TY - SOUND TI - New Turfgrasses AU - Miller, Grady L. DA - 2001/3/21/ PY - 2001/3/21/ ER - TY - JOUR TI - Evaluation of NIRS and multispectrum radiometry for turfgrass nutrient analysis AU - Thomas, A.P. AU - Miller, G.L. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 8 ER - TY - SOUND TI - Torpedograss photosynthetic response following Drive, Illoxan, and Drive + Illoxan AU - Weinbrecht, Jan S. AU - Edenfield, Jeff T. AU - Miller, Grady L. DA - 2001/3/7/ PY - 2001/3/7/ ER - TY - JOUR TI - Biology and management of tropical signalgrass (Urochloa subquadripara) AU - Teuton, T.C. AU - Brecke, B.J. AU - Unruh, J.B. AU - McDonald, G.E. AU - Ducar, J.T. AU - Miller, G.L. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 7 ER - TY - JOUR TI - Compost utilization along Florida roadways AU - Harrell, M.S. AU - Miller, G.L. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 5 ER - TY - SOUND TI - Biology and management of tropical signalgrass AU - Teuton, Travis C. AU - Brecke, Barry J. AU - Unruh, J.Bryan AU - McDonald, Greg AU - Ducar, Joyce T. AU - Miller, Grady L. DA - 2001/7// PY - 2001/7// ER - TY - JOUR TI - Influence of crumb rubber and porous ceramic on turf performance subjected to wear AU - Miller, G.L. AU - Weinbrecht, J.S. AU - Morgan, M. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 17 ER - TY - JOUR TI - Torpedograss (Panicum repens) photosynthetic response following Drive, Illoxan, and Drive plus Illoxan AU - Weinbrecht, J.S. AU - Edenfield, J.T. AU - Miller, G.L. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 9–10 ER - TY - SOUND TI - Shade effects on growth parameters of ultradwarf bermudagrass maintained at two mowing heights. AU - Edenfield, Jeff T. AU - Miller, Grady L. AU - Nagata, Russell T. AU - McDonald, Greg DA - 2001/3/7/ PY - 2001/3/7/ ER - TY - JOUR TI - Light intensity effects on growth parameters on ultradwarf bermudagrass maintained at two mowing heights AU - Edenfield, J.T. AU - Miller, G.L. AU - Nagata, R.T. AU - McDonald, G. T2 - UF-IFAS Turfgrass Field Days Program Abstracts DA - 2001/// PY - 2001/// SP - 4 ER - TY - SOUND TI - Influence of Crumb Rubber and Porous Ceramic on Turf Performance Subjected to Wear. AU - Miller, Grady L. AU - Weinbrecht, Jan S. AU - Morgan, Mitch DA - 2001/3/8/ PY - 2001/3/8/ M3 - UF-IFAS Field Tours ER - TY - SOUND TI - Managing Baseball Turf AU - Miller, Grady L. DA - 2001/10/14/ PY - 2001/10/14/ ER - TY - JOUR TI - Perennial grassy weed screening trials AU - Weinbrecht, J.S. AU - Miller, G.L. T2 - Florida Weed Science DA - 2001/// PY - 2001/// ER - TY - SOUND TI - Design and Management of Baseball Fields AU - Miller, Grady L. DA - 2001/6/19/ PY - 2001/6/19/ ER - TY - JOUR TI - Torpedograss (Panicum repens) efficacy following Drive and Drive plus Illoxan treatments AU - Weinbrecht, J.S. AU - Miller, G.L. AU - McCarty, L.B. T2 - Southern Weed Science DA - 2001/// PY - 2001/// VL - 2 ER - TY - SOUND TI - Design and Management of Baseball Fields AU - Miller, Grady L. DA - 2001/4/5/ PY - 2001/4/5/ ER - TY - RPRT TI - Baseball field layout and construction AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// M1 - ENH-159 M3 - University of Florida Extension Service PB - University of Florida SN - ENH-159 ER - TY - SOUND TI - Managing Grasses for Landscape and Recreational Uses. LEI 3600 Leisure Facilities AU - Miller, Grady L. DA - 2001/10/2/ PY - 2001/10/2/ ER - TY - RPRT TI - Maintaining athletic fields AU - Miller, G.L. AU - Cisar, J.L. A3 - University of Florida DA - 2001/// PY - 2001/// M1 - Bul 262 M3 - University of Florida Extension Service PB - University of Florida SN - Bul 262 ER - TY - SOUND TI - Sports and Turf AU - Miller, Grady L. DA - 2001/11/14/ PY - 2001/11/14/ M3 - Survey Course ER - TY - SOUND TI - Sports and Turf AU - Miller, Grady L. DA - 2001/8/31/ PY - 2001/8/31/ ER - TY - RPRT TI - Florida Sports Turfgrass AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Poa trivialis overseeding rates on FloraDwarf and Tifdwarf and the transitional spring growth response AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - JOUR TI - Light intensity effects on ultradwarf bermudagrass AU - Edenfield, J.T. AU - Miller, G.L. T2 - Golf Course Management DA - 2001/// PY - 2001/// VL - 69 IS - 5 SP - 78 ER - TY - RPRT TI - Season long grassy weed control with various pre-emergence herbicides AU - Miller, G.L. AU - Weinbrecht, J.S. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Phosphorus and potassium fertilizers influence establishment of bermudagrass AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Water and nutrient availability as influenced by a porous ceramic soil amendment AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Turfgrass establishment using a liquid source of phosphorus AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Effluent water influences turfgrass growth compared to potable water AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - UF Publications and the Audubon cooperative sanctuary program AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Influence of two topdressing materials on turf performance subjected to wear AU - Miller, G.L. AU - Weinbrecht, J.S. AU - Morgan, M.M. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Evaluation of soccer field for turf standards AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - RPRT TI - Evaluation of turf damage and traction from athletic shoe cleats AU - Miller, G.L. A3 - University of Florida DA - 2001/// PY - 2001/// PB - University of Florida ER - TY - MGZN TI - The proof is in the plant food AU - Miller, G.L. T2 - TurfNotes DA - 2001/// PY - 2001/// ER - TY - CONF TI - Turf Management AU - Miller, Grady L. T2 - Florida Recreation and Park Association Meeting C2 - 2001/3/14/ CY - Gainesville, FL DA - 2001/3/14/ PY - 2001/3/14/ ER - TY - SOUND TI - Writing Maintenance Specifications for Athletic Fields AU - Miller, Grady L. DA - 2001/12/4/ PY - 2001/12/4/ ER - TY - SOUND TI - Soil amendment use AU - Miller, Grady L. DA - 2001/3/17/ PY - 2001/3/17/ ER - TY - SOUND TI - Using Near Infrared Reflectance Spectroscopy (NIRS) to Determine P, K, Ca, and Mg Concentrations in Bermudagrass AU - Thomas, Adam AU - Miller, G.L DA - 2001/3/7/ PY - 2001/3/7/ ER - TY - SOUND TI - Compost utilization along Florida roadways AU - Harrell, Mike S. AU - Miller, Grady L. DA - 2001/3/7/ PY - 2001/3/7/ ER - TY - CONF TI - Torpedograss photosynthetic response following Drive, Illoxan, and Drive+Illoxan applications. AU - Edenfield, Jeff T. AU - Miller, Grady L. AU - McDonald, Greg AU - Weinbrecht, Jan S. T2 - 24th Annual Weed Science Society Meeting C2 - 2001/2/26/ CY - Gainesville, FL DA - 2001/2/26/ PY - 2001/2/26/ ER - TY - SOUND TI - Turfgrass Studies at University of Florida AU - Miller, Grady L. DA - 2001/5/12/ PY - 2001/5/12/ ER - TY - CONF TI - UF Turfgrass Envirotron Research Update. AU - Miller, Grady L. AU - Weinbrecht, J.S. T2 - 24th Annual Weed Science Society Meeting C2 - 2001/2/26/ CY - Gainesville, FL DA - 2001/2/26/ PY - 2001/2/26/ ER - TY - SOUND TI - Turfgrass and Golf Course Industries AU - Miller, Grady L. DA - 2001/3/1/ PY - 2001/3/1/ ER - TY - CONF TI - Plant Nutrition and Fertilizers, Part II AU - Miller, Grady L. AU - Rieke, P.E. T2 - Golf Course Superintendent's Association C2 - 2001/2/13/ CY - Dallas, Texas DA - 2001/2/13/ PY - 2001/2/13/ ER - TY - SOUND TI - Golf Course Water BMPs AU - Miller, Grady L. DA - 2001/3/17/ PY - 2001/3/17/ ER - TY - CONF TI - Plant Nutrition and Fertilizers, Part I. AU - Miller, Grady L. AU - Rieke, P.E. T2 - Golf Course Superintendent's Association C2 - 2001/2/12/ CY - Dallas, Texas DA - 2001/2/12/ PY - 2001/2/12/ ER - TY - CONF TI - Water relations and rooting characteristics of three Stenotaphrum secundatum grasses grown under deficit irrigation. AU - Miller, Grady L. AU - McCarty, L.B. T2 - International Turfgrass Society meeting C2 - 2001/6/16/ CY - Toronto, Canada DA - 2001/6/16/ PY - 2001/6/16/ ER - TY - CONF TI - Turfgrass Research Units AU - Miller, Grady L. AU - Trenholm, Laurie E. T2 - American Society of Agronomy, Crop Science Society of America, Soil Science Society of America Meetings C2 - 2001/10/23/ CY - Charlotte, North Carolina DA - 2001/10/23/ PY - 2001/10/23/ ER - TY - MGZN TI - Using Athletic Fields AU - Miller, G.L. T2 - Green Industry DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Topdressing with beach sand - too much salt AU - Miller, G.L. T2 - Green Industry DA - 2001/// PY - 2001/// ER - TY - MGZN TI - Coping with Drought AU - Miller, G.L. T2 - Green Industry DA - 2001/// PY - 2001/// ER - TY - MGZN TI - Two for the price of one AU - Miller, G.L. T2 - Green Industry DA - 2001/// PY - 2001/// ER - TY - MGZN TI - Q&A AU - Miller, G.L T2 - Green Industry DA - 2001/// PY - 2001/// UR - http://www.greenindustry.com/st/2001/1200/1200qu.asp ER - TY - CONF TI - Water relations and rooting characteristics of three Stenotaphrum secundatum turf cultivars grown under water deficit conditions AU - Miller, G.L. AU - McCarty, L.B. C2 - 2001/// C3 - Proccedings of the International Turfgrass Society Research Journal CY - Toronto, Canada DA - 2001/// PY - 2001/// VL - 9 SP - 323-328 M1 - 2 ER - TY - JOUR TI - Physiological and morphological response of torpedograss to Drive and Illoxan treatments AU - Edenfield, J.T. AU - Weinbrecht, J.S. AU - Miller, G.L. AU - McDonald, G.E. T2 - Florida Weed Science DA - 2001/// PY - 2001/// SP - 7 –8 ER - TY - JOUR TI - Compost aides turf establishment on steep slopes AU - Harrell, M.S. AU - Miller, G.L. T2 - Golf Course Management DA - 2001/// PY - 2001/// VL - 69 IS - 8 SP - 76 ER - TY - JOUR TI - Cultivation of high-traffic turf AU - Miller, G.L. T2 - Tennessee Turfgrass DA - 2001/2// PY - 2001/2// SP - 12 ER - TY - JOUR TI - Fertilization of high-traffic athletic fields AU - Miller, G.L. T2 - Tennessee Turfgrass. DA - 2001/2// PY - 2001/2// SP - 27 ER - TY - JOUR TI - Potassium for stress resistance AU - Miller, G.L. T2 - Tennessee Turfgrass DA - 2001/8// PY - 2001/8// SP - 30–32 ER - TY - JOUR TI - Teaching golf green construction using lecture, videotape, and scale models in a turfgrass management course AU - Miller, G.L. T2 - NACTA Journal DA - 2001/12// PY - 2001/12// SP - 49–53 SN - 0149-4910 ER - TY - JOUR TI - Potassium rich and stress resistant AU - Miller, G.L. T2 - Florida Turf Digest DA - 2001/// PY - 2001/// VL - 18 IS - 5 SP - 33-35 ER - TY - JOUR TI - Two Pieces of turf equipment help solve turf problems AU - Miller, G.L. T2 - Florida Turf Digest DA - 2001/// PY - 2001/// VL - 18 IS - 3 SP - 39 ER - TY - JOUR TI - Topdressing materials tested for cart wear AU - Miller, G.L. T2 - Florida Turf Digest DA - 2001/// PY - 2001/// VL - 18 IS - 6 SP - 21–22 ER - TY - JOUR TI - Light + nutrients = current research at the "Tron" AU - Miller, G.L. T2 - Florida Turf Digest DA - 2001/// PY - 2001/// VL - 18 IS - 4 SP - 22 ER - TY - JOUR TI - Overseed cultivar, rate affects transition AU - Miller, G.L. AU - Weinbrecht, J.S. T2 - Florida Turf Digest DA - 2001/// PY - 2001/// VL - 18 IS - 1 SP - 18–20 ER - TY - CONF TI - Construction of New Athletic Fields AU - Miller, Grady L. T2 - Hawaii Turfgrass Conference C2 - 2001/10/18/ CY - Oahu, Hawaii DA - 2001/10/18/ PY - 2001/10/8/ ER - TY - SOUND TI - Recent Sports Turf Research. AU - Miller, Grady L. DA - 2001/7/6/ PY - 2001/7/6/ ER - TY - SOUND TI - Sports Turf Q&A AU - Miller, Grady L. AU - Goatley, Mike AU - Samples, Tom AU - McCarty, L.B. DA - 2001/6/7/ PY - 2001/6/7/ ER - TY - CONF TI - Managing Athletic Fields for Improved Traction AU - Miller, Grady L. T2 - Hawaii Turfgrass Conference C2 - 2001/10/17/ CY - Oahu, Hawaii DA - 2001/10/17/ PY - 2001/10/17/ ER - TY - CONF TI - Warm-season weed management for Sports Turf AU - Miller, Grady L. T2 - 12th Annual Sports Turf Managers Association Conference C2 - 2001/1/19/ CY - Tampa, FL DA - 2001/1/19/ PY - 2001/1/19/ ER - TY - CONF TI - New Product AU - Snyder, George AU - Miller, Grady L. T2 - 12th Annual Sports Turf Managers Association Conference C2 - 2001/1/18/ CY - Tampa, FL DA - 2001/1/18/ PY - 2001/1/18/ ER - TY - CONF TI - Inorganic Soil Amendments AU - Miller, Grady L. T2 - 35th Annual Tennessee Turfgrass Conference C2 - 2001/1/4/ CY - Nashville, TN DA - 2001/1/4/ PY - 2001/1/4/ ER - TY - CONF TI - Managing Sports Turf for Improved Footing AU - Miller, Grady L. T2 - 35th Annual Tennessee Turfgrass Conference C2 - 2001/1/4/ CY - Nashville, TN DA - 2001/1/4/ PY - 2001/1/4/ ER - TY - CONF TI - Amending Golf Greens AU - Miller, Grady L. T2 - 49th Annual Florida Turfgrass Association Conference C2 - 2001/8/14/ CY - Gainesville, FL. DA - 2001/8/14/ PY - 2001/8/14/ ER - TY - CONF TI - Aerification and Fertility Practices for Athletic Fields. AU - Miller, Grady L. T2 - 46th Annual Florida Turfgrass Association Conference C2 - 2001/8/14/ CY - Gainesville, FL DA - 2001/8/14/ PY - 2002/8/14/ ER - TY - JOUR TI - Coping with drought AU - Miller, G.L. T2 - SportsTurf DA - 2001/// PY - 2001/// VL - 17 IS - 7 SP - 46 ER - TY - JOUR TI - Using athletic fields AU - Miller, G.L. T2 - SportsTurf DA - 2001/// PY - 2001/// VL - 17 IS - 9 SP - 38 ER - TY - JOUR TI - Inoculation with arbuscular mycorrhizal fungi enhances growth of Litchi chinensis Sonn. trees after propagation by air-layering AU - Janos, D.P. AU - Schroeder, M. AU - Schaffer, B. AU - Crane, J. T2 - Plant and Soil DA - 2001/// PY - 2001/// DO - 10.1023/A:1010329618152 VL - 233 SP - 85–94 KW - glomales KW - mineral nutrition KW - phosphorus fertilization KW - Sapindaceae KW - soil-free medium KW - stem cuttings ER - TY - JOUR TI - Land-use and erosion of a Costa Rican Ultisol affect soil chemistry, mycorrhizal fungi and early regeneration AU - Carpenter, F.Lynn AU - Mayorga, Sergio Palacios AU - Quintero, Eduardo Gonzalez AU - Schroeder, Michelle T2 - Forest Ecology and Management AB - Deforestation causes soil erosion, especially in the humid tropics where rainfall is heavy and terrain is often steep. Land-uses, such as overgrazing and planting annual crops on slopes exacerbate the resultant land degradation. Consequent loss of productivity in this area of the world is on a collision course with increasing human population density and the demand for food. Because of the serious nature of erosion, its effects on tropical soil, especially biological characteristics that help re-establish soil fertility, need more study. Here, we used apparent erosion intensity, land-use history, and soil color to find eight sites representing an a priori spatial gradient of soil degradation on an overgrazed Costa Rican farm. We tested the gradient by measuring several chemical factors that indicate fertility of these tropical Ultisols. These factors decreased with increasing degree of soil degradation. Next, we assessed spore density and diversity of arbuscular mycorrhizal fungi (AMF) along the gradient. We found that the diversity and composition of AMF changed across the gradient although not in the same pattern as the chemical factors. Finally, three years of vegetative regeneration after cattle exclusion had not improved the soils chemically but some improvement in AMF status was suggested for the less damaged sites. These results show that local farmers can use common sense cues to determine the chemical and biological status of their soils, that they can use these cues in future land-use decisions, such as planting hardy trees in the most degraded sites, and that they must expect severely degraded sites to require many years for recuperation. It is possible that intervention to improve the AMF status of soils could hasten recovery, since this process seems to be the first to occur. DA - 2001/4// PY - 2001/4// DO - 10.1016/s0378-1127(00)00361-3 VL - 144 IS - 1-3 SP - 1-17 J2 - Forest Ecology and Management LA - en OP - SN - 0378-1127 UR - http://dx.doi.org/10.1016/s0378-1127(00)00361-3 DB - Crossref KW - rain forest degradation KW - tropical Ultisols KW - arbuscular mycorrhizal fungi (AMF) KW - erosion KW - tropical revegetation KW - tropical degraded pastures KW - Costa