.1080/01904160802097359 VL - 31 IS - 6 SP - 1033-1045 SN - 1532-4087 KW - N-15 recovery KW - Brassica oleracea var. italica KW - broccoli KW - covers crops KW - crimson clover KW - fertilizer N erecovery KW - Latuca sativa KW - lettuce KW - rye KW - N uptake KW - Secale cereale KW - spring vegetables KW - Trifolium incarnatum ER - TY - JOUR TI - Cover crop effects on the activity-density of the weed seed predator Harpalus rufipes (Coleoptera : Carabidae) AU - Shearin, Amanda F. AU - Reberg-Horton, S. Chris AU - Gallandt, Eric R. T2 - WEED SCIENCE AB - Cover crop systems were investigated in 2004 and 2005 for their effects on the activity-density (a function of movement and density) of a promising group of weed biocontrol organisms, the ground beetles collectively known as carabids, with particular emphasis on a beneficial carabid species Harpalus rufipes DeGeer. Marked H. rufipes released into pea/oat–rye/vetch cover crop plots were more than twice as likely to be recaptured within the same plots as beetles released in nonvegetated fallow plots (18 and 8%, respectively). Marked beetles released into fallow plots were more than twice as likely to leave their plots and be recaptured in pea/oat–rye/vetch plots as vice versa (13 vs. 5%), indicating a clear preference for habitat with vegetative cover. Overall recapture rates were not different between treatments. Unmarked H. rufipes activity-density was also higher in pea/oat–rye/vetch compared to fallow plots. Additionally, five cover crop systems, including the fallow and pea/oat–rye/vetch treatments, and two residue management methods (conventional and zone tillage) were investigated from June to August in 2005 for their effects on H. rufipes activity-density. Corn was planted in 2005 into residues of the five cover crop systems grown in 2004. H. rufipes activity-density was higher in zone and conventionally tilled corn planted in pea/oat–rye/vetch residues and conventionally tilled corn planted in red clover/oat residues than in any other cover crop and residue management combination. Pea/oat–rye/vetch cover crop systems are apparently beneficial for H. rufipes during the cover crop year as well as in subsequent crops planted into this cover crop's residues. This system was not the least disturbed system but, based on the number of tillage events, represented a medium level of disturbance among the various systems. Thus, some level of disturbance might be beneficial for H. rufipes , but how and when that soil disturbance occurs requires further research to determine the best means of conserving this species. DA - 2008/// PY - 2008/// DO - 10.1614/WS-07-137.1 VL - 56 IS - 3 SP - 442-450 SN - 0043-1745 KW - weed seed predation KW - Harpalus rufipes KW - cover crops KW - carabids ER - TY - JOUR TI - Virulence structure of the Eastern US wheat powdery mildew population AU - Parks, Ryan AU - Carbone, Ignazio AU - Murphy, J. Paul AU - Marshall, David AU - Cowger, Christina T2 - PLANT DISEASE AB - Little is known about the population structure of wheat powdery mildew in the eastern United States, and the most recent report on virulence in this population involved isolates collected in 1993–94. In the present study, wheat leaves naturally infected with powdery mildew were collected from 10 locations in the southeastern United States in 2003 and 2005 and a collection of 207 isolates was derived from single ascospores. Frequencies of virulence to 16 mildew resistance (Pm) genes were determined by inoculating the isolates individually on replicated plates of detached leaves of differential wheat lines. These virulence frequencies were used to infer local effectiveness of Pm genes, estimate virulence complexity, detect significant associations between pairs of pathogen avirulence loci, and assess whether phenotypic differences between pathogen subpopulations increased with geographic distance. In both years, virulence to Pm3a, Pm3c, Pm5a, and Pm7 was present in more than 90% of sampled isolates and virulence to Pm1a, Pm16, Pm17, and Pm25 was present in fewer than 10% of isolates. In each year, 71 to 88% of all sampled isolates possessed one of a few multilocus virulence phenotypes, although there were significant differences among locations in frequencies of virulence to individual Pm genes. Several significant associations were detected between alleles for avirulence to pairs of Pm genes. Genetic (phenotypic) distance between isolate subpopulations increased significantly (R 2 = 0.40, P < 0.001) with increasing geographic separation; possible explanations include different commercial deployment of Pm genes and restricted gene flow in the pathogen population. DA - 2008/7// PY - 2008/7// DO - 10.1094/PDIS-92-7-1074 VL - 92 IS - 7 SP - 1074-1082 SN - 0191-2917 KW - Blumeria graminis f. sp tritici KW - Triticum aestivum ER - TY - JOUR TI - Sorption of ferric iron from ferrioxamine B to synthetic and biogenic layer type manganese oxides AU - Duckworth, Owen W. AU - Bargar, John R. AU - Sposito, Garrison T2 - GEOCHIMICA ET COSMOCHIMICA ACTA AB - Siderophores are biogenic chelating agents produced in terrestrial and marine environments that increase the bioavailability of ferric iron. Recent work has suggested that both aqueous and solid-phase Mn(III) may affect siderophore-mediated iron transport, but scant information appears to be available about the potential roles of layer type manganese oxides, which are relatively abundant in soils and the oligotrophic marine water column. To probe the effects of layer type manganese oxides on the stability of aqueous Fe–siderophore complexes, we studied the sorption of ferrioxamine B [Fe(III)HDFOB+, an Fe(III) chelate of the trihydroxamate siderophore desferrioxamine B (DFOB)] to two synthetic birnessites [layer type Mn(III,IV) oxides] and a biogenic birnessite produced by Pseudomonas putida GB-1. We found that all of these predominantly Mn(IV) oxides greatly reduced the aqueous concentration of Fe(III)HDFOB+ at pH 8. Analysis of Fe K-edge EXAFS spectra indicated that a dominant fraction of Fe(III) associated with the Mn(IV) oxides is not complexed by DFOB as in solution, but instead Fe(III) is specifically adsorbed to the mineral structure at multiple sites, thus indicating that the Mn(IV) oxides displaced Fe(III) from the siderophore complex. These results indicate that layer type manganese oxides, including biogenic minerals, may sequester iron from soluble ferric complexes. We conclude that the sorption of iron–siderophore complexes may play a significant role in the bioavailability and biogeochemical cycling of iron in marine and terrestrial environments. DA - 2008/7/15/ PY - 2008/7/15/ DO - 10.1016/j.gca.2008.04.026 VL - 72 IS - 14 SP - 3371-3380 SN - 1872-9533 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-45849086926&partnerID=MN8TOARS ER - TY - JOUR TI - Solute transport in the capillary fringe and shallow groundwater: Field evaluation AU - Abit, S. M. AU - Amoozegar, Aziz AU - Vepraskas, Michael AU - Niewoehner, C. P. T2 - Vadose Zone Journal DA - 2008/// PY - 2008/// DO - 10.2136/vzj.2007.0102 VL - 7 IS - 3 SP - 890–898 ER - TY - JOUR TI - Relationships between oleic and linoleic acid content and seed colonization by Cercospora kikuchii and Diaporthe phaseolorum AU - Xue, H. Q. AU - Upchurch, R. G. AU - Kwanyuen, P. T2 - PLANT DISEASE AB - Compared with standard cultivars, seed of mid-oleic soybean genotypes sometimes have shown increased colonization by Cercospora kikuchii in the field as judged by increased levels of purple-stained seed. To examine relationships between oleic and linoleic acid levels in soybean seed and postharvest seed colonization by two fungal seed pathogens, we inoculated seed with differing oleic:linoleic acid (O/L) ratios. Seed with defined O/L ratios were produced by allowing seed development of two isogenic soybean lines to occur in three different air temperature environments. Seed produced in these environments were harvested, individually analyzed for fatty acid composition, and inoculated with mycelium preparations of the fungal seed pathogens C. kikuchii or Diaporthe phaseolorum var. sojae. Fungal biomass of infected seed was quantified by measuring in vitro ergosterol content. For both soybean lines, colonization by C. kikuchii was positively correlated with the O/L ratio (r = 0.55, P < 0.03) and oleic acid content (r = 0.61, P < 0.02), and negatively correlated with linoleic (r = –0.60, P < 0.02) and linolenic (r = –0.58, P < 0.03) acid content. No association was found between the extent of seed colonization by D. phaseolorum and the seed O/L ratio. Our data suggest that the O/L ratio may be related to soybean seed colonization by C. kikuchii, but there is no evidence of a relationship with D. phaseolorum var. sojae colonization. DA - 2008/7// PY - 2008/7// DO - 10.1094/PDIS-92-7-1038 VL - 92 IS - 7 SP - 1038-1042 SN - 1943-7692 ER - TY - JOUR TI - RNA interference (RNAi)-induced suppression of nicotine demethylase activity reduces levels of a key carcinogen in cured tobacco leaves AU - Lewis, Ramsey S. AU - Jack, Anne M. AU - Morris, Jerry W. AU - Robert, Vincent J. M. AU - Gavilano, Lily B. AU - Siminszky, Balazs AU - Bush, Lowell P. AU - Hayes, Alec J. AU - Dewey, Ralph E. T2 - PLANT BIOTECHNOLOGY JOURNAL AB - Summary Technologies for reducing the levels of tobacco product constituents that may contribute to unwanted health effects are desired. Target compounds include tobacco‐specific nitrosamines (TSNAs), a class of compounds generated through the nitrosation of pyridine alkaloids during the curing and processing of tobacco. Studies have reported the TSNA N ′‐nitrosonornicotine (NNN) to be carcinogenic in laboratory animals. NNN is formed via the nitrosation of nornicotine, a secondary alkaloid produced through enzymatic N ‐demethylation of nicotine. Strategies to lower nornicotine levels in tobacco ( Nicotiana tabacum L.) could lead to a corresponding decrease in NNN accumulation in cured leaves. The major nicotine demethylase gene of tobacco has recently been isolated. In this study, a large‐scale field trial was conducted to evaluate transgenic lines of burley tobacco carrying an RNA interference (RNAi) construct designed to inhibit the expression of this gene. Selected transgenic lines exhibited a six‐fold decrease in nornicotine content relative to untransformed controls. Analysis of cured leaves revealed a commensurate decrease in NNN and total TSNAs. The inhibition of nicotine demethylase activity is an effective means of decreasing significantly the level of a key defined animal carcinogen present in tobacco products. DA - 2008/5// PY - 2008/5// DO - 10.1111/j.1467-7652.2008.00324.x VL - 6 IS - 4 SP - 346-354 SN - 1467-7644 KW - nicotine demethylase KW - N'-nitrosonornicotine KW - RNA interference KW - tobacco carcinogens KW - tobacco-specific nitrosamines (TSNAs) ER - TY - JOUR TI - Phosphorus requirements of St. Augustinegrass grown in sandy soils AU - Liu, Min AU - Sartain, J. B. AU - Trenholm, L. E. AU - Miller, G. L. T2 - CROP SCIENCE AB - Phosphorus fertilization of St. Augustinegrass [ Stenotaphrum secondatum (Walt.) Kuntze] is performed on the basis of soil tests designed for agronomic crops. The objectives of this study were to determine the critical minimum P application rate and soil and tissue P concentration of St. Augustinegrass grown in sandy soils. Three studies were conducted in a glasshouse using a Pomona sand, two Tavares sands, and a Pottsburg sand. Established pots of ‘Floratam’ St. Augustinegrass received P at 0, 0.14, 0.27, 0.54, and 1.09 g m −2 every four weeks for 16 weeks for Study 1 and 12 weeks for Studies 2 and 3. Critical minimum tissue P concentration was determined to be 1.8 g kg −1 on dry weight basis. Minimum P application rate was 0.14 g m −2 4‐wk −1 to obtain acceptable turfgrass quality and growth rate. Additional growth was not observed when Mehlich‐1 P level was greater than 7, 8, 9, and 5 mg kg −1 for Pomona sand, Tavares sand (a), Pottsburg sand, and Tavares sand (b), respectively. Phosphorus fertilization would not be recommended if soil Mehlich‐1 P concentration is above 10 mg kg −1 for sandy soils or tissue P level is beyond 1.8 g kg −1 on dry weight basis. Phosphorus application of 0.14 g m −2 4‐wk −1 is recommended when P is required. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.09.0506 VL - 48 IS - 3 SP - 1178-1186 SN - 1435-0653 ER - TY - JOUR TI - Interpreting morphological features in wetland soils with a hydrologic model AU - Vepraskas, M. J. AU - Caldwell, P. V. T2 - CATENA AB - Wetlands in the United States are protected by law and are identified by their hydric soils, wetland hydrology, and vegetation. Hydric soils are easily identified by color characteristics termed hydric soil field indicators, that form under saturated and anaerobic conditions, but wetland hydrology is difficult to assess. This study determines how often seven hydric soil field indicators met wetland hydrology requirements which require a water table be within 30 cm of the surface for 14 days or more during the growing season in over half the years. Studies were conducted at five sites in North Carolina in both wetland and upland plots. Soils ranged from Aquic Paleudults to Typic Haplosaprists across all sites. The water-table simulation model DRAINMOD was calibrated to soil conditions in individual plots. Long-term rainfall data were used with the calibrated models to compute 40 years of daily water table data to represent both wet and dry years. It was found that the hydric soils with field indicators composed of organic materials in layers over 20 cm thick (Histosol and Histic epipedon field indicators) met wetland hydrology requirements each year, and in addition were ponded with water for periods between 67 to 139 days on average each year during the growing season. Plots in mineral soils having the Dark Surface (S7) indicator as well as the Sandy Mucky Mineral (S1) indicator also met the saturation requirements for wetland hydrology every year, and were ponded for only 3 days per year on average. Other mineral soils with an Umbric Surface (F13) or a Depleted Matrix (F3) field indicator met wetland hydrology requirements in approximately 95% of the years, and had water tables within 30 cm of the surface for 40 days per year on average. The Redox Depressions (F8) field indicator occurred in a small depression that was saturated for 87% of the year for periods averaging approximately 30 days. These results showed that hydric soil field indicators can be calibrated to long-term water table data that will allow precise assessments of wetland hydrology on-site. DA - 2008/4/15/ PY - 2008/4/15/ DO - 10.1016/j.catena.2007.07.005 VL - 73 IS - 2 SP - 153-165 SN - 1872-6887 KW - wetlands KW - hydric soils KW - wetland hydrology KW - modeling ER - TY - JOUR TI - Hydropedology: Fundamental issues and practical applications AU - Lin, Henry AU - Bouma, Johan AU - Owens, Phillip AU - Vepraskas, Michael T2 - CATENA DA - 2008/4/15/ PY - 2008/4/15/ DO - 10.1016/j.catena.2007.09.004 VL - 73 IS - 2 SP - 151-152 SN - 1872-6887 ER - TY - JOUR TI - Hydropedology of a coarse-loamy catena in the lower Coastal Plain, NC AU - Severson, E. D. AU - Lindbo, D. L. AU - Vepraskas, M. J. T2 - CATENA AB - The identification of the depth of seasonal saturation in soils is critical for a multitude of land uses including the siting and design of septic systems and delineation of wetlands. Often 2 chroma redox depletions are used to make this determination; however, other redoximorphic features are also related to saturation. With increasing land use intensities and environmental concerns it is important to understand exactly how redoximorphic features (RMFs) relate to saturation. The objective of this research is to relate RMFs to saturation in a coarse-loamy catena in the lower coastal plain in North Carolina. A relatively undisturbed site in eastern NC was identified and three transects were instrumented with recording wells, redox probes and thermocouples. A rain gauge was also located at the site. In all the soils investigated, ≤ 2 chroma redox depletions related to an average cumulative annual saturation percentage (CSP) of 15%. However, the ≤ 2 chroma redox depletions indicated a larger CSP in the MWD soils (19%) as compared to the SWPD soils (11%). This suggests that ≤ 2 chroma redox depletions do not mean the same thing in all soils. Regulations that rely on this single feature may be identifying different degrees of saturation and thus may have a varying implication to wastewater treatment and water quality. DA - 2008/4/15/ PY - 2008/4/15/ DO - 10.1016/j.catena.2007.09.001 VL - 73 IS - 2 SP - 189-196 SN - 0341-8162 KW - redoximorphic features KW - water tables KW - hydrology KW - redox KW - saturation ER - TY - JOUR TI - Evaluation phosphorus loss from a Florida Spodosal as affected by phosphorus-source application methods AU - Agyin-Birikorang, S. AU - O'Connor, G. A. AU - Brinton, S. R. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Incorporating applied phosphorus (P) sources can reduce P runoff losses and is a recommended best management practice. However, in soils with low P retention capacities, leaching can be a major mechanism for off-site P loss, and the P-source application method (surface or incorporation) may not significantly affect the total amount of off-site P loss. We utilized simulated rainfall protocols to investigate effects of P-source characteristics and application methods on the forms and amounts of P losses from six P sources, including five biosolids materials produced and/or marketed in Florida, and one inorganic fertilizer (triple superphosphate). A typical Florida Spodosol (Immokalee fine sand; sandy, siliceous, hyperthermic Arenic Alaquods) was used for the study, to which the P sources were each applied at a rate of 224 kg P ha(-1) (approximately the P rate associated with N-based biosolids applications). The P sources were either surface-applied to the soil or incorporated into the soil to a depth of 5 cm. Amended soils were subjected to three simulated rainfall events, at 1-d intervals. Runoff and leachate were collected after each rainfall event and analyzed for P losses in the form of soluble reactive P (SRP), total dissolved P (TDP), total P (TP), and bioavailable P (BAP) (in runoff only). Cumulative masses (runoff + leachate for the three rainfall events) of P losses from all the P sources were similar, whether the amendments were surface-applied or incorporated into the soil. The solubility of the amendment, rather than application method, largely determines the P loss potential in poorly P-sorbing Florida Spodosols. DA - 2008/// PY - 2008/// DO - 10.2134/jeq2007.0535 VL - 37 IS - 3 SP - 1180-1189 SN - 1537-2537 ER - TY - JOUR TI - Effect of planting date and nitrogen fertilization rates on no-till pumpkins AU - Harrelson, E. R. AU - Hoyt, G. D. AU - Havlin, J. L. AU - Monks, D. W. T2 - HortScience DA - 2008/// PY - 2008/// VL - 43 IS - 3 SP - 857-861 ER - TY - JOUR TI - Effect of a hydrophobic layer on the upward movement of water under surface-freezing conditions AU - Gieselman, Heath AU - Heitman, Joshua L. AU - Horton, Roert T2 - SOIL SCIENCE AB - A water table can increase the severity of frost heave in soil by providing water for accumulation at the freezing front. Limiting flow from the water table can reduce frost heave. We hypothesized that a hydrophobic soil layer positioned between the freezing front and the water table would restrict water flow and ice accumulation at the freezing front. This hypothesis was tested in laboratory experiments using 20-cm-long soil cells designed to achieve one-dimensional flow conditions between an imposed −5 °C upper boundary and a water table at the lower cell boundary. Experiments were performed with 24 and 10 °C lower boundary temperatures. Dichlorodimethylsilane-treated soil was used to provide a 2-cm thick hydrophobic soil layer above the water table; cells with and without hydrophobic layers were used for comparison. For both lower boundary temperatures, the freezing front advanced more rapidly in the soil cells with hydrophobic layers. Final water uptake volumes corresponded to only 5% of the initial cell pore volume for cells with hydrophobic layers, but more than 20% for cells without hydrophobic layers. Although only slightly larger amounts of frost heave were observed in cells without hydrophobic layers, water contents at the freezing front indicated much greater expansion and deformation within the cells when the hydrophobic layer was absent. Overall, the hydrophobic layer reduced water uptake and ice accumulation at the freezing front. DA - 2008/5// PY - 2008/5// DO - 10.1097/SS.0b013e31816d1e75 VL - 173 IS - 5 SP - 297-305 SN - 1538-9243 KW - frozen soil KW - hydrophobic soil KW - ice formation KW - soil water flow KW - soil heat transfer ER - TY - JOUR TI - Long-term agricultural research: A research, education, and extension imperative AU - Robertson, G. Philip AU - Allen, Vivien G. AU - Boody, George AU - Boose, Emery R. AU - Creamer, Nancy G. AU - Drinkwater, Laurie E. AU - Gosz, James R. AU - Lynch, Lori AU - Havlin, John L. AU - Jackson, Louise E. AU - Pickett, Steward T. A. AU - Pitelka, Louis AU - Randall, Alan AU - Reed, A. Scott AU - Seastedt, Timothy R. AU - Waide, Robert B. AU - Wall, Diana H. T2 - BIOSCIENCE AB - For agriculture to meet goals that include profitability, environmental integrity, and the production of ecosystem services beyond food, fuel, and fiber requires a comprehensive, systems-level research approach that is long-term and geographically scalable. This approach is largely lacking from the US agricultural research portfolio. It is time to add it. A long-term agricultural research program would substantially improve the delivery of agricultural products and other ecosystem services to a society that calls for agriculture to be safe, environmentally sound, and socially responsible. DA - 2008/// PY - 2008/// DO - 10.1641/B580711 VL - 58 IS - 7 SP - 640-645 SN - 0006-3568 KW - agriculture KW - long-term research KW - sustainability KW - LTER KW - agricultural extension and education ER - TY - JOUR TI - Increased protein carbonylation in leaves of Arabidopsis and soybean in response to elevated [CO2] AU - Qiu, Quan-Sheng AU - Huber, Joan L. AU - Booker, Fitzgerald L. AU - Jain, Vanita AU - Leakey, Andrew D. B. AU - Fiscus, Edwin L. AU - Yau, Peter M. AU - Ort, Donald R. AU - Huber, Steven C. T2 - PHOTOSYNTHESIS RESEARCH AB - While exposure of C3 plants to elevated [CO2] would be expected to reduce production of reactive oxygen species (ROS) in leaves because of reduced photorespiratory metabolism, results obtained in the present study suggest that exposure of plants to elevated [CO2] can result in increased oxidative stress. First, in Arabidopsis and soybean, leaf protein carbonylation, a marker of oxidative stress, was often increased when plants were exposed to elevated [CO2]. In soybean, increased carbonyl content was often associated with loss of leaf chlorophyll and reduced enhancement of leaf photosynthetic rate (Pn) by elevated [CO2]. Second, two-dimensional (2-DE) difference gel electrophoresis (DIGE) analysis of proteins extracted from leaves of soybean plants grown at elevated [CO2] or [O3] revealed that both treatments altered the abundance of a similar subset of proteins, consistent with the idea that both conditions may involve an oxidative stress. The 2-DE analysis of leaf proteins was facilitated by a novel and simple procedure to remove ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from soluble soybean leaf extracts. Collectively, these findings add a new dimension to our understanding of global change biology and raise the possibility that oxidative signals can be an unexpected component of plant response to elevated [CO2]. DA - 2008/8// PY - 2008/8// DO - 10.1007/s11120-008-9310-5 VL - 97 IS - 2 SP - 155-166 SN - 1573-5079 KW - Arabidopsis KW - ascorbate peroxidase KW - 2-dimensional gel electrophoresis KW - protein carbonylation KW - soybean ER - TY - JOUR TI - Climatic adaptation and ecological descriptors of 42 Mexican maize races AU - Ruiz Corral, Jose Ariel AU - Puga, Noe Duran AU - Sanchez Gonzalez, Jose de Jesus AU - Parra, Jose Ron AU - Gonzalez Eguiarte, Diego Raymundo AU - Holland, J. B. AU - Medina Garcia, Guillermo T2 - CROP SCIENCE AB - To better understand the range of adaptation of maize ( Zea mays L.) landraces, climatic adaptation intervals of 42 Mexican maize races were determined. A database of 4161 maize accessions was used to characterize altitudinal and climatic conditions where the 42 maize races grow, yielding ecological descriptors for each race. Using the geographical coordinates of the collection sites of each accession, their climatic conditions were characterized using the geographic information system IDRISI and a national environmental information system. Analyses of variance and cluster analyses of the racial ecological descriptors were performed to determine possible environmental groupings of the races. We found a very high level of variation among and within Mexican maize races for climate adaptation and ecological descriptors. The general overall climatic ranges for maize were 0 to 2900 m of altitude, 11.3 to 26.6°C annual mean temperature, 12.0 to 29.1°C growing season mean temperature, 426 to 4245 mm annual rainfall, 400 to 3555 mm growing season rainfall, and 12.46 to 12.98 h mean growing season daylength. These climatic ranges of maize surpass those from its closest relative, teosinte ( Z. mays ssp. parviglumis Iltis and Doebley), indicating that maize has evolved adaptability beyond the environmental range in which ancestral maize was first domesticated. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.09.0518 VL - 48 IS - 4 SP - 1502-1512 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-49149121288&partnerID=MN8TOARS ER - TY - JOUR TI - Weed management and crop response with glyphosate, s-metolachlor, trifloxysulfuron, prometryn, and MSMA in glyphosate-resistant cotton AU - Clewis, Scott B. AU - Miller, D. K. AU - Koger, C. H. AU - Baughman, T. A. AU - Price, A. J. AU - Porterfield, D. AU - Wilcut, J. W. T2 - WEED TECHNOLOGY AB - Field studies were conducted in five states at six locations from 2002 through 2003 to evaluate weed control and cotton response to early POST (EPOST), POST/POST-directed spray (PDS), and late POST-directed (LAYBY) systems using glyphosate-trimethylsulfonium salt (TM), s-metolachlor, trifloxysulfuron, prometryn, and MSMA. Early POST applications were made from mid May through mid June; POST/PDS applications were made from early June through mid July; and LAYBY applications were made from early July through mid August. Early season cotton injury and discoloration was minimal (< 1%) with all treatments; mid- and late-season injury was minimal (< 2%) except for trifloxysulfuron POST (11 and 9%, respectively). Annual grasses evaluated included barnyardgrass, broadleaf signalgrass, goosegrass, and large crabgrass. Broadleaf weeds evaluated included entireleaf morningglory, pitted morningglory, sicklepod, and smooth pigweed. For the EPOST, POST/PDS, and LAYBY applications, weeds were at cotyledon to 10 leaf, 1 to 25 leaf, and 2 to 25 leaf stage, respectively. Annual broadleaf and grass control was increased with the addition of s-metolachlor to glyphosate-TM EPOST systems (85 to 98% control) compared with glyphosate-TM EPOST alone (65 to 91% control), except for sicklepod control where equivalent control was observed. Annual grass control was greater with glyphosate-TM plus trifloxysulfuron PDS than with trifloxysulfuron POST or PDS, or trifloxysulfuron plus MSMA PDS (90 to 94% vs. 75 to 83% control). With few exceptions, broadleaf weed control was equivalent for trifloxysulfuron applied POST alone or PDS alone or in combination with glyphosate-TM PDS or MSMA PDS herbicide treatments (81 to 99% control). The addition of a LAYBY herbicide treatment increased broadleaf weed control by 11 to 36 percentage points compared with systems without a LAYBY. Cotton lint yield increased 420 kg/ha with the addition of s-metolachlor to glyphosate-TM EPOST treatments compared with systems without s-metolachlor EPOST. Cotton lint yield was increased 330 to 910 kg/ha with the addition of a POST herbicide treatment compared with systems without a POST/PDS treatment. The addition of a LAYBY herbicide treatment increased cotton lint yield by 440 kg/ha compared with systems without a LAYBY.Nomenclature: Glyphosate-TM, MSMA, prometryn, s-metolachlor, trifloxysulfuron, barnyardgrass, Echinochloa crus-galli (L.) Beauv. ECHCG, broadleaf signalgrass, Brachiaria platyphylla (Griseb.) Nash. BRAPP, entireleaf morningglory, Ipomoea hederacea var. integriuscula Gray. IPOHG, goosegrass, Eleusine indica (L.) Gaertn. ELEIN, arge crabgrass, Digitaria sanguinalis (L.) Scop. DIGSA, pitted morningglory, Ipomoea lacunosa L. IPOLA, sicklepod, Cassia obtusifolia L. CASOB, smooth pigweed, Amaranthus hybridus L. AMACH, cotton, Gossypium hirsutum L. ‘DP 458 RR/BG’, ‘DP 555 RR/BG’, ‘FM 989 RR/BG’, ‘PM 2344 RR/BG’, ‘ST 4793 RR’ DA - 2008/// PY - 2008/// DO - 10.1614/wt-07-082.1 VL - 22 IS - 1 SP - 160-167 SN - 0890-037X KW - trimethylsulfonium salt KW - weed management ER - TY - JOUR TI - Sustaining public plant breeding to meet future national needs AU - Hancock, J. F. AU - Stuber, C. T2 - HortScience DA - 2008/// PY - 2008/// VL - 43 IS - 2 SP - 298-299 ER - TY - JOUR TI - Soil property indices for assessing short-term changes in soil quality AU - Bell, M. C. AU - Raczkowski, C. W. T2 - RENEWABLE AGRICULTURE AND FOOD SYSTEMS AB - Abstract Soil quality has been proposed as a prime indicator for characterizing and defining management factors contributing to soil degradation. In this study, biological (soil respiration, fluorescent Pseudomonas bacteria and entomopathogenic nematode populations), chemical (pH, inorganic N, and total C & N), and physical (bulk density and infiltration) indicators were used to determine soil quality. The specific research objective was to determine the capacity of this specific set of indicators to assess soil quality and determine its ability to detect short-term changes in soil conditions and processes. The assessment was comparative because of the lack of specific criteria or guidelines available in the literature for interpretation of most soil property indices measured. The following treatments were chosen from an ongoing farming systems study to achieve a preplanned set of comparisons that would make this type of assessment possible: (1) best management practices/conventional tillage (BMP/CT), (2) BMP/no-tillage (BMP/NT), (3) an organic system, and (4) a successional fallow system. Assessments were made multiple times between 1999 and 2000. Statistical differences between systems were found for all soil quality indicators except for entomopathogenic nematodes. Differences between systems varied across dates, a result that supports other research stating the need to consider the temporal variability of these indices for an unbiased overall soil quality assessment. Differences in total carbon and total nitrogen between systems were most evident in the 2000 sampling dates with BMP/NT showing greater contents on the last sampling date. The soil pH and inorganic N results did not suggest a possible difference in soil function status between any of the three agricultural systems studied. All three agricultural systems, BMP/NT, BMP/CT and organic, had similar pH values and overall low soil inorganic N levels. The non-agricultural successional system had a slightly more acidic soil condition than the three agricultural systems. Soil bulk density increased with time in the untilled BMP/NT and successional systems but the resulting values were not considered detrimental to either productivity or environmental quality. Infiltration was lower in the BMP/NT and successional systems than in the BMP/CT and organic systems. In conclusion, all soil quality indicators except for entomopathogenic nematodes proved to be sensitive to the detection of rapid changes in soil conditions that occur by the influence of soil management. The importance of using soil bulk density to express soil results on a volume basis, as the soil exists in the field before sampling, prevented an average interpretation error of 7–14% as compared to treatment comparisons on a soil weight basis only. This also demonstrates the need to carefully consider field sampling locations (row, between row, or wheel traffic areas) which dramatically influence soil density, physical characteristics, organic matter concentrations, and biological activity. Failure to consider these factors can invalidate even the most careful approaches to establishing baseline soil quality levels in the field as affected by various tillage and residue management practices and associated comparisons in time. DA - 2008/3// PY - 2008/3// DO - 10.1017/s1742170507001883 VL - 23 IS - 1 SP - 70-79 SN - 1742-1713 KW - large-scale systems research KW - multidisciplinary research KW - soil function KW - best management practices KW - no tillage KW - conventional tillage KW - organic ER - TY - JOUR TI - Sensor-based automation of irrigation on bermudagrass, during wet weather conditions AU - Cardenas-Lailhacar, B. AU - Dukes, M. D. AU - Miller, Grady T2 - Journal of Irrigation and Drainage Engineering AB - New technologies could improve irrigation efficiency of turfgrass, promoting water conservation and reducing environmental impacts. The objectives of this research were to quantify irrigation water use and to evaluate turf quality differences between (1) time-based scheduling with and without a rain sensor (RS); (2) a time-based schedule compared to a soil moisture sensor (SMS)-based irrigation system; and (3) different commercially available SMS systems. The experimental area consisted of common bermudagrass [Cynodon dactylon (L.) Pers.] plots (3.7m×3.7m), located in Gainesville, Fla. The monitoring period took place from July 20 to December 14, 2004, and from March 25 to August 31, 2005. SMS-based treatments consisted of irrigating one, two, or seven days a week, each with four different commercial SMS brands. Time-based treatments with or without RS and a nonirrigated treatment were also implemented. Significant differences in turfgrass quality among treatments were not detected due to the sustained wet weather conditions during the testing periods. The treatment with the rain sensor resulted in 34% less water applied than that without the rain sensor (2-WORS) treatment. Most SMS brands recorded irrigation water savings compared to 2-WORS, ranging from 69 to 92% for three of four SMSs tested, depending on the irrigation frequency. Therefore, SMS systems represent a promising technology because of the water savings that they can achieve during wet weather conditions while maintaining acceptable turfgrass quality. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)0733-9437(2008)134:2(120) VL - 134 IS - 2 SP - 120–128 ER - TY - JOUR TI - Seeded watermelon and weed response to halosulfuron applied preemergence and postemergence AU - Macrae, Andrew W. AU - Culpepper, A. Stanley AU - Batts, Roger B. AU - Lewis, Kenneth L. T2 - WEED TECHNOLOGY AB - Managing weeds in watermelon is challenging because of the limited availability of herbicides approved for use in this crop. Field experiments on efficacy and crop tolerance were conducted to determine the potential for halosulfuron use in watermelon in Georgia and North Carolina. Halosulfuron was applied PRE, early POST (EPOST; one-leaf watermelon), and late POST (LPOST; watermelon with 30-cm runners) at 26, 39, and 52 g ai/ha. Under weed-free conditions, PRE treatments did not injure watermelon. EPOST and LPOST treatments caused 45 and 34% injury 2 wk after treatment, respectively, averaged over halosulfuron rate. EPOST treatments reduced watermelon fruit number and total weight by 15 and 22%, respectively, and LPOST treatments reduced total fruit weight 12%. Halosulfuron PRE at 39 or 52 g/ha provided 94% or greater control of carpetweed, Palmer amaranth, and smooth pigweed. EPOST treatments controlled 84 and 88% of yellow nutsedge and smooth pigweed, respectively, but LPOST treatments controlled less than 83% of all weed species. Sequential applications of halosulfuron at 26 g/ha PRE and 26 g/ha LPOST controlled 89 to 99% of carpetweed, coffee senna, Palmer amaranth, smooth pigweed, and yellow nutsedge. Our data suggest growers can effectively use halosulfuron PRE in seeded watermelon. However, POST applications should be made only after watermelon has 30-cm runners and as a salvage spot treatment where previous weed control strategies have failed to provide adequate control.Nomenclature: Halosulfuron, carpetweed, Mollugo verticillata L. MOLVE, coffee senna, Cassia occidentalis (L.) Link CASOC, Palmer amaranth, Amaranthus palmeri S. Wats. AMAPA, smooth pigweed, Amaranthus hybridus L. AMACH, yellow nutsedge, Cyperus esculentus L. CYPES, watermelon, Citrullus lanatus (Thunb.) Matsum. & Nakai ‘Legacy’, ‘Sangria’, ‘Stargazer’ DA - 2008/// PY - 2008/// DO - 10.1614/wt-06-180.1 VL - 22 IS - 1 SP - 86-90 SN - 1550-2740 KW - growth stage KW - injury KW - tolerance KW - weed control KW - yield ER - TY - JOUR TI - Interaction of calcium and phytate in broiler diets. 