Rica ER - TY - JOUR TI - Polymorphism of PCR-based markers targeting exons, introns, promoter regions, and SSRs in maize and introns and repeat sequences in oat AU - Holland, J.B. AU - Helland, S.J. AU - Sharopova, N. AU - Rhyne, D.C. T2 - Genome AB - Sequence databases could be efficiently exploited for development of DNA markers if it were known which gene regions reveal the most polymorphism when amplified by PCR. We developed PCR primer pairs that target specific regions of previously sequenced genes from Avena and Zea species. Primers were targeted to amplify 40 introns, 24 exons, and 23 promoter regions within 54 maize genes. We surveyed 48 maize inbred lines (previously assayed for simple-sequence repeat (SSR) polymorphism) for amplification-product polymorphism. We also developed primers to target 14 SSRs and 12 introns within 18 Avena genes, and surveyed 22 hexaploid oat cultivars and 2 diploid Avena species for amplification-product polymorphism. In maize, 67% of promoter markers, 58% of intron markers, and 13% of exon markers exhibited amplification-product polymorphisms. Among polymorphic primer pairs in maize, genotype diversity was highest for SSR markers (0.60) followed by intron markers (0.46), exon markers (0.42), and promoter markers (0.28). Among all Avena genotypes, 64% of SSR markers and 58% of intron markers revealed polymorphisms, but among the cultivars only, 21% of SSR markers and 50% of intron markers were polymorphic. Polymorphic-sequence-tagged sites for plant-breeding applications can be created easily by targeting noncoding gene regions. DA - 2001/// PY - 2001/// DO - 10.1139/g01-110 VL - 44 IS - 6 SP - 1065-1076 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85047681394&partnerID=MN8TOARS ER - TY - JOUR TI - Blend response and stability and cultivar blending ability in oat AU - Helland, S.J. AU - Holland, J.B. T2 - Crop Science DA - 2001/// PY - 2001/// VL - 41 IS - 6 SP - 1689-1696 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035656793&partnerID=MN8TOARS ER - TY - JOUR TI - A restriction fragment length polymorphism based linkage map of a diploid Avena recombinant inbred line population AU - Kremer, C.A. AU - Lee, M. AU - Holland, J.B. T2 - Genome DA - 2001/// PY - 2001/// DO - 10.1139/gen-44-2-192 VL - 44 IS - 2 SP - 192-204 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035055506&partnerID=MN8TOARS KW - grasses KW - oat KW - genetic mapping KW - homoeology ER - TY - JOUR TI - Thin Soil Layer AU - Miller, G.L. T2 - SportsTurf DA - 2001/11// PY - 2001/11// VL - 17 IS - 11 SP - 42 ER - TY - JOUR TI - Adsorption of barium(II) on montmorillonite: An EXAFS study AU - Zhang, P.-C. AU - Brady, P.V. AU - Arthur, S.E. AU - Zhou, W.-Q. AU - Sawyer, D. AU - Hesterberg, D.A. T2 - Colloids and Surfaces A: Physicochemical and Engineering Aspects AB - Migration of radioactive radium, 226Ra, in soil is an environmental concern, especially in areas adjacent to uranium processing facilities. Barium(II), as Ba2+, was used as a Ra analog and reacted with a Na-montmorillonite to obtain mechanistic insights into the interaction of Ra with soil matrices. The majority of sorbed Ba is associated with the permanently charged surface sites on the montmorillonite basal surface. This is indicated by the facts that (1) sorption of Ba(II) on montmorillonite is not highly sensitive to solution pH, although an increase of sorption was observed at higher pH values; and (2) displacement of sorbed Ba increased with increased NaNO3 concentration. As demonstrated by EXAFS, a small fraction of Ba also adsorbed on the montmorillonite edge, forming an inner-sphere surface complex through sharing of oxygen atom(s) from deprotonated –OH group of the Al octahedral layer. The EXAFS measured distances between Ba and O at the first shell, and Ba and Al of the second shell are 2.7–2.8 and 3.7–3.9 Å, respectively, consistent with the results from geometry of a inner-sphere complex at the edge site. Results from bulk experiments and spectroscopic analysis suggest a co-existence of outer- and inner-sphere surface complexes for Ba sorbed to the montmorillonite surface. DA - 2001/// PY - 2001/// DO - 10.1016/S0927-7757(01)00592-1 VL - 190 IS - 3 SP - 239-249 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035888451&partnerID=MN8TOARS KW - barium KW - sorption KW - EXAFS KW - montmorillonite KW - radium ER - TY - CONF TI - Genome donors of Arachis hypogaea L AU - Tallury, S.P. AU - Milla, S.R. AU - Copeland, S.C. AU - Stalker, H.T. C2 - 2001/// C3 - Proceedings of the American Peanut Research and Education Society DA - 2001/// VL - 33 SP - 60 ER - TY - JOUR TI - Efecto de la profundidad del suelo sobre el establecimiento de plantas de Rottboellia cochinchinensis (Lour.) Clayton en el Agroecosistema de la caña de azúcar (Saccharum officinarum L.) AU - Leon, R. AU - Aguero, R. T2 - Agronomía Mesoamericana AB - Four sugarcane fields with different soil textures (clay loam, sandy loam, clay and loam) were sampled. All fields showed R. cochinchinensis populations with at least 75-150 plants/m2. The number of plants of this weed in 0.25 m2 was determined separately in the microhabitats: rows and between rows. The depth at which each plant emerged was measured. Based on depth emergence, each plant was distributed in one of the next categories: 0, >0-2.5, >2.5-5.0, >5.0-10 and >10.0-15.0 cm. In addition, under greenhouse conditions, seeds were seeded in pots at the maximum depth of each category in order to evaluate the effect of soil depth. Finally, the effect of light and darkness on seed germination were evaluated in Petri dishes under laboratory conditions. In the field evaluations most of the plants emerged from >0-2.5 cm. The second most common category was >2.5-5.0 cm. It seems that those depths provide optimum conditions for germination. There were no differences regarding soil texture or microhabitats. In the greenhouse experiment, the largest germination was observed at 0 cm due to light exposure in this treatment. This was confirmed in the laboratory where light treatment showed also the largest germination. Control strategies that keep the seeds of this species above ground will reduce the number of new seeds in the seed bank and avoid optimum field conditions for its germination. If such strategies include efforts to reduce the seed production of those plants that are able to become established, it could be possible to significantly reduce the seed bank, therefore, it would be easier to control the population of this weed. DA - 2001/// PY - 2001/// DO - 10.15517/am.v12i1.17288 VL - 12 IS - 1 SP - 65-69 ER - TY - JOUR TI - Efecto de distintos tipos de labranza sobre la población de malezas en el Agroecosistema de la caña de azúcar (Saccharum officinarum L.) AU - Leon, R. AU - Aguero, R. T2 - Agronomía Mesoamericana AB - Experiments were conducted in two sugarcane fields, one with low weed pressure (plot 1) and the other with high weed pressure (plot 2). Four treatments were established in each study: green harvest that left plant mulch on soil surface (VCR), green harvest without plant mulch on soil surface (VSR), burning the crop before harvest without soil disturbance (QSL) and burning the crop before harvest with soil disturbance (QCL). Evaluations were made 75 days after harvest. The evaluations were conducted separately in rows and between rows. In addition, sugarcane population and height were measured. Differences in weed populations were not observed for the field with low weed pressure (plot 1). In the field with high weed pressure (plot 2), weeds were favored by burning and soil disturbance caused by fertilizer incorporation. Thus the treatments QSL and QCL showed the highest percentage of surface coverage. Also, the QCL treatment had the greatest weed populations resulting in reduced sugarcane population and height. Purple nutsedge (Cyperus rotundus L.) and itchgrass (Rottboellia cochinchinensis (Lour.) Clayton) had the greatest percentage surface coverage, especially in