2. Effects on total and soluble phosphorus excretion AU - Leytem, A. B. AU - Plumstead, P. W. AU - Maguire, R. O. AU - Kwanyuen, P. AU - Burton, J. W. AU - Brake, J. T2 - POULTRY SCIENCE AB - Dietary Ca has been reported to influence the amount of phytate excreted from broilers and affect the solubility of P in excreta. To address the effects of dietary Ca and phytate on P excretion, 12 dietary treatments were fed to broilers from 16 to 21 d of age. Treatments consisted of 3 levels of phytate P (0.10, 0.24, and 0.28%) and 4 levels of Ca (0.47, 0.70, 0.93, and 1.16%) in a randomized complete block design. Feed phytate concentrations were varied by formulating diets with 3 different soybean meals (SBM): a low-phytate SBM, a commercial SBM, and a high phytate Prolina SBM having phytate P concentrations of 0.15 to 0.51%. Fresh excreta was collected from cages during 2 separate 24-h periods; collection I commenced after the start of dietary treatments (16 to 17 d) and collection II followed a 3-d adaptation period (19 to 20 d). Ileal samples were also collected at 21 d. Excreta samples were analyzed for total P, water soluble P (WSP), and phytate P, whereas ileal samples were analyzed for total P and phytate P. Results indicated that excreta total P could be reduced by up to 63% and WSP by up to 66% with dietary inclusion of low-phytate SBM. There was a significant effect of dietary Ca on both the excreta WSP and the ratio of WSP:total P. As dietary Ca increased, the excreta WSP and WSP:total P decreased, with the effects being more pronounced following a dietary adaptation period. There was a linear relationship between the slope of the response in WSP to dietary Ca and feed phytate content for excreta from collection II (r(2) = 0.99). There was also a negative correlation between excreta phytate concentration and excreta WSP during both excreta collections. The response in WSP to dietary manipulation was important from an environmental perspective because WSP in excreta has been related to potential for off-site P losses following land application. DA - 2008/3// PY - 2008/3// DO - 10.3382/ps.2007-00229 VL - 87 IS - 3 SP - 459-467 SN - 0032-5791 KW - broiler KW - soluble phosphorus KW - excreta KW - phytate KW - environment ER - TY - JOUR TI - Interaction of calcium and phytate in broiler diets. 1. Effects on apparent prececal digestibility and retention of phosphorus AU - Plumstead, P. W. AU - Leytem, A. B. AU - Maguire, R. O. AU - Spears, J. W. AU - Kwanyuen, P. AU - Brake, J. T2 - POULTRY SCIENCE AB - Phytate P utilization from soybean meal (SBM) included in broiler diets has been shown to be poor and highly dependent on dietary Ca intake. However, the effect of Ca on P utilization and on the optimal ratio of Ca to nonphytate P (Ca:NPP) when diets contained varying levels of phytate has not been clearly shown and was the objective of this research. A factorial treatment structure was used with 4 dietary Ca levels from 0.47 to 1.16% and 3 levels of phytate P (0.28, 0.24, and 0.10%). Varying dietary phytate P levels were obtained by utilizing SBM produced from 3 varieties of soybeans with different phytate P concentrations. Ross 508 broiler chicks were fed 1 of 12 diets from 16 to 21 d of age. Excreta were collected from 16 to 17 d and from 19 to 20 d of age and ileal digesta was collected at 21 d of age. Apparent prececal P digestibility decreased when dietary Ca concentration increased and was higher when diets contained low-phytate SBM. The apparent digestibility of Ca and percentage of phytate P hydrolysis at the distal ileum were not reduced when dietary phytate P concentration increased. Including low-phytate SBM in diets reduced total P output in the excreta by 49% compared with conventional SBM. The optimum ratio of Ca:NPP that resulted in the highest P retention and lowest P excretion was 2.53:1, 2.40:1, and 2.34:1 for diets with 0.28, 0.24, and 0.10% phytate P. These data suggested that increased dietary Ca reduced the extent of phytate P hydrolysis and P digestibility and that the optimum Ca:NPP ratio at which P retention was maximized was reduced when diets contained less phytate P. DA - 2008/3// PY - 2008/3// DO - 10.3382/ps.2007-00231 VL - 87 IS - 3 SP - 449-458 SN - 1525-3171 KW - broiler KW - phosphorus KW - soybean meal KW - phytate KW - environment ER - TY - JOUR TI - Evaluation of application timing and efficacy of the fungicides fluazinam. and boscalid for control of Sclerotinia blight of peanut AU - Smith, D. L. AU - Garrison, M. C. AU - Hollowell, J. E. AU - Isleib, T. G. AU - Shew, B. B. T2 - CROP PROTECTION AB - Sclerotinia blight of peanut (Arachis hypogaea) is caused by the soilborne fungus Sclerotinia minor. Management of Sclerotinia blight of peanut requires an integrated approach that includes rotation with non-hosts, resistant cultivars, cultural practices, and fungicides. Greenhouse experiments compared fluazinam and boscalid and investigated pre- and post-inoculation applications of fungicide or no fungicide to control infections by S. minor. Significant reductions in successful infections in the greenhouse occurred when fungicide was applied prior to, or up to 2 d after, inoculation, but not when applied 4 d after inoculation. Field experiments were conducted from 2004 to 2006 to investigate the comparative efficacy of the fungicides fluazinam and boscalid using alternating sequences of those fungicides or no fungicide for each of three sprays per season. In the field, applications of fungicide that preceded the largest incremental increase in disease incidence provided the best control of disease or increased yield. In both the field and greenhouse studies boscalid performed marginally better than fluazinam. Disease advisories or intensive scouting should be used to determine when epidemics initiate so that a fungicide can be applied prior to infection. DA - 2008/// PY - 2008/// DO - 10.1016/j.cropro.2007.11.010 VL - 27 IS - 3-5 SP - 823-833 SN - 0261-2194 KW - Sclerotinia minor KW - Sclerotinia blight KW - peanut KW - fungicide groundnut KW - logistic regression ER - TY - JOUR TI - Critical period of weed interference in peanut AU - Everman, Wesley J. AU - Clewis, Scott B. AU - Thomas, Walter E. AU - Burke, Ian C. AU - Wilcut, John W. T2 - WEED TECHNOLOGY AB - Field studies were conducted near Lewiston–Woodville and Rocky Mount, NC to evaluate the effects of mixed weed species on peanut yield. A combination of broadleaf and grass weeds were allowed to interfere with peanut for various intervals to determine both the critical timing of weed removal and the critical weed-free period. These periods were then combined to determine the critical period of weed control in peanut. The effects of various weedy intervals on peanut yield were also investigated. The predicted critical period of weed control, in the presence of a mixed population of weeds, was found to be from 3 to 8 wk after planting (WAP). Peanut yield decreased as weed interference intervals increased, demonstrating the need for weed control throughout much of the growing season in the presence of mixed weed populations.Nomenclature: Peanut, Arachis hypogaea L DA - 2008/// PY - 2008/// DO - 10.1614/wt-07-052.1 VL - 22 IS - 1 SP - 63-67 SN - 1550-2740 KW - critical period of weed removal KW - critical time of weed removal KW - critical weed free period KW - weed competition KW - weed interference ER - TY - JOUR TI - Critical period of grass vs. broadleaf weed interference in peanut AU - Everman, Wesley J. AU - Burke, Ian C. AU - Clewis, Scott B. AU - Thomas, Walter E. AU - Wilcut, John W. T2 - WEED TECHNOLOGY AB - Studies were conducted to evaluate the effects of grass and broadleaf weeds on peanut growth and peanut yield. In separate studies, grass or broadleaf weeds were allowed to compete with peanut for various intervals to determine both the critical timing of weed removal and the critical weed-free period. Hand-weeding and selective herbicides were used at appropriate times to remove and terminate weed growth. These periods were then used to determine the critical period of weed control. The effects of various weedy intervals on peanut yield were also investigated. The critical period of grass weed control was found to be from 4.3 to 9 wk after planting (WAP), whereas the critical period of broadleaf weed control was from 2.6 to 8 WAP. Peanut yields decreased as weed interference intervals for both grass and broadleaf weeds increased, demonstrating the need for control of both grass and broadleaf weeds throughout much of the growing season.Nomenclature: Peanut, Arachis hypogaea L DA - 2008/// PY - 2008/// DO - 10.1614/wt-07-037.1 VL - 22 IS - 1 SP - 68-73 SN - 1550-2740 KW - critical period of weed removal KW - critical time of weed removal KW - critical weed-free period KW - weed competition KW - weed interference ER - TY - JOUR TI - Aquatic plant management and the impact of emerging herbicide resistance issues AU - Richardson, Robert J. T2 - WEED TECHNOLOGY AB - Aquatic plants provide many benefits to the environment, but must be managed when growth reaches nuisance levels or when invasive plant species are released. Management tactics include biological, chemical, cultural, mechanical, and physical tools. Each specific management technique has advantages and disadvantages. In addition, the implementation of these techniques can become complicated because of the multiple users, managers, and stakeholders that may be present on large bodies of water. As an example, hydrilla is the most economically damaging aquatic weed in the United States. It reproduces through fragmentation, turions, and occasionally seed and can colonize a wide variety of aquatic environments. The most common management tactics for hydrilla include biological, chemical, and mechanical tools. Triploid grass carp have been the primary biological control agent, whereas fluridone has been the only systemic herbicide used. Because of heavy utilization of fluridone, biotypes have developed resistance to this herbicide in Florida. Although several acetolactate synthase-inhibiting herbicides are in development, herbicides with additional modes of action are needed for resistance management. Other aquatic plant management needs include additional control tactics for algae and additional extension resources for public education.Nomenclature: Fluridone, hydrilla, Hydrilla verticillata (L.f.) Royle, triploid grass carp, Ctenopharyngodon idella Val DA - 2008/// PY - 2008/// DO - 10.1614/wt-07-034.1 VL - 22 IS - 1 SP - 8-15 SN - 1550-2740 KW - Eurasian watermilfoil KW - Myriophyllum spicatum L. KW - Brazilian elodea KW - Egeria densa Planch. KW - brittle naiad KW - Najas KW - minor all KW - Lyngbya spp ER - TY - JOUR TI - Rapid EST isolation from chromosome IR of rye AU - Zhou, Ruo-Nan AU - Shi, Rui AU - Jiang, Shu-Mei AU - Yin, Wei-Bo AU - Wang, Huang-Huang AU - Chen, Yu-Hong AU - Hu, Jun AU - Wang, Richard R. C. AU - Zhang, Xiang-Qi AU - Hu, Zan-Min T2 - BMC PLANT BIOLOGY AB - To obtain important expressed sequence tags (ESTs) located on specific chromosomes is currently difficult. Construction of single-chromosome EST library could be an efficient strategy to isolate important ESTs located on specific chromosomes. In this research we developed a method to rapidly isolate ESTs from chromosome 1R of rye by combining the techniques of chromosome microdissection with hybrid specific amplification (HSA).Chromosome 1R was isolated by a glass needle and digested with proteinase K (PK). The DNA of chromosome 1R was amplified by two rounds of PCR using a degenerated oligonucleotide 6-MW sequence with a Sau3AI digestion site as the primer. The PCR product was digested with Sau3AI and linked with adaptor HSA1, then hybridized with the Sau3AI digested cDNA with adaptor HSA2 of rye leaves with and without salicylic acid (SA) treatment, respectively. The hybridized DNA fragments were recovered by the HSA method and cloned into pMD18-T vector. The cloned inserts were released by PCR using the partial sequences in HSA1 and HSA2 as the primers and then sequenced. Of the 94 ESTs obtained and analyzed, 6 were known sequences located on rye chromosome 1R or on homologous group 1 chromosomes of wheat; all of them were highly homologous with ESTs of wheat, barley and/or other plants in Gramineae, some of which were induced by abiotic or biotic stresses. Isolated in this research were 22 ESTs with unknown functions, probably representing some new genes on rye chromosome 1R.We developed a new method to rapidly clone chromosome-specific ESTs from chromosome 1R of rye. The information reported here should be useful for cloning and investigating the new genes found on chromosome 1R. DA - 2008/3/18/ PY - 2008/3/18/ DO - 10.1186/1471-2229-8-28 VL - 8 SP - SN - 1471-2229 ER - TY - JOUR TI - Evaluation of phosphorus characterization in broiler ileal digesta, manure, and litter samples: P-31-NMR vs. HPLC AU - Leytem, A. B. AU - Kwanyuen, P. AU - Plumstead, P. W. AU - Maguire, R. O. AU - Brake, J. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Abstract Using 31‐phosphorus nuclear magnetic resonance spectroscopy ( 31 P‐NMR) to characterize phosphorus (P) in animal manures and litter has become a popular technique in the area of nutrient management. To date, there has been no published work evaluating P quantification in manure/litter samples with 31 P‐NMR compared to other accepted methods such as high performance liquid chromatography (HPLC). To evaluate the use of 31 P‐NMR to quantify myo ‐inositol hexa kis phosphate (phytate) in ileal digesta, manure, and litter from broilers, we compared results obtained from both 31 P‐NMR and a more traditional HPLC method. The quantification of phytate in all samples was very consistent between the two methods, with linear regressions having slopes ranging from 0.94 to 1.07 and r 2 values of 0.84 to 0.98. We compared the concentration of total monoester P determined with 31 P‐NMR with the total inositol P content determined with HPLC and found a strong linear relationship between the two measurements having slopes ranging from 0.91 to 1.08 and r 2 values of 0.73 to 0.95. This suggests that 31 P‐NMR is a very reliable method for quantifying P compounds in manure/litter samples. DA - 2008/// PY - 2008/// DO - 10.2134/jeq2007.0134 VL - 37 IS - 2 SP - 494-500 SN - 1537-2537 ER - TY - JOUR TI - Transcriptional and post-transcriptional enhancement of gene expression by the 5 ' UTR intron of rice rubi3 gene in transgenic rice cells AU - Samadder, Partha AU - Sivamani, Eltunalai AU - Lu, Jianli AU - Li, Xianggan AU - Qu, Rongda T2 - MOLECULAR GENETICS AND GENOMICS DA - 2008/4// PY - 2008/4// DO - 10.1007/s00438-008-0323-8 VL - 279 IS - 4 SP - 429-439 SN - 1617-4623 KW - EJC KW - exon KW - gene expression KW - IME KW - nuclear run-on ER - TY - JOUR TI - Mapping genes encoding microsomal omega-6 desaturase enzymes and their cosegregation with QTL affecting oleate content in soybean AU - Bachlava, Eleni AU - Dewey, Ralph E. AU - Auclair, Jerome AU - Wang, Sanbao AU - Burton, Joseph W. AU - Cardinal, Andrea J. T2 - CROP SCIENCE AB - The microsomal ω‐6 desaturase enzymes, which catalyze the desaturation of oleic acid to linoleic acid during fatty acid biosynthesis, are encoded by the FAD2‐1 and FAD2‐2 genes in soybean [ Glycine max (L.) Merr.]. Breeders aim to incorporate the high‐oleate trait into soybean germplasm in order to improve the nutritional value and oxidative stability of soybean oil. The objectives of this study were to map the isoforms of the FAD2‐1 and FAD2‐2 genes and investigate the association of these genetic loci with the oleate phenotype in three populations segregating for oleate content. The populations were grown in replicated multienvironment field trials. According to linkage analysis conducted for two of the populations, FAD2‐1A and FAD2‐1B mapped on Linkage Groups O and I, respectively, while the closely linked FAD2‐2A and FAD2‐2B isoforms mapped on Linkage Group L. Oleate quantitative trait loci with minor effects were detected in the proximity of FAD2‐1B and possibly FAD2‐2B on Linkage Groups I and L. Quantitative trait loci affecting maturity were also detected on chromosomal regions adjacent to the FAD2 genes. The genotyping assays developed for the FAD2‐1A , FAD2‐1B , and FAD2‐2B isoforms, as well as their linked simple sequence repeat markers, can be used in soybean breeding programs for the elevation of oleic acid seed content through marker‐assisted selection. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.07.0381 VL - 48 IS - 2 SP - 640-650 SN - 1435-0653 ER - TY - JOUR TI - Heterotic effects in topcrosses of modern and obsolete cotton cultivars AU - Campbell, B. T. AU - Bowman, D. T. AU - Weaver, D. B. T2 - CROP SCIENCE AB - Historically, reselection, pedigree, and mass‐selection breeding methods have been used to develop open‐pollinated cultivars of upland cotton ( Gossypium hirsutum L.). As a result, modern cotton cultivars should have accumulated additive genetic effects with time, while also possessing fewer nonadditive gene effects than obsolete cultivars. A topcross test was conducted to compare the heterotic effects of obsolete and modern cultivars for yield, yield components, and fiber quality. Significant differences were detected between heterosis values for the modern and obsolete cultivar groups for seed cotton yield, lint yield, lint percentage, and boll weight. No significant heterotic effects were detected for fiber quality. The obsolete group of cultivars showed average lint yield heterosis values of 34% compared with 23% for the modern cultivars. Both cultivar groups displayed significant, but similar heterosis values for the number of bolls per square meter (17 and 15%, respectively). The major yield component associated with lint yield heterosis for both groups was bolls per square meter, although boll weight heterosis also contributed to lint yield heterosis for the obsolete cultivars. Although modern cultivars produced considerable heterotic effects for yield, this study demonstrates that obsolete cultivars may provide an additional source of nonadditive genetic effects that can be exploited in a hybrid production system. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.06.0362 VL - 48 IS - 2 SP - 593-600 SN - 0011-183X ER - TY - JOUR TI - Estimating the individual effects of the reduced palmitic acid fap(nc) and fap1 alleles on agronomic traits in two soybean populations AU - Cardinal, Andrea J. AU - Dewey, Ralph E. AU - Burton, Joseph W. T2 - CROP SCIENCE AB - Major fap alleles that reduce palmitate content in soybean [ Glycine max (L.) Merr.] seed oil also can reduce seed yield. One of these alleles, fap nc , has been shown to be a deletion in the GmFATB1a gene. Allele‐specific primers that amplify GmFATB1a can be used to test precisely if the fap nc allele has an effect on agronomic traits. The objectives of this study were to determine if the segregation of the fap nc allele explained a significant amount of genetic variation in several agronomic traits; to determine if the fap1 allele or minor palmitate genes have an effect on agronomic traits; and to confirm if GmFATB1a maps to the distal region on linkage group A1. GmFATB1a ‐specific primers were used to genotype lines from two populations segregating for fap nc , fap1, and fan alleles and modifier genes. The fap nc allele explained a significant portion of the genetic variation in seed yield, plant height, protein content, and stearic acid content in both populations. After removing the effect of fap nc from the model, the genetic correlation between palmitate and yield was significant in one population but not significant between palmitate and height, indicating that fap1 has a small but significant effect on seed yield but no effect on plant height. The fap1 and/or modifier genes significantly affected stearic acid content. GmFATB1a mapped 20 cM distal to Satt684 on linkage group A1. Breeding efforts did not totally eliminate the negative influence of the fap nc allele on seed yield and plant height. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.05.0251 VL - 48 IS - 2 SP - 633-639 SN - 1435-0653 ER - TY - JOUR TI - Effect of feeding corn, hull-less or hulled barley on fermentation by mixed cultures of ruminal microorganisms AU - Fellner, V. AU - Burns, J. C. AU - Marshall, D. S. T2 - JOURNAL OF DAIRY SCIENCE AB - Increased demands for corn grain warrant the evaluation of alternative grain types for ruminant production systems. This study was conducted to determine the effects of hulled and hull-less barley (Hordeum vulgare L.) cultivars compared with corn (Zea mays L.) as an alternative grain type on fermentation in cultures of mixed ruminal microorganisms. Three continuous fermentors were fed 14 g of dry feed per day (divided equally between 2 feedings) consisting of alfalfa (Medicago sativa L.) hay pellets (40% of dry matter) and 1) ground corn, 2) hulled barley, or 3) hull-less barley concentrate (60% of dry matter) in each fermentor. Following an adaptation period of 5 d, culture samples were taken at 2 h after the morning feeding on d 6, 7, and 8 of each period for analysis. A second run of the fermentors followed the same treatment sequence to provide replication. Culture pH was reduced with corn (5.55) and did not differ between barley cultivars (average pH 5.89). Total volatile fatty acid concentration and acetate to propionate ratio were not different across grain type or barley cultivar with the exception of greater total volatile fatty acid concentrations with hull-less barley. Corn produced less methane (14.6 mmol/d) and ammonia-N (7.3 mg/100 mL) compared with barley (33.1 mmol/d and 22 mg/100 mL, respectively); methane was greater with hull-less barley but ammonia-N concentration was similar between the 2 barley cultivars. Hull-less barley had greater digestibility compared with hulled barley, and corn had reduced digestibility compared with barley. Concentrations of C18:0 were greater and those of C18:1 and C18:2 lesser in cultures fed hulled and hull-less barley compared with corn. Our data indicate that grain type and barley cultivar have an impact on ruminal fermentation. The lesser starch concentration of barley minimized the drop in culture pH and improved digestibility. DA - 2008/5// PY - 2008/5// DO - 10.3168/jds.2007-0078 VL - 91 IS - 5 SP - 1936-1941 SN - 0022-0302 KW - barley KW - corn KW - ruminal fermentation ER - TY - JOUR TI - Analysis of chlorothalonil and degradation products in soil and water by GC/MS and LC/MS AU - Chaves, Alicia AU - Shea, Damian AU - Danehower, David T2 - CHEMOSPHERE AB - We present a method using gas chromatography (GC) and liquid chromatography (LC) coupled to a mass selective detector to measure concentrations of the fungicide chlorothalonil and several of its metabolites in soil and water. The methods employed solid-phase extraction using a hydrophobic polymeric phase for the isolation of analytes. In lake water, average analyte recoveries ranged from 70% to 110%, with exception of pentachloronitrobenzene that gave low recoveries (23%). The method detection limits were determined to be in the range of 1 and 0.1 μg l−1 for the LC and GC methods, respectively. In soil samples, recoveries ranged from 80% to 95% for 4-hydroxy-2,5,6-trichloroisophthalonitrile (metabolite II) and 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene (metabolite III). Limits of detection (LOD) were 0.05 and 0.02 μg g−1, respectively. Chlorothalonil and other metabolites were analyzed by GC giving recoveries ranging from 54% to 130% with LOD of 0.001−0.005 μg g−1. DA - 2008/3// PY - 2008/3// DO - 10.1016/j.chemosphere.2007.11.015 VL - 71 IS - 4 SP - 629-638 SN - 0045-6535 KW - metabolites KW - LC/MS KW - pesticides KW - Fungicides KW - SPE ER - TY - JOUR TI - Seed nitrogen mobilization in soybean: Effects of seed nitrogen content and external nitrogen fertility AU - Naegle, Erin AU - Kwanyuen, Prachuab AU - Burton, Joseph AU - Carter, Thomas AU - Rufty, Thomas T2 - JOURNAL OF PLANT NUTRITION AB - ABSTRACT Soybean breeding programs have developed genetic lines with relatively low seed protein, which could negatively impact early seedling growth in low fertility conditions commonly encountered in the field. In these experiments, seed protein mobilization and its regulation in situ in soybean lines with different seed protein levels was investigated. The results showed that rates of nitrogen (N) release from cotyledons were much lower with decreasing levels of N in seed. Patterns of proteolysis of the storage proteins glycinin and β -conglycinin and their subunits were not different, but breakdown rates were slower. Seed N release rates increased somewhat when external N was supplied to roots of the developing seedlings, suggesting the involvement of source/sink controls. The effect appeared to be down-stream from proteolysis, as rates of protein breakdown were not altered. The results indicate that low seed protein levels will lead to reduced seedling fitness in low fertility soil conditions unless fertilizer N is applied. DA - 2008/// PY - 2008/// DO - 10.1080/01904160801894921 VL - 31 IS - 2 SP - 367-379 SN - 1532-4087 KW - seed nitrogen release KW - seed nitrogen transport KW - soybean KW - storage protein degradation ER - TY - JOUR TI - Peanut response to planting date and potential of canopy reflectance as an indicator of pod maturation AU - Carley, Danesha S. AU - Jordan, David L. AU - Dharmasri, L. Cecil AU - Sutton, Turner B. AU - Brandenburg, Rick L. AU - Burton, Michael G. T2 - AGRONOMY JOURNAL AB - Determining when to dig peanut ( Arachis hypogea L.) is complicated because of its indeterminate growth habit. Pod mesocarp color is often used an indicator of pod maturation. However, this process is time consuming and is usually based on a relatively small subsample of pods from peanut fields. Research was conducted during 2003–2005 to determine if reflectance of the peanut canopy, using multispectral imaging (350–2500 nm), could be used as an indicator of pod maturation. The cultivars VA 98R and NC‐V 11 were planted beginning in early May through early June during each year with reflectance and the percentage of pods at optimum maturity (percentage of pods with brown or black mesocarp color) determined in mid‐September. The highest yield observed for VA 98R across the 3 yr of the experiment was noted when peanut was planted in mid‐May rather than early or late May or when planted in early June when peanut was dug based on optimum pod maturity using pod mesocarp color. Pod yield for the cultivar NC‐V 11 did not differ when comparing planting dates. For cultivar VA 98R, Pearson's correlations were significant for all bandwidth categories except the normalized difference vegetation index (NDVI) when reflectance was compared with percentage of mature pods. Reflectance for NC‐V 11 was not significant for any of the correlations even though significant differences in the percentage of mature pods were noted in mid September when comparing planting dates. These data suggest that canopy reflectance could potentially aid in predicting pod maturation, but more research is needed to determine feasibility of this approach. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2006.0352 VL - 100 IS - 2 SP - 376-380 SN - 1435-0645 ER - TY - JOUR TI - The interaction of harvesting time of day of switchgrass hay and ruminal degradability of supplemental protein offered to beef steers AU - Huntington, G. B. AU - Burns, J. C. T2 - JOURNAL OF ANIMAL SCIENCE AB - The objective of this study was to evaluate an interaction between harvest at 0600 (AM) vs. 1800 (PM) with high (HI) or low (LO) ruminal degradability of a protein supplement to change voluntary intake, digestion, or N retention by steers offered switchgrass (Panicum virgatum L.) hay. Black steers (255 +/- 14 kg of BW) were blocked by BW, and then randomly assigned (5 steers each) to AM/HI, PM/HI, AM/LO, or PM/LO treatment groups. Steers were group-housed in covered, outdoor pens with individual feeding gates. After adaptation and standardization, intake was measured for 21 d followed by a digestion trial (5 d of total collection). Steers were offered 767 (LO) or 825 (HI) g/d of supplement to provide 268 g of CP/d. Compared with AM, PM had greater (P = 0.01) concentrations of total nonstructural carbohydrate (TNC, 71 vs. 56 g/kg of DM), and lesser concentrations of NDF (760 vs. 770 g/kg of DM, P = 0.02), ADF (417 vs. 427 g/kg of DM, P = 0.02), and CP (55.9 vs. 58.6 g/ kg of DM, P = 0.07). Protein fractions A, B(2), and B(3) were similar for AM and PM, but HI contained more (P < 0.02) A (694 vs. 296 g/kg of protein) and less B(2) (174 vs. 554 g/kg of protein) fraction than LO. Harvest interacted with supplement to increase (P = 0.07) ad libitum digestible DMI for steers offered PM/HI (11.4 g/kg of BW daily) compared with steers offered PM/LO (10.2 g/kg of BW daily), but there was no difference for steers offered AM/LO or AM/HI (10.7 g/kg of BW). Apparent digestibilities of DM (594 vs. 571 g/kg of intake), NDF (591 vs. 562 g/kg of intake), ADF (585 vs. 566 g/kg of intake), and N (651 vs. 632 g/kg of intake) were greater (P < 0.04) for PM than for AM. Apparent digestibility of N was greater (P = 0.02) for HI (652 g/ kg of intake) vs. LO (631 g/kg of intake). Interactions between harvest and supplement for apparent digestibilities of NDF (P = 0.09) and ADF (P = 0.03) were due to no change or an increase in digestibility in response to increased ruminal degradability of supplement in steers offered PM harvest, whereas increased ruminal degradability of supplement decreased digestibility of NDF and ADF in steers offered AM harvest. Treatments did not affect hay intake (3.93 kg/d), N retained (15.8 g/d), or plasma urea N (5.25 mM) during ad libitum intake. Greater TNC in PM vs. AM harvest was not sufficient by itself to increase total voluntary DMI, but greater protein degradability interacted with harvest time to increase ruminal fiber digestibility and digestible DMI of beef steers offered PM vs. AM harvest. DA - 2008/1// PY - 2008/1// DO - 10.2527/jas.2006-701 VL - 86 IS - 1 SP - 159-166 SN - 0021-8812 KW - beef steer KW - protein degradability KW - switchgrass KW - Panicum virgatum ER - TY - JOUR TI - Sustaining plant breeding-national workshop AU - Stuber, Charles W. AU - Hancock, Jim T2 - CROP SCIENCE AB - Sustaining plant breeding was the central theme of a national workshop held in Raleigh, NC, February 8–9, 2007. The workshop was spearheaded by Ann Marie Thro, National Program Staff of USDA‐CSREES, and was co‐hosted by the Departments of Crop Science and Horticultural Science of North Carolina State University. The major catalyst for the meeting was the growing imbalance between the importance of plant breeding to the nation's future versus the steady decline in the national plant breeding investment over the past 20 years. This has led to a significant reduction in the number of public plant breeders in the U.S. and an associated substantial weakening of university education programs in this area (Frey, 1996; Guner and Wehner, 2003; Morris et al., 2006; Price, 1999). Several previous efforts have drawn attention to our nation's declining plant breeding capacity (National Plant Breeding Study, 1994). More recently, a plant breeding workshop held in 2005 at Michigan State University also focused on the decline in numbers of plant breeders in the public arena (Hancock, 2006). However, the message from these efforts was not nationally audible or sustained through the establishment of a dedicated group interested in maintaining plant breeding as a science and profession. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.07.0406spp VL - 48 IS - 1 SP - 25-29 SN - 0011-183X ER - TY - JOUR TI - Quantitative trait loci and epistasis for crown freezing tolerance in the 'Kanota' x 'Ogle' hexaploid oat mapping population AU - Wooten, David R. AU - Livingston, David P., III AU - Holland, James B. AU - Marshall, David S. AU - Murphy, J. Paul T2 - CROP SCIENCE AB - Crown freezing tolerance is the most important factor conferring oat ( Avena spp.) winter hardiness. The objective of this study was to identify quantitative trait loci (QTL) for crown freezing tolerance in the ‘Kanota’ × ‘Ogle’ recombinant inbred line (RIL) mapping population and to examine their relationship with other winter hardiness traits. One hundred thirty‐five RILs were evaluated for crown freezing tolerance in a controlled environment. Previously published molecular marker and linkage map information was used for QTL detection. Seven QTL and four complementary epistatic interactions were identified that accounted for 56% of the phenotypic variation. Ogle contributed alleles for increased crown freezing tolerance at three loci, while Kanota contributed alleles for increased crown freezing tolerance at four loci. All loci where Kanota alleles increased crown freezing tolerance showed complementary epistasis for decreased crown freezing tolerance with the QTL near UMN13. Two of the major QTL identified were in the linkage groups (LG) associated with a reciprocal translocation between chromosomes 7C and 17, which was previously associated with spring growth habit in oat. The results confirm the importance of the chromosomes involved in the reciprocal 7C‐17 translocation in controlling winter hardiness component traits. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2006.12.0793 VL - 48 IS - 1 SP - 149-157 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35348818142&partnerID=MN8TOARS ER - TY - JOUR TI - Evaluation of elite exotic maize inbreds for use in temperate breeding AU - Nelson, Paul T. AU - Goodman, Major M. T2 - CROP SCIENCE AB - While maize (Zea mays L.) is a highly diverse species, this diversity is not well represented in U.S. maize production acreage. Increased genetic diversity can be obtained through breeding with exotic germplasm, especially tropical-exotic sources. However, the pool of available tropical germplasm is large and diverse, making choices of tropical parents difficult. The maize breeding program at North Carolina State University has initiated a large-scale screening effort to evaluate elite exotic maize inbreds, most of which are tropical-exotic in origin. Here we report screening results for 88 inbreds obtained from various international breeding programs. These lines were tested in replicated yield trials in North Carolina as 50% exotic topcrosses by crossing them to a single-cross U.S. tester of stiff-stalk (SS) by non-stiff-stalk (NSS) origin. The more promising lines additionally entered 25% tropical topcrosses with SS and NSS testers and were further evaluated in yield-trials. A handful of tropical inbred lines—CML10, CML108, CML157Q, CML274, CML341, CML343, and CML373—performed well overall. It was further determined that topcrossing to a single SS by NSS tester will suffice for initial screening purposes, allowing for elimination of the poorest performing lines. Topcrossing to additional SS and NSS testers may be of value when determining where, in terms of heterotic patterns, the better-performing lines will fit into a breeding program. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.05.0287 VL - 48 IS - 1 SP - 85-92 SN - 1435-0653 ER - TY - JOUR TI - Soil enzyme activities in two forage systems following application of different rates of swine lagoon effluent or ammonium nitrate AU - Lyyemperumal, Kannan AU - Shi, Wei T2 - APPLIED SOIL ECOLOGY AB - Land application of swine lagoon effluent (SLE) to forage production systems is widespread in the southeastern USA and often leads to change in soil properties. Although soil enzymes are crucial to the degradation of soil organic matter and cycling of nutrients, the impacts of SLE application on soil enzyme activities have not been well characterized. We assessed the activities of soil enzymes involved in soil C, N, and P cycling in forage systems 3 years after the termination of three consecutive years of fertilization. Bermudagrass and tall fescue were supplied with SLE or ammonium nitrate (AN) at the rates of 0, 200, 400, and 600 kg plant available N (PAN) ha−1 year−1. The activities of oxidative enzymes (i.e., peroxidase and phenol oxidase) differed between soils amended with SLE versus AN. In soils amended with AN at 600 kg PAN ha−1 year−1, the activities of phenol oxidase and peroxidase were lower than or similar to those in the unfertilized control. In contrast, those activities were stimulated by the application of SLE at the rate of 600 kg PAN ha−1 year−1 except for phenol oxidase in the bermudagrass system. The activities of cellobiohydrolase, β-glucosidase, cellulase, β-glucosaminidase, protease, and acid phosphatase, however, were independent of the source, but varied with the rate of fertilization. In general, the activities of cellobiohydrolase, β-glucosidase, cellulase, β-glucosaminidase, protease, and acid phosphatase in soils with N fertilization at 200 or 400 kg PAN ha−1 year−1 were higher than those in the unfertilized control. But the activities of some hydrolytic enzymes in soils fertilized with 600 kg PAN ha−1 year−1 were similar to or lower than those in the unfertilized control. Non-metric multidimensional scaling (NMS) analysis integrated the activities of eight soil enzymes and showed significant differences between fertilized soils and the unfertilized control and between soils amended with SLE versus AN. These differences in soil integrated enzyme activity were correlated with soil pH (Pearson's correlation coefficient r = 0.76, P < 0.05) rather than with other soil properties. The activities of individual enzymes such as peroxidase, cellulase, and acid phosphatase were also significantly correlated with soil pH. Our results suggested that fertilization-associated change in soil pH could influence the potential activities of soil enzymes in the hay production systems. Application of SLE at 600 kg PAN ha−1 year−1 may be unbeneficial to soil organic matter accumulation and nutrient cycling. DA - 2008/2// PY - 2008/2// DO - 10.1016/j.apsoil.2007.10.001 VL - 38 IS - 2 SP - 128-136 SN - 1873-0272 KW - cellulase KW - forage KW - beta-glucosaminidase KW - peroxidase KW - soil enzyme activity KW - swine lagoon effluent ER - TY - JOUR TI - Scaling soil water characteristics of golf course and athletic field sands from particle-size distribution AU - Arya, Lalit A. AU - Bowman, Daniel C. AU - Thapa, Bir B. AU - Cassel, D. Keith T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - The soil water characteristic (SWC) of sands is an important hydraulic parameter in designing golf courses and athletic fields. A modified version of the Arya–Paris model of the soil water characteristic was adapted to 14 golf course media that contained no to minor amounts of clay and silt. In this model, the particle‐size distribution curve is divided into a number of fractions and the natural pore length, L i (n) , is scaled using the diameter of spherical particles as the length unit. The scaled pore length is given by 2 R i , where n i is the number of spherical particles in the i th fraction, 2 R i is the particle diameter, and α i is the scaling parameter, which is calculated using the relationship log = a + b log n i Although the model adapted well, there were concerns about the sensitivity of predicted SWCs to uncertainties in parameters a and b Consequently, we developed and evaluated a procedure to predict L i (n) directly from straight pore lengths, L i (c) in counterpart cubic close‐packed assemblages of spherical particles, using the relationship log L i (n) = c + d log L i (c) Predicted pressure heads using both procedures were similar with best‐fit parameters. When uncertainties were imposed on Parameters a , b and c , d , however, SWCs using the latter procedure showed far less sensitivity, as measured by the root mean square residuals (RMSRs). In addition, for sand materials grouped together on the basis of similarity in particle‐size distribution and bulk density, replacing individual best‐fit parameters by the group mean parameters did not have significant effects on predicted pressure heads. DA - 2008/// PY - 2008/// DO - 10.2136/sssaj2006.0232 VL - 72 IS - 1 SP - 25-32 SN - 0361-5995 ER - TY - JOUR TI - Pm37, a new broadly effective powdery mildew resistance gene from Triticum timopheevii AU - Perugini, L. D. AU - Murphy, J. P. AU - Marshall, D. AU - Brown-Guedira, G. T2 - THEORETICAL AND APPLIED GENETICS DA - 2008/2// PY - 2008/2// DO - 10.1007/s00122-007-0679-x VL - 116 IS - 3 SP - 417-425 SN - 1432-2242 ER - TY - JOUR TI - Ozone and density affect the response of biomass and seed yield to elevated CO2 in rice AU - Reid, Chantal D. AU - Fiscus, Edwin L. T2 - GLOBAL CHANGE BIOLOGY AB - Abstract Tropospheric O 3 reduces growth and yield of many crop species, whereas CO 2 ameliorates the negative effects of O 3 . Thus, in a combined elevated CO 2 and O 3 atmosphere, seed yield is at least restored to that of charcoal‐filtered (CF) air at ambient CO 2 . The CO 2 ‐induced yield increase in CF air is highly variable, suggesting other potential resource limitations. To understand such variability in response, we tested that (1) competition for resources precludes some of the CO 2 enhancement on biomass and yield; and (2) O 3 reduces competition in elevated CO 2 . We grew rice ( Oryza sativa L.) at five densities in CF and O 3 ‐fumigated (+O3) air at ambient (A) and elevated [CO 2 ] (+CO2) in 1997 and 1998. O 3 reduced biomass by 25% and seed yield by 13–20% in A, but had little effect in +CO2. A competition model of biomass and yield response to density based on resource availability without competition showed that fewer resources were used for biomass in +O3 than in CF (average 53% vs. 70%) in A, while in +CO2 85% of resources were used for biomass regardless of O 3 suggesting greater depletion of resources. The enhanced biomass response to CO 2 with O 3 is consistent with a 22% greater CO 2 enhancement ratio [mass in +CO2 air/mass in A air; enhancement ratio (ER)] in +O3 than in CF air. For seed yield, few resources were used (average 17% and 25% for CF in 1997 and 1998, respectively), and ER was 13% greater in +O3. With competition the rate of change of individual plant biomass to density was not affected by +CO2 in CF air in 1997 but was increased 19% with more nutrients in 1998, indicating resource limitations with +CO2. The rate of change of individual plant yield to density was reduced with CO 2 in 1997 and unchanged in 1998 showing a different response to resource limitation for reproductive biomass. The resource use in +O3‐A suggested that increased density and soil fertility might compensate for pollutant damage. Although ambient [O 3 ] can modulate the response to elevated CO 2 , resource limitation precludes the CO 2 fertilization impact and both factors need consideration for better management and forecasts of future productivity. DA - 2008/1// PY - 2008/1// DO - 10.1111/j.1365-2486.2007.01472.x VL - 14 IS - 1 SP - 60-76 SN - 1365-2486 KW - competition model KW - CO(2)x O-3 interaction KW - density KW - nutrients KW - Oryza sativa KW - resource use ER - TY - JOUR TI - Molecular interactions and functionality of a cold-gelling soy protein isolate AU - Cramp, G. L. AU - Kwanyuen, P. AU - Daubert, C. R. T2 - JOURNAL OF FOOD SCIENCE AB - A soy protein isolate (SPI) was thermally denatured at a critical concentration of 8% protein for 3 h at 95 degrees C, resulting in a powder that was readily reconstituted at ambient temperature and that demonstrated improved heat stability and cold-set gel functionality when compared to a control SPI. When SPI was heated at 3% protein equivalently, prior to reconstitution to 8% protein, the final viscosity was about 3 orders of magnitude less than the original sample. The viscosity of SPI heated at 3% protein was still nearly 2 orders of magnitude less than the original sample after both samples were reheated at 8% protein. These results suggested that heat denaturation at low protein concentrations limited network formation even after the protein concentration and interaction sites increased, impacting the isolate's cold gelling ability. Gelation was prevented upon treatment of SPI with iodoacetamide, which carbaminomethylated the cysteine residues, establishing the role of disulfide bonds in network formation. The viscosity of the 8% protein dispersion was also reduced by 2 orders of magnitude when treated with 8 M urea, and when combined with 10 mM DTT the gel viscosity was decreased by another order of magnitude. These results suggested that hydrophobic interactions played a primary role in gel strength after disulfide bonds form. The need for a higher concentration of protein during the heating step indicated that the critical disulfide bonds are intermolecular. Ultimately, the functionality produced by these protein-protein interactions produced a powdered soy protein isolate ingredient with consistent cold-set and thermal gelation properties. DA - 2008/// PY - 2008/// DO - 10.1111/j.1750-3841.2007.00583.x VL - 73 IS - 1 SP - E16-E24 SN - 1750-3841 KW - cold-gelling KW - critical concentration KW - disulfide bonds KW - hydrophobic interactions KW - soy protein isolate ER - TY - JOUR TI - Genetic design and statistical power of nested association mapping in maize AU - Yu, Jianming AU - Holland, James B. AU - McMullen, Michael D. AU - Buckler, Edward S. T2 - GENETICS AB - Abstract We investigated the genetic and statistical properties of the nested association mapping (NAM) design currently being implemented in maize (26 diverse founders and 5000 distinct immortal genotypes) to dissect the genetic basis of complex quantitative traits. The NAM design simultaneously exploits the advantages of both linkage analysis and association mapping. We demonstrated the power of NAM for high-power cost-effective genome scans through computer simulations based on empirical marker data and simulated traits with different complexities. With common-parent-specific (CPS) markers genotyped for the founders and the progenies, the inheritance of chromosome segments nested within two adjacent CPS markers was inferred through linkage. Genotyping the founders with additional high-density markers enabled the projection of genetic information, capturing linkage disequilibrium information, from founders to progenies. With 5000 genotypes, 30–79% of the simulated quantitative trait loci (QTL) were precisely identified. By integrating genetic design, natural diversity, and genomics technologies, this new complex trait dissection strategy should greatly facilitate endeavors to link molecular variation with phenotypic variation for various complex traits. DA - 2008/1// PY - 2008/1// DO - 10.1534/genetics.107.074245 VL - 178 IS - 1 SP - 539-551 SN - 1943-2631 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-40849089396&partnerID=MN8TOARS ER - TY - JOUR TI - Yield, quality, and fruit distribution in Bollgard/Roundup ready and Bollgard II/Roundup ready flex cottons AU - Mills, Cory I. AU - Bednarz, Craig W. AU - Ritchie, Glen L. AU - Whitaker, Jared R. T2 - AGRONOMY JOURNAL AB - New transgenic cotton ( Gossypium hirsutum L.) technologies Bollgard II/Roundup Ready Flex (BGII/RRF) provide additional mechanisms for the cotton crop to retain early initiated fruiting structures positioned in the lower canopy. It may be possible, therefore, for early fruit retention to become too high with these new technologies resulting in early cutout and reduced yield. The objective of this investigation was to determine if glyphosate‐induced differences in early season retention occur between BGII/RRF and the older Bollgard/Roundup Ready (BG/RR) technologies and if so, to test if these differences in retention impact crop maturity, yield, or quality under irrigated and nonirrigated conditions. A study was conducted in 2004 and 2005 at two locations in southwestern Georgia to compare the two technologies under dryland vs. irrigation with or without flower removal. The BG/RR matured later than BGII/RRF when glyphosate was applied late at the seventh and 11th leaf stages. The BG/RR compensated for fruit loss by producing heavier remaining bolls. The BGII/RRF maturity was unaffected by the late glyphosate applications and produced a higher percentage of plants having a harvestable boll in the lower canopy than BG/RR. The BGII/RRF cotton had increased boll number and weight at the first sympodial position at lower main stem nodes while BG/RR produced more and heavier bolls on upper main stem nodes. Flower removal did not negatively affect BGII/RRF or BG/RR yields. Few differences in fiber quality were observed. The BGII/RRF retained more early reproductive structures than BG/RR but also cutout earlier. Yield differences between the two technologies may be due to agronomic performance of the variety backgrounds used. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2006.0299 VL - 100 IS - 1 SP - 35-41 SN - 0002-1962 ER - TY - JOUR TI - XND1, a member of the NAC domain family in Arabidopsis thaliana, negatively regulates lignocellulose synthesis and programmed cell death in xylem AU - Zhao, Chengsong AU - Avci, Utku AU - Grant, Emily H. AU - Haigler, Candace H. AU - Beers, Eric P. T2 - PLANT JOURNAL AB - Members of the large Arabidopsis NAC domain transcription factor family are regulators of meristem development, organ elongation and separation, and deposition of patterned secondary cell walls. XYLEM NAC DOMAIN 1 (XND1) is highly expressed in xylem. Changes observed for XND1 knockout plants compared with wild-type Arabidopsis thaliana included a reduction in both plant height and tracheary element length and an increase in metaxylem relative to protoxylem in roots of plants treated with the proteasome inhibitor MG132. Overexpression of XND1 resulted in extreme dwarfism associated with the absence of xylem vessels and little or no expression of tracheary element marker genes. In contrast, phloem marker-gene expression was not altered and phloem-type cells still formed. Transmission electron microscopy showed that parenchyma-like cells in the incipient xylem zone in hypocotyls of XND1 overexpressors lacked secondary wall thickenings and retained their cytoplasmic content. Considered together, these findings suggest that XND1 affects tracheary element growth through regulation of secondary wall synthesis and programmed cell death. DA - 2008/2// PY - 2008/2// DO - 10.1111/j.1365-313X.2007.03350.x VL - 53 IS - 3 SP - 425-436 SN - 0960-7412 KW - Arabidopsis KW - xylem KW - tracheary element KW - cell wall KW - programmed cell death KW - NAC domain ER - TY - JOUR TI - Winter wheat blends (mixtures) produce a yield advantage in north Carolina AU - Cowger, Christina AU - Weisz, Randy T2 - AGRONOMY JOURNAL AB - Seed mixtures, or blends, of small grain cultivars are unknown in eastern U.S. wheat production, where numerous diseases and abiotic stresses often reduce yield and quality. In 2004–2005 and 2005–2006, a field experiment was conducted at Kinston, Plymouth, and Salisbury, NC, to compare performance of eight soft red winter wheat ( Triticum aestivum L.) cultivars having a range of maturities with that of 13 blends, each consisting of equal proportions of two or three of the cultivars. The blends were composed to have complementary disease resistance traits. Disease pressure was at most moderate in any environment. Blends significantly outyielded the means of their respective components (midcomponents) in Plymouth in 2005 ( P = 0.042) and across all environments ( P = 0.039), with a mean overall blend advantage of 0.13 Mg ha −1 . Averaged across environments, two blends significantly outyielded their midcomponents ( P ≤ 0.011). Yield stability of blends exceeded that of pure cultivars by the stability variance model and principal component analysis. In general, blends did not differ significantly from midcomponents for test weight ( P = 0.37), protein content ( P = 0.10), hardness ( P = 0.68), or falling number (sprouting tolerance, P = 0.89), but seed diameter nonuniformity of blends exceeded that of midcomponents ( P = 0.0002). Wheat blends may offer a small yield advantage to North Carolina growers even in the absence of severe disease. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2007.0128 VL - 100 IS - 1 SP - 169-177 SN - 1435-0645 ER - TY - JOUR TI - Soil chemical and microbiological properties in hay production systems: residual effects of contrasting N fertilization of swine lagoon effluent versus ammonium nitrate AU - Iyyemperumal, Kannan AU - Green, James, Jr. AU - Israel, Daniel W. AU - Ranells, Noah N. AU - Shi, Wei T2 - BIOLOGY AND FERTILITY OF SOILS DA - 2008/2// PY - 2008/2// DO - 10.1007/s00374-007-0221-y VL - 44 IS - 3 SP - 425-434 SN - 1432-0789 KW - microbial biomass KW - C and N mineralization KW - amino sugar N KW - forage KW - swine lagoon effluent ER - TY - JOUR TI - Evaluation of tobacco germplasm for seedling resistance to stem rot and target spot caused by Thanatephorus cucumeris AU - Elliott, P. E. AU - Lewis, R. S. AU - Shew, H. D. AU - Gutierrez, W. A. AU - Nicholson, J. S. T2 - PLANT DISEASE AB - Stem rot and target spot of tobacco, caused by Rhizoctonia solani and its teleomorph Thanatephorus cucumeris, respectively, can cause serious problems in production of tobacco (Nicotiana tabacum) seedlings. Previous screens for genetic resistance in tobacco have been limited. The objective of this study was to evaluate 97 genotypes composing several classes of tobacco and related Nicotiana spp. for seedling resistance to stem rot and target spot. Significant differences in disease incidence initially were observed among the genotypes for both stem rot and target spot; however, resistance to target spot was not observed when disease pressure was high. Partial resistance to stem rot was observed in several genotypes in repeated tests. These accessions may be useful as a source of resistance to R. solani in future breeding efforts. DA - 2008/3// PY - 2008/3// DO - 10.1094/PDIS-92-3-0425 VL - 92 IS - 3 SP - 425-430 SN - 0191-2917 ER - TY - JOUR TI - Xenopus microRNA genes are predominantly located within introns and are diffferentially expressed in adult frog tissues via post-transcriptional regulation AU - Tang, Guo-Qing AU - Maxwell, E. Stuart T2 - GENOME RESEARCH AB - The amphibian Xenopus provides a model organism for investigating microRNA expression during vertebrate embryogenesis and development. Searching available Xenopus genome databases using known human pre-miRNAs as query sequences, more than 300 genes encoding 142 Xenopus tropicalis miRNAs were identified. Analysis of Xenopus tropicalis miRNA genes revealed a predominate positioning within introns of protein-coding and nonprotein-coding RNA Pol II-transcribed genes. MiRNA genes were also located in pre-mRNA exons and positioned intergenically between known protein-coding genes. Many miRNA species were found in multiple locations and in more than one genomic context. MiRNA genes were also clustered throughout the genome, indicating the potential for the cotranscription and coordinate expression of miRNAs located in a given cluster. Northern blot analysis confirmed the expression of many identified miRNAs in both X. tropicalis and X. laevis. Comparison of X. tropicalis and X. laevis blots revealed comparable expression profiles, although several miRNAs exhibited species-specific expression in different tissues. More detailed analysis revealed that for some miRNAs, the tissue-specific expression profile of the pri-miRNA precursor was distinctly different from that of the mature miRNA profile. Differential miRNA precursor processing in both the nucleus and cytoplasm was implicated in the observed tissue-specific differences. These observations indicated that post-transcriptional processing plays an important role in regulating miRNA expression in the amphibian Xenopus. DA - 2008/1// PY - 2008/1// DO - 10.1101/gr.6539108 VL - 18 IS - 1 SP - 104-112 SN - 1549-5469 ER - TY - JOUR TI - Sensible heat observations reveal soil-water evaporation dynamics AU - Heitman, J. L. AU - Horton, R. AU - Sauer, T. J. AU - Desutter, T. M. T2 - JOURNAL OF HYDROMETEOROLOGY AB - Abstract Soil-water evaporation is important at scales ranging from microbial ecology to large-scale climate. Yet routine measurements are unable to capture rapidly shifting near-surface soil heat and water processes involved in soil-water evaporation. The objective of this study was to determine the depth and location of the evaporation zone within soil. Three-needle heat-pulse sensors were used to monitor soil heat capacity, thermal conductivity, and temperature below a bare soil surface in central Iowa during natural wetting/drying cycles. Soil heat flux and changes in heat storage were calculated from these data to obtain a balance of sensible heat components. The residual from this balance, attributed to latent heat from water vaporization, provides an estimate of in situ soil-water evaporation. As the soil dried following rainfall, results show divergence in the soil sensible heat flux with depth. Divergence in the heat flux indicates the location of a heat sink associated with soil-water evaporation. Evaporation estimates from the sensible heat balance provide depth and time patterns consistent with observed soil-water depletion patterns. Immediately after rainfall, evaporation occurred near the soil surface. Within 6 days after rainfall, the evaporation zone proceeded &gt; 13 mm into the soil profile. Evaporation rates at the 3-mm depth reached peak values &gt; 0.25 mm h−1. Evaporation occurred simultaneously at multiple measured depth increments, but with time lag between peak evaporation rates for depths deeper below the soil surface. Implementation of finescale measurement techniques for the soil sensible heat balance provides a new opportunity to improve understanding of soil-water evaporation. DA - 2008/2// PY - 2008/2// DO - 10.1175/2007JHM963.1 VL - 9 IS - 1 SP - 165-171 SN - 1525-755X ER - TY - JOUR TI - Influence of Mehlich-3 extractable aluminum on phosphorus retention in organic soils AU - Dell'Olio, Laura A. AU - Maguire, Rory O. AU - Osmond, Deanna L. T2 - SOIL SCIENCE AB - Phosphorus (P) regulations in North Carolina (NC) assume that organic soils have little ability to retain P, and losses of P from these soils are of concern for the health of aquatic ecosystems. However, recent research has indicated decreased water-soluble P (WSP) in organic soils in the presence of high Al concentrations. Our objectives were to determine (i) the concentrations of organic matter (OM), and Mehlich-3 Al and Fe in deep and shallow organic soils in NC, and (ii) how these factors affect P retention. We sampled four organic soil series and determined Mehlich-3 P, Al, and Fe (M3P, M3Al, M3Fe), WSP, total P, pH, particle size distribution, and OM. Water-soluble P and M3P were also measured in a 21-day incubation study, in which P was added at a rate equivalent to 150 kg P ha−1. The main cation responsible for P retention was Al, and the mean topsoil M3Al concentrations (1926 mg kg−1) in these organic soils were close to three times higher than those observed in another study of mostly mineral NC soils. Mehlich-3 Fe was not significantly related to WSP. Retention of added P was negatively related to OM and positively related to M3Al. The ratio of OM and M3Al was the best predictor of WSP and retention of added P. The results from this study indicate that organic soils can retain P more strongly than previously thought, and their ability to retain P is best described by the ratio of OM and M3Al. DA - 2008/2// PY - 2008/2// DO - 10.1097/ss.0b013e31815d8eb7 VL - 173 IS - 2 SP - 119-129 SN - 1538-9243 KW - aluminum KW - organic matter KW - phosphorus ER - TY - JOUR TI - Expression of the bacteriophage T4 lysozyme gene in tall fescue confers resistance to gray leaf spot and brown patch diseases AU - Dong, Shujie AU - Shew, H. David AU - Tredway, Lane P. AU - Lu, Jianli AU - Sivamani, Elumalai AU - Miller, Eric S. AU - Qu, Rongda T2 - TRANSGENIC RESEARCH DA - 2008/2// PY - 2008/2// DO - 10.1007/s11248-007-9073-3 VL - 17 IS - 1 SP - 47-57 SN - 1573-9368 KW - fungal resistance KW - Magnaporthe grisea KW - Rhizoctonia solani KW - T4 lysozyme KW - tall fescue ER - TY - JOUR TI - CYP82E4-mediated nicotine to nornicotine conversion in tobacco is regulated by a senescence-specific signaling pathway AU - Chakrabarti, Manohar AU - Bowen, Steven W. AU - Coleman, Nicholas P. AU - Meekins, Karen M. AU - Dewey, Ralph E. AU - Siminszky, Balazs T2 - PLANT MOLECULAR BIOLOGY DA - 2008/3// PY - 2008/3// DO - 10.1007/s11103-007-9280-6 VL - 66 IS - 4 SP - 415-427 SN - 1573-5028 KW - alkaloid KW - cytochrome P450 KW - SAG KW - senescence-associated gene KW - stress KW - transcriptional regulation ER -