QCL. Weed populations were larger in rows than between rows. Apparently in rows, weeds found better conditions for germination and nutrient uptake. DA - 2001/// PY - 2001/// DO - 10.15517/am.v12i1.17289 VL - 12 IS - 1 SP - 71-77 ER - TY - CHAP TI - Effective, Safe, and Legal Use of Pesticides AU - Bellinger, B. AU - McLaughlin, R.A. AU - McCarthy, L.B. T2 - Best Golf Course Practices PY - 2001/// PB - Prentice-Hall ER - TY - CHAP TI - Best Golf Course Environmental Protection Strategies AU - Klaine, S.J. AU - McLaughlin, R.A. AU - Bellinger, B. AU - Forsythe, B.L. AU - McCarthy, L.B. AU - Rainwater, T.R. T2 - Best Golf Course Practices PY - 2001/// PB - Prentice-Hall ER - TY - JOUR TI - Surface complexation and dissolution of hematite by C1-C6 dicarboxylic acids at pH = 5.0 AU - Duckworth, O.W. AU - Martin, S.T. T2 - Geochimica et Cosmochimica Acta AB - Adsorption of organic ligands to the surfaces of minerals is a ubiquitous environmental process that often regulates interfacial aqueous chemistry. In the current work, the infrared spectra of dicarboxylate ligands adsorbed to hematite are collected by attenuated total reflectance (ATR) spectroscopy. For each ligand, spectra are recorded at several concentrations at pH = 5.0. Each series of spectra is analyzed by singular value decomposition constrained to a Langmuir adsorption surface model. Oxalate, malonate, and glutarate form bidentate surface complexation structures, whereas succinate and adipate form monodentate structures. The absence of a linear trend in the qualitative form of the binding structure (e.g., bidentate for n = 0, 1, and 3 and monodentate for n = 2 and 4 where n is the length of the carbon chain between carboxylate groups) is attributed to the variation of strain energies for the geometries of possible surface complexation structures. For the bidentate ligands, a linear relationship between the Langmuir binding constant and the second acidity constant is demonstrated. The ligand-promoted dissolution rates at pH = 5.0 are also determined through batch reactor experiments. For the bidentate surface complexes, the dissolution rate at monolayer ligand surface coverage slows in the order oxalate, glutarate, to malonate. Linear relationships are found between the ligand-promoted dissolution rate constants and both the Langmuir binding constants and the second acidity constants. In contrast, succinate and adipate form monodentate surface structures that dissolve slowly, if at all. In this manner, a connection is established between the macroscopic dissolution rate and the microscopic surface complexation structures. DA - 2001/// PY - 2001/// DO - 10.1016/S0016-7037(01)00696-2 VL - 65 IS - 23 SP - 4289-4301 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035664317&partnerID=MN8TOARS ER - TY - JOUR TI - Structure-activity relationships of mineral dusts as heterogeneous nuclei for ammonium sulfate crystallization from supersaturated aqueous solutions AU - Martin, S.T. AU - Schlenker, J. AU - Chelf, J.H. AU - Duckworth, O.W. T2 - Environmental Science and Technology AB - Mineral inclusions, present in aqueous atmospheric salt droplets, regulate crystallization when relative humidity decreases by providing a surface for heterogeneous nucleation and thus reducing the critical supersaturation. Although laboratory studies have quantified these processes to some extent, the diverse atmospheric mineralogy presents more chemical systems than practically feasible for direct study. Structure--activity relationships are necessary. To that end, in the present work the interactions of ammonium sulfate with corundum, hematite, mullite, rutile, anatase, and baddeleyite were studied by diffuse reflectance fourier transform infrared spectroscopy (DRIFTS) and by epitaxial modeling. The spectroscopic results show that shifts in sulfate peak positions due to chemisorption are not a correlative indicator of the efficacy of heterogeneous nucleation. In contrast, epitaxial modeling results of unreconstructed surfaces explain the sequence of critical supersaturations for constant particle size. If validated by further work, this computer modeling method would provide an important structure--activity tool for the estimation of heterogeneous nucleation properties of the atmospheric mineralogy. DA - 2001/// PY - 2001/// DO - 10.1021/es001535v VL - 35 IS - 8 SP - 1624-1629 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035870205&partnerID=MN8TOARS ER - TY - JOUR TI - Water retention of sand-based putting green mixtures as affected by the presence of gravel sub-layers AU - Bigelow, C. A. AU - Bowman, D. C. AU - Cassel, D. K. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 479 ER - TY - JOUR TI - Performance of creeping bentgrass cultivars maintained at two mowing heights and under two fungicide regimes in North Carolina AU - Bruneau, A. H. AU - Bigelow, C. A. AU - Cooper, R. J. AU - Bowman, D. C. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 835 ER - TY - JOUR TI - Conflicts between conservation agriculture and livestock over the utilisation of crop residues AU - Mueller, J. P. AU - Pezo, D. A. AU - Benites, J. AU - Schlaepfer, N. P. T2 - Conservation agriculture, a worldwide challenge : environment, farmers experiences, innovations, socio-economy, policy DA - 2001/// PY - 2001/// DO - 10.1007/978-94-017-1143-2_27 ER - TY - JOUR TI - Yellow nutsedge (Cyperus esculentus L.) as a host of Sclerotinia minor AU - Hollowell, J. E. AU - Shew, B. B. T2 - Plant Disease AB - Sclerotinia minor Jagger is a major pathogen of peanut (Arachis hypogaea L.) in North Carolina, Virginia, Oklahoma, and Texas. Economic crops that are hosts to S. minor are seldom grown in rotation with peanut, and the pathogenicity of S. minor to most weed species commonly found in peanut fields is unknown. In September 2000, signs and symptoms of Sclerotinia infection were observed on plants of yellow nutsedge growing in peanut fields in Bertie County, NC. Fluffy white mycelium, water soaked and bleached areas of the leaves were observed on basal portions of plants. Isolations were made from a symptomatic plant growing in a peanut field at the Peanut Belt Research Station at Lewiston-Woodville, NC. Small portions (1 to 2 cm) of symptomatic leaves were placed on potato dextrose agar (PDA) and pure cultures typical of S. minor were obtained. Small black irregular-shaped sclerotia (<2 mm) were produced abundantly and scattered over the culture surface (1). Pathogenicity was tested by placing agar plugs of mycelium of the fungus between the leaf blades of potted mature yellow nutsedge plants. Plants were misted with water, enclosed in plastic bags, and incubated on a lab counter top at ambient temperature (˜24°C). Mycelia developed after 3 to 4 days and chlorotic leaves appeared by day 7. Sclerotia were observed in 11 days on seedheads, which were distal from the site of inoculation. Uninoculated plants did not develop symptoms. The fungus was reisolated on PDA, and typical cultures of S. minor with small sclerotia were obtained. The nutgrass isolate was inoculated onto detached peanut leaves and typical symptoms developed. This is the first report of yellow nutsedge as a host of S. minor. Reference: (1) L. M. Kohn. Mycotaxon 9:365–444, 1979. DA - 2001/// PY - 2001/// DO - 10.1094/pdis.2001.85.5.562c VL - 85 IS - 5 SP - 562 ER - TY - JOUR TI - Tolerance of perennial ryegrass and Poa annua control with herbicides in overseeded bermudagrass AU - Yelverton, F. H. AU - McCarty, L. B. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 1050 ER - TY - JOUR TI - Temperature effects on nitrogen mineralization in bermudagrass turf AU - Lee, D. J. AU - Wollum, A. G. AU - Bowman, D. C. AU - Peacock, C. H. AU - Rufty, T. W., Jr. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 394 ER - TY - PAT TI - Stable transformation of plant cells AU - Tomes, D. AU - Weissinger, A. AU - Sanford, J. AU - Klein, T. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Response of 'Tifway' bermudagrass (Cynodon dactylon x C. transvaalensis) to N:S:K ratios AU - Peacock, C. H. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 416 ER - TY - JOUR TI - Italian ryegrass control with preplant herbicides AU - Jordan, D. L. AU - Warren, L. S., Jr. AU - Miller, D. K. AU - Smith, M. C. AU - Reynolds, D. B. AU - Crawford, S. H. AU - Griffin, J. L. T2 - Journal of Cotton Science (Online) DA - 2001/// PY - 2001/// VL - 5 IS - 4 SP - 268 ER - TY - JOUR TI - Irrigation requirements for turf establishment under supraoptimal temperature conditions AU - Peacock, C. H. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 SP - 900 ER - TY - JOUR TI - Enhancing disease resistance of crops through breeding and genetics AU - Holland, J. B. T2 - Dealing with genetically modified crops DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Sucrose synthase localizes to cellulose synthesis sites in tracheary elements AU - Salnikov, , VV AU - Grimson, MJ AU - Delmar, DP AU - Haigler, CH T2 - PHYTOCHEMISTRY AB - The synthesis of crystalline cellulose microfibrils in plants is a highly coordinated process that occurs at the interface of the cortex, plasma membrane, and cell wall. There is evidence that cellulose biogenesis is facilitated by the interaction of several proteins, but the details are just beginning to be understood. In particular, sucrose synthase, microtubules, and actin have been proposed to possibly associate with cellulose synthases (microfibril terminal complexes) in the plasma membrane. Differentiating tracheary elements of Zinnia elegans L. were used as a model system to determine the localization of sucrose synthase and actin in relation to the plasma membrane and its underlying microtubules during the deposition of patterned, cellulose-rich secondary walls. Cortical actin occurs with similar density both between and under secondary wall thickenings. In contrast, sucrose synthase is highly enriched near the plasma membrane and the microtubules under the secondary wall thickenings. Both actin and sucrose synthase lie closer to the plasma membrane than the microtubules. These results show that the preferential localization of sucrose synthase at sites of high-rate cellulose synthesis can be generalized beyond cotton fibers, and they establish a spatial context for further work on a multi-protein complex that may facilitate secondary wall cellulose synthesis. DA - 2001/7// PY - 2001/7// DO - 10.1016/S0031-9422(01)00045-0 VL - 57 IS - 6 SP - 823-833 SN - 0031-9422 KW - Zinnia elegans KW - compositae KW - electron microscopic immunolocalization KW - freeze substitution KW - cellulose synthesis KW - sucrose synthase KW - actin KW - microtubule KW - tracheary element KW - secondary cell wall ER - TY - JOUR TI - Sucrose phosphate synthase activity rises in correlation with high-rate cellulose synthesis in three heterotrophic systems AU - Babb, V. M. AU - Haigler, Candace H. T2 - Plant Physiology AB - Based on work with cotton fibers, a particulate form of sucrose (Suc) synthase was proposed to support secondary wall cellulose synthesis by degrading Suc to fructose and UDP-glucose. The model proposed that UDP-glucose was then channeled to cellulose synthase in the plasma membrane, and it implies that Suc availability in cellulose sink cells would affect the rate of cellulose synthesis. Therefore, if cellulose sink cells could synthesize Suc and/or had the capacity to recycle the fructose released by Suc synthase back to Suc, cellulose synthesis might be supported. The capacity of cellulose sink cells to synthesize Suc was tested by analyzing the Suc phosphate synthase (SPS) activity of three heterotrophic systems with cellulose-rich secondary walls. SPS is a primary regulator of the Suc synthesis rate in leaves and some Suc-storing, heterotrophic organs, but its activity has not been previously correlated with cellulose synthesis. Two systems analyzed, cultured mesophyll cells of Zinnia elegans L. var. Envy and etiolated hypocotyls of kidney beans (Phaseolus vulgaris), contained differentiating tracheary elements. Cotton (Gossypium hirsutum L. cv Acala SJ-1) fibers were also analyzed during primary and secondary wall synthesis. SPS activity rose in all three systems during periods of maximum cellulose deposition within secondary walls. The Z. elegans culture system was manipulated to establish a tight linkage between the timing of tracheary element differentiation and rising SPS activity and to show that SPS activity did not depend on the availability of starch for degradation. The significance of these findings in regard to directing metabolic flux toward cellulose will be discussed. DA - 2001/// PY - 2001/// DO - 10.1104/pp.010424 VL - 127 SP - 1234–1242 ER - TY - JOUR TI - Carbon partitioning to cellulose synthesis AU - Haigler, CH AU - Ivanova-Datcheva, M AU - Hogan, PS AU - Salnikov, , VV AU - Hwang, S AU - Martin, K AU - Delmer, DP T2 - PLANT MOLECULAR BIOLOGY DA - 2001/// PY - 2001/// DO - 10.1023/A:1010615027986 VL - 47 IS - 1-2 SP - 29-51 SN - 1573-5028 KW - calcium KW - carbon partitioning KW - cellulose KW - cotton fiber KW - sucrose synthase KW - phosphorylation ER - TY - JOUR TI - Regulation of cellulose biosynthesis in developing xylem AU - Haigler, CH AU - Babb, VM AU - Hwang, S AU - Salnikov, , VV T2 - MOLECULAR BREEDING OF WOODY PLANTS, PROCEEDINGS AB - The advantages of using isolated mesophyll cells of Zinnia elegans as a model to study the regulation of cellulose synthesis will be discussed. These cells can be induced by different mechanisms to expand greatly via primary wall synthesis or to differentiate into tracheary elements with patterned secondary walls. Therefore, mechanisms of cellulose synthesis during primary and secondary wall deposition can be studied separately in cultured cells. Recent work discussed includes the activity and role of sucrose synthase and sucrose phosphate synthase during secondary wall cellulose synthesis and the diversity of cellulose synthase genes expressed during tracheary element differentiation. Evidence obtained during primary and secondary wall synthesis in cultured Zinnia cells is compared and contrasted. Data presented include immunolocalization of sucrose synthase and actin in cryogenically fixed cells, biochemical analysis of sucrose phosphate synthase activity during the time-course of tracheary element differentiation, and cloning and analysis of multiple cellulose synthase genes expressed differentially during secondary wall deposition in tracheary elements in culture. Differentiating cotton fibers and etiolated bean hypocotyls will be discussed as related systems. A composite cellular and metabolic model for cellulose synthesis will be presented. DA - 2001/// PY - 2001/// DO - 10.1016/s0921-0423(01)80050-2 VL - 18 SP - 1-9 SN - 0921-0423 KW - cellulose synthesis KW - cellulose synthase KW - primary wall KW - secondary wall KW - sucrose phosphate synthase KW - sucrose synthase KW - tracheary element KW - Zinnia elegans ER - TY - JOUR TI - Developing and testing a system for studying unsaturated solute transport on undisturbed soil blocks AU - Strock, J. S. AU - Cassel, D. K. T2 - Journal of Soil & Water Conservation DA - 2001/// PY - 2001/// VL - 56 IS - 2 SP - 112-119 ER - TY - JOUR TI - Resistance as a tactic for management of Meloidogyne incognita on cotton in North Carolina AU - Koenning, S. R. AU - Barker, K. R. AU - Bowman, D. T. T2 - Journal of Nematology DA - 2001/// PY - 2001/// VL - 33 IS - 2-3 SP - 126-131 ER - TY - JOUR TI - Polymorphism of PCR-based markers targeting exons, introns, promoter regions, and SSRs in maize and introns and repeat sequences in oat AU - Holland, JB AU - Helland, SJ AU - Sharopova, N AU - Rhyne, DC T2 - GENOME DA - 2001/12// PY - 2001/12// DO - 10.1139/gen-44-6-1065 VL - 44 IS - 6 SP - 1065-1076 SN - 1480-3321 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035543144&partnerID=MN8TOARS KW - Avena KW - Zea KW - genetic diversity KW - DNA sequence ER - TY - JOUR TI - Comparison of fatty acid content of milk from jersey and Holstein cows consuming pasture or a total mixed ration AU - White, SL AU - Bertrand, JA AU - Wade, MR AU - Washburn, SP AU - Green, JT AU - Jenkins, TC T2 - JOURNAL OF DAIRY SCIENCE AB - Holstein (n = 19) and Jersey (n = 18) cows were used to study effects of two feeding systems on fatty acid composition of milk. Confinement cows were fed a total mixed ration with corn silage and alfalfa silage and pastured cows grazed a crabgrass (90%) and clover (10%) pasture and were allowed 5.5 kg of grain per head daily. Two milk samples were collected from each cow at morning and afternoon milkings 1 d each week for four consecutive weeks in June and July 1998. One set of milk samples was analyzed to determine fatty acid composition, and the second set was used for crude protein and total fat analyses. Data were analyzed by the general linear models procedure of SAS, using a split-plot model with breed, treatment, and breed x treatment as main effects and time of sampling and week as subplot effects along with appropriate interactions. Milk from pastured cows was higher than milk from confinement cows for the cis-9, trans-11 octadecadienoic acid isomer of conjugated linoleic acid (CLA). Also, milk from Holsteins was higher than milk from Jerseys for C16:1, C18:1, and CLA and lower than Jerseys for C6:0, C8:0, C10:0, C12:0, and C14:0. Several treatment x week interactions existed, but main effects were still important; for example, proportions of CLA in milk of grazed cows were relatively constant across weeks (0.66, 0.64, 0.64, and 0.69% +/- 0.02%, respectively), but the CLA in milk of confinement cows increased in wk 4 (0.35, 0.31, 0.31, and 0.48% +/- 0.02% for wk 1 to 4, respectively). There are potentially important differences in fatty acid composition of milk from cows consuming a warm season pasture species compared with milk from cows consuming a total mixed ration, as well as differences between Holstein and Jersey breeds. DA - 2001/10// PY - 2001/10// DO - 10.3168/jds.S0022-0302(01)74676-0 VL - 84 IS - 10 SP - 2295-2301 SN - 0022-0302 KW - conjugated linoleic acid KW - pasture KW - fatty acids ER - TY - JOUR TI - Mail order, the Internet, and invasive aquatic weeds AU - Kay, S. H. AU - Hoyle, S. T. T2 - Journal of Aquatic Plant Management DA - 2001/// PY - 2001/// VL - 39 IS - 2001 Jan SP - 88-91 ER - TY - JOUR TI - Weed management with pyrithiobac preemergence in bromoxynil-resistant cotton AU - Paulsgrove, MD AU - Wilcut, JW T2 - WEED SCIENCE AB - An experiment was conducted at two locations in Georgia and one location in North Carolina during 1994 and 1995 to evaluate weed management systems utilizing pyrithiobac applied preemergence (PRE) in conventional-tillage bromoxynil-resistant cotton. Weed management systems evaluated included different combinations of pyrithiobac PRE, bromoxynil or bromoxynil plus MSMA applied early postemergence (EPOST), bromoxynil applied postemergence (POST), and cyanazine plus MSMA applied late postemergence-directed (LAYBY). Pyrithiobac PRE improved control of Florida beggarweed, pitted morningglory, prickly sida, sicklepod, and spurred anoda compared with systems that did not include pyrithiobac PRE. Averaged across locations, pyrithiobac PRE increased cotton lint yields 330 kg ha−1. Bromoxynil applied EPOST or POST increased weed control and cotton lint yield. Bromoxynil EPOST, POST, or EPOST plus POST did not control sicklepod. The addition of MSMA to bromoxynil EPOST improved sicklepod control. Two applications of bromoxynil controlled more pitted morningglory and sicklepod than one application. Control of all dicotyledonous weeds was increased by cyanazine plus MSMA LAYBY, and this treatment increased yields at all locations. Cotton was not injured by pyrithiobac PRE or by bromoxynil applied EPOST or POST, but temporary visual injury was observed with EPOST treatments of MSMA. DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0567:WMWPPI]2.0.CO;2 VL - 49 IS - 4 SP - 567-570 SN - 0043-1745 KW - bromoxynil KW - cyanazine KW - fluometuron KW - MSMA KW - pyrithiobac KW - cotton, Gossypium hirsutum L. 'BXN 57' KW - Florida beggarweed, Desmodium tortuosum (Sw.) DC. DEDTO KW - pitted morningglory, Ipomoea lacunosa L. IPOLA KW - prickly sida, Sida spinosa L. SIDSP KW - sicklepod, Senna obtusifolia (L.) Irwin and Barneby CASOB KW - spurred anoda, Anoda cristata (L.) Schlecht. ANVCR KW - cotton yield KW - herbicide-resistant crops ER - TY - JOUR TI - Virginia market-type peanut (Arachis hypogaea) cultivar tolerance and yield response to flumioxazin preemergence AU - Wilcut, JW AU - Askew, SD AU - Bailey, WA AU - Spears, JF AU - Isleib, TG T2 - WEED TECHNOLOGY AB - Field studies were conducted in 1996 and 1997 to evaluate response of eight peanut cultivars to flumioxazin applied preemergence (PRE) at 71 g ai/ha. Peanut cultivars evaluated include ‘NC 12C’, ‘NC 7’, ‘VAC 92R’, ‘NC-V 11’, ‘NC 10C’, ‘AT VC 1’, ‘NC 9’, and the experimental breeding line ‘N9001OE’. Visible injury 3 wk after planting in 1996 was 3% or less regardless of cultivar. In 1997, all cultivars were injured 15 to 28% with flumioxazin PRE, except VC 1, which was injured 45%. No visible injury was observed at 5 and 9 wk after planting. Flumioxazin did not influence the incidence of early leaf spot, late leaf spot, southern stem rot, cylindrocladium black rot, or tomato spotted wilt virus. Flumioxazin did not affect percentage of extra-large kernels, sound mature kernels, other kernels, and total yield.Nomenclature: Flumioxazin; peanut, Arachis hypogaea L., ‘NC 12C’, ‘NC 7’, ‘VAC 92R’, ‘NC-V 11’, ‘NC 10C’, ‘AT VC 1’, ‘NC 9’, ‘N9001OE’.Additional index words: Disease interaction, Cylindrocladium crotalariae (Loos) Bell and Sobers, Cercospora arachidicola Hori, Cercosporidium personatum (Berk. and Curt.), Sclerotium rolfsii Sacc., grade parameters, extra-large kernels, sound mature kernels, sound splits, total kernels, other kernels, fancy pods.Abbreviations: CBR, cylindrocladium black rot; DAP, days after planting; ELK, extra-large kernels; PPI, preplant incorporated; PRE, preemergence; SMK, sound mature kernels; SS, sound splits; TMSK, total sound mature kernels; TSWV, tomato spotted wilt virus; WAP, weeks after planting. DA - 2001/// PY - 2001/// DO - 10.1614/0890-037X(2001)015[0137:VMTPAH]2.0.CO;2 VL - 15 IS - 1 SP - 137-140 SN - 1550-2740 KW - disease interaction KW - Cylindrocladium crotalariae (Loos) Bell and Sobers KW - Cercospora arachidicola Hori KW - Cercosporidium personatum (Berk. and Curt.) KW - Sclerotium rolfsii Sacc. KW - grade parameters KW - extra-large kernels KW - sound mature kernels KW - sound splits KW - total kernels KW - other kernels KW - fancy pods ER - TY - JOUR TI - Tropic croton interference in cotton AU - Askew, SD AU - Wilcut, JW T2 - WEED SCIENCE AB - Studies were conducted to determine the effect of interference between tropic croton (Croton glandulosus) and cotton (Gossypium hirsutum) on plant growth and productivity. Tropic croton height was not affected by weed density, but cotton height decreased with increased weed density 10 wk after planting. Tropic croton biomass per plant was not affected by weed density, but total weed biomass per meter of crop row increased with weed density. Cotton lint yield decreased linearly 2 kg ha−1 with each gram increase in weed dry biomass per meter of row. Percent yield loss–density relationship was described by the rectangular hyperbola model. Estimated coefficients A (maximum yield loss) and I (yield loss per unit density as density approaches zero) were 129.6 ± 42.2 and 35.6 ± 8.0%, respectively, when asymptotic iterations were based on least sums of squares. When A was constrained to 100% yield loss, I was 42.5 ± 5.1%. Results indicated that tropic croton was less competitive with cotton than many weeds but represents an economic threat to cotton growers. DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0184:TCIIC]2.0.CO;2 VL - 49 IS - 2 SP - 184-189 SN - 1550-2759 KW - cotton, Gossypium hirsutum L. 'Deltapine 5 1' KW - tropic croton, Croton glandulosus var. septentrionalis Muell.-Arg. CVNGS KW - competition KW - crop height KW - economic thresholds KW - models KW - weed biomass KW - weed density KW - weed height ER - TY - JOUR TI - Sea grant and invasive aquatic plants: A national outreach initiative AU - Crawford, H. M. AU - Jensen, D. A. AU - Peichel, B. AU - Charlebois, P. M. AU - Doll, B. A. AU - Kay, S. H. AU - Ramey, V. A. AU - O'Leary, M. B. T2 - Journal of Aquatic Plant Management DA - 2001/// PY - 2001/// VL - 39 IS - 2001 Jan SP - 8-11 ER - TY - JOUR TI - Morningglory (Ipomoea spp.) and large crabgrass (Digitaria sanguinalis) control with glyphosate and 2,4-DB mixtures in glyphosate-resistant soybean (Glycine max) AU - Culpepper, AS AU - Gimenez, AE AU - York, AC AU - Batts, RB AU - Wilcut, JW T2 - WEED TECHNOLOGY AB - Glyphosate effectively controls most weeds in glyphosate-resistant soybean. However, it is sometimes only marginally effective on Ipomoea spp. A field experiment was conducted at five locations in North Carolina to determine the effects of mixing 2,4-DB with glyphosate on Ipomoea spp. control and on soybean injury and yield. The isopropylamine salt of glyphosate at 560, 840, and 1,120 g ai/ha controlled mixtures of tall morningglory, entireleaf morningglory, and red morningglory at least 96% at two locations. Mixing the dimethylamine salt of 2,4-DB at 35 g ae/ha with glyphosate did not increase control but reduced soybean yield 6%. At two other locations, 2,4-DB increased control of tall morningglory and a mixture of entireleaf morningglory and ivyleaf morningglory 13 to 22% when mixed with glyphosate at 560 g/ha, but not when mixed with glyphosate at 840 or 1,120 g/ha. Soybean yield was reduced 31% at one location and was unaffected at the other. At the fifth location, 2,4-DB increased control of tall morningglory 25, 11, and 7% when mixed with glyphosate at 560, 840, and 1,120 g/ha, respectively. Soybean yield was increased 15%. In separate field experiments, glyphosate at 560, 840, and 1,120 g/ha controlled large crabgrass at least 99%. Mixing 2,4-DB at 35 g/ha with glyphosate did not affect control. In the greenhouse, mixing 2,4-DB at 35, 70, 140, or 280 g/ha with glyphosate at 70 to 560 g/ha did not affect large crabgrass control by glyphosate.Nomenclature: Glyphosate; 2,4-DB; entireleaf morningglory, Ipomoea hederacea var. integriuscula Gray #3 IPOHG; ivyleaf morningglory, Ipomoea hederacea (L.) Jacq. # IPOHE; large crabgrass, Digitaria sanguinalis (L.) Scop. # DIGSA; red morningglory, Ipomoea coccinea L. # IPOCC; tall morningglory, Ipomoea purpurea (L.) Roth # PHBPU; soybean, Glycine max (L.) Merr. ‘Hartz 5566 RR’.Additional index words: Herbicide combinations, herbicide interactions, herbicide-resistant crops.Abbreviations: WAT, weeks after treatment. DA - 2001/// PY - 2001/// DO - 10.1614/0890-037X(2001)015[0056:MISALC]2.0.CO;2 VL - 15 IS - 1 SP - 56-61 SN - 0890-037X KW - herbicide combinations KW - herbicide interactions KW - herbicide-resistant crops ER - TY - JOUR TI - Influence of norflurazon placement on yellow nutsedge (Cyperus esculentus) AU - McLean, HS AU - Richburg, JS AU - Wilcut, JW AU - Smith, AE T2 - WEED TECHNOLOGY AB - Greenhouse studies were conducted to determine yellow nutsedge response to selective placement of a 5-cm layer of norflurazon-treated soil above, below, or above plus below pregerminated nutsedge tubers. Norflurazon at 1.68 kg ai/ha applied postemergence (POST) as a foliar, soil, or foliar plus soil treatment was also evaluated. Soil concentrations of norflurazon at 1.5 mg/kg (w/w) applied below or above plus below nutsedge tubers reduced yellow nutsedge shoot numbers at least 69%, shoot height at least 71%, shoot dry weights at least 77%, and root tuber dry weights at least 89%. Yellow nutsedge growth reduction with norflurazon was greatest when norflurazon was placed in the soil profile below or above plus below the yellow nutsedge tubers. Placement of norflurazon above yellow nutsedge tubers did not reduce shoot number, height, or dry weight until the foliar portion of plants were removed 39 d after treatment. POST application of norflurazon did not reduce initial yellow nutsedge shoot number regardless of application method. Foliar-only POST application of norflurazon was less effective for reducing numbers of emerged yellow nutsedge than application to soil only or soil plus foliage.Nomenclature: Norflurazon; yellow nutsedge, Cyperus esculentus L. #3 CYPES.Additional index words: Application method, herbicide placement, timing, herbicide concentration, cotton, Gossypium hirsutum.Abbreviations: DAT, days after treatment; POST, postemergence. DA - 2001/// PY - 2001/// DO - 10.1614/0890-037X(2001)015[0327:IONPOY]2.0.CO;2 VL - 15 IS - 2 SP - 327-331 SN - 1550-2740 KW - application method KW - herbicide placement KW - timing KW - herbicide concentration KW - cotton KW - Gossypium hirsutum ER - TY - JOUR TI - Formation of parthenocarpic fruit, undeveloped flowers and aborted flowers in tomato under moderately elevated temperatures AU - Sato, S AU - Peet, MM AU - Gardner, RG T2 - SCIENTIA HORTICULTURAE AB - Incidence of parthenocarpic fruit, undeveloped flowers and flower abortion in tomato plants (Lycopersicon esculentum Mill.) were compared under optimal temperature (OT, 28/22°C day/night) and chronic, mild high temperature conditions (HT, 32/26°C). Seeded fruits were found only under OT conditions, where 37±9% of all flowers developed into seeded fruit. However, flower aborted was also higher under OT, with an additional 24±7% of flowers aborted under optimal temperature conditions, compared to only 4±1% of flowers aborted under HT conditions. Under HT, most flowers (53±8%) developed into parthenocarpic fruit, and the remainder (43±7%) stayed on the plant as undeveloped flowers. A slow transition of undeveloped flowers to parthenocarpic fruit was also observed under HT. Factors determining whether flowers abort, develop parthenocarpically, remain on the plant without developing further, or develop into seeded fruit were discussed in relation to carbohydrate availability and the presence of seeded fruit on the vine. DA - 2001/11/16/ PY - 2001/11/16/ DO - 10.1016/S0304-4238(00)00262-4 VL - 90 IS - 3-4 SP - 243-254 SN - 0304-4238 KW - Lycopersicon esculentum. Mill. KW - moderately elevated temperatures KW - heat stress KW - flower development KW - parthenocarpy KW - flower abortion KW - seedlessness ER - TY - JOUR TI - Effect of insecticides on clomazone absorption, translocation, and metabolism in cotton AU - Culpepper, AS AU - York, AC AU - Marth, JL AU - Corbin, FT T2 - WEED SCIENCE AB - Disulfoton and phorate applied in the seed furrow greatly reduce clomazone phytotoxicity to cotton in the field, whereas aldicarb does not. An experiment was conducted to determine the effect of aldicarb, disulfoton, and phorate on 14C-clomazone absorption, translocation, and metabolism by cotton grown in a sandy loam soil. Clomazone at 0.87 μg g−1 of soil alone or in combination with aldicarb at 0.6 μg g−1 of soil reduced cotton root and shoot growth 26 to 33%. Root and shoot growth were not reduced by clomazone plus disulfoton or phorate at 0.6 μg g−1 of soil. Protection of cotton against injury by clomazone was not explained by reduced absorption or translocation of clomazone or a metabolite to the shoot. Clomazone metabolism was reduced by disulfoton and phorate, thus indicating a clomazone metabolite may be more toxic to cotton. DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0613:EOIOCA]2.0.CO;2 VL - 49 IS - 5 SP - 613-616 SN - 0043-1745 KW - aldicarb KW - clomazone KW - disulfoton KW - phorate KW - cotton, Gossypium hirsutum L. 'McNair 235' KW - carbamate insecticides KW - herbicide-insecticide interactions KW - organophosphate insecticides ER - TY - JOUR TI - Economic evaluation of diclosulam and flumioxazin systems in peanut (Arachis hypogaea) AU - Scott, GH AU - Askew, SD AU - Wilcut, JW T2 - WEED TECHNOLOGY AB - Field studies were conducted at two locations in North Carolina in 1998 and in 1999 to evaluate weed control and peanut response following diclosulam at 27 g ai/ha preemergence (PRE) or flumioxazin at 87 g ai/ha preemergence (PRE) alone and in systems with postemergence (POST) commercial standards. All plots received a preplant incorporated (PPI) treatment of metolachlor at 1,400 g ai/ha. Metolachlor PPI plus diclosulam or flumioxazin PRE controlled common lambsquarters, common ragweed, entireleaf morningglory, large crabgrass, and yellow nutsedge as well as or better than metolachlor PPI followed by (fb) acifluorfen plus bentazon POST or paraquat plus bentazon early postemergence fb acifluorfen plus bentazon POST. Metolachlor PPI plus diclosulam PRE or flumioxazin PRE controlled ivyleaf morningglory as well as metolachlor PPI fb acifluorfen plus bentazon POST. Metolachlor PPI plus flumioxazin PRE controlled common lambsquarters better than metolachlor PPI plus diclosulam PRE while diclosulam PRE controlled common ragweed better. There was no difference in common lambsquarters control between flumioxazin and diclosulam PRE when POST herbicides were used. There was only one difference in peanut yield and net returns between metolachlor PPI fb either diclosulam or flumioxazin PRE when POST herbicides were used.Nomenclature: Acifluorfen; bentazon; diclosulam; flumioxazin; metolachlor; paraquat; common lambsquarters, Chenopodium album L. #3 CHEAL; common ragweed, Ambrosia artemisiifolia L. # AMBEL; entireleaf morningglory, Ipomoea hederacea var. integriuscula Gray # IPOHG; ivyleaf morningglory, Ipomoea hederacea (L.) Jacq. # IPOHE; large crabgrass, Digitaria sanguinalis L. Scop. # DIGSA; yellow nutsedge, Cyperus esculentus L. # CYPES; peanut, Arachis hypogaea L., ‘NC 7’, ‘NC 10C’.Additional index words: Economic analysis, acifluorfen, bentazon, paraquat.Abbreviations: EPOST, early postemergence; fb, followed by; POST, postemergence; PPI, preplant incorporated; PRE, preemergence. DA - 2001/// PY - 2001/// DO - 10.1614/0890-037X(2001)015[0360:EEODAF]2.0.CO;2 VL - 15 IS - 2 SP - 360-364 SN - 0890-037X KW - economic analysis KW - acifluorfen KW - bentazon KW - paraquat ER - TY - JOUR TI - Economic evaluation of HADSS (TM) computer program for weed management in nontransgenic and transgenic cotton AU - Scott, GH AU - Askew, SD AU - Bennett, AC AU - Wilcut, JW T2 - WEED SCIENCE AB - Field studies were conducted at four locations in North Carolina in 1998 and 1999 to evaluate the use of the Herbicide Application Decision Support System (HADSS™) for weed management in nontransgenic, bromoxynil-resistant, and glyphosate-resistant cotton. Weed management systems included trifluralin preplant incorporated (PPI) plus fluometuron preemergence (PRE) or no soil-applied herbicides. Postemergence (POST) options included bromoxynil, glyphosate, or pyrithiobac early POST (EPOST) followed by (fb) MSMA plus prometryn late postemergence–directed (LAYBY) or herbicide recommendations given by HADSS. Glyphosate-resistant systems provided control equivalent to or better than control provided by bromoxynil-resistant and nontransgenic systems for smooth pigweed, Palmer amaranth, large crabgrass, goosegrass, ivyleaf morningglory, and fall panicum. Trifluralin PPI fb fluometuron PRE fb HADSS POST provided equivalent or higher levels of weed control and yield than trifluralin PPI fb fluometuron PRE fb bromoxynil, glyphosate, or pyrithiobac EPOST fb MSMA plus prometryn LAYBY. The trifluralin PPI fb fluometuron PRE fb HADSS POST systems controlled large crabgrass at Goldsboro and fall panicum better than HADSS POST-only systems in nontransgenic cotton. Cotton yield and net returns in the glyphosate-resistant systems were always equal to or higher than the nontransgenic and bromoxynil-resistant systems. Net returns were higher for the soil-applied fb HADSS POST treatments in 8 of 12 comparisons with HADSS POST systems without soil-applied herbicides. Early-season weed interference reduced cotton lint yields and net returns in POST-only systems. DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0549:EEOHCP]2.0.CO;2 VL - 49 IS - 4 SP - 549-557 SN - 1550-2759 KW - bromoxynil KW - fluometuron KW - glyphosate KW - MSMA KW - prometryn KW - pyrithiobac KW - trifluralin KW - cotton, Gossypium hirsutum L. 'Deltapine 51' KW - 'BXN 47', 'Delrapine 5415RR' KW - fall panicum, Panicum dichotomiflorum Michx. PANDI KW - goosegrass, Eleusine indica (L.) Gaertn. ELEIN KW - ivyleaf morningglory, Ipomoea hederacea (L.) KW - Jacq. IPOHE KW - large crabgrass KW - Digitaria sanguinalis (L.) scop. DIGSA KW - Palmer amaranth, Amaranthus palmeri S. Wats. AMAPA KW - smooth pigweed, Amaranthus hybridus L. KW - AMACH KW - computer decision aids KW - HERB KW - herbicide-resistant crops ER - TY - JOUR TI - Correlated responses of fatty acid composition, grain quality, and agronomic traits to nine cycles of recurrent selection for increased oil content in oat AU - Holland, JB AU - Frey, KJ AU - Hammond, EG T2 - EUPHYTICA DA - 2001/// PY - 2001/// DO - 10.1023/A:1012639821332 VL - 122 IS - 1 SP - 69-79 SN - 1573-5060 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0043198664&partnerID=MN8TOARS KW - Avena KW - fatty acid composition KW - genetic correlation KW - groat-oil KW - recurrent selection ER - TY - JOUR TI - Absorption and translocation of glyphosate in glyphosate-resistant cotton as influenced by application method and growth stage AU - Pline, WA AU - Price, AJ AU - Wilcut, JW AU - Edmisten, KL AU - Wells, R T2 - WEED SCIENCE AB - The influence of herbicide placement and plant growth stage on the absorption and translocation patterns of 14C-glyphosate in glyphosate-resistant cotton was investigated. Plants at four growth stages were treated with 14C-glyphosate on a 5-cm2 section of the stem, which simulated a postemergence-directed spray (PDS) application, or on the newest mature leaf, which simulated a postemergence (POST) application. Plants were harvested 3 and 7 d after treatment and divided into the treated leaf or treated stem, mature leaves, immature leaves and buds, stems, roots, fruiting branches (including the foliage on the fruiting branch), squares, and bolls. The PDS versus POST application main effect on absorption was significant. Absorption of 14C-glyphosate applied to stem tissue was higher in PDS applications than in POST applications. Plants receiving PDS applications absorbed 35% of applied 14C-glyphosate, whereas those receiving POST applications absorbed 26%, averaged over growth stages at application. Absorption increased from the four-leaf growth stage to the eight-leaf stage in POST applications but reached a plateau at the eight-leaf stage. Plants with PDS applications showed an increase in absorption from the four- to eight- to twelve-leaf stages and reached a plateau at the 12-leaf stage. Translocation of 14C-glyphosate to roots was greater at all growth stages with PDS treatments than with POST treatments. Herbicide placement did not affect translocation of 14C-glyphosate to squares and bolls. Squares and bolls retained 0.2 to 3.7% of applied 14C-glyphosate, depending on growth stage. Separate studies were conducted to investigate the fate of foliar-applied 14C-glyphosate at the four- or eight-leaf growth stages when harvested at 8- or 10-leaf, 12-leaf, midbloom (8 to 10 nodes above white bloom), and cutout (five nodes above white bloom, physiological maturity) stages. Thirty to 37% of applied 14C-glyphosate remained in the plant at cutout in four- and eight-leaf treatment stages, respectively. The concentration of 14C-glyphosate in tissue (Bq g−1 dry weight basis) was greatest in mature leaves and immature leaves and buds in plants treated at the four-leaf stage. Plants treated at the eight-leaf stage and harvested at all growth stages except cutout showed a higher concentration of 14C-glyphosate in squares than in other plant tissue. Accumulation of 14C-glyphosate in squares reached a maximum of 43 Bq g−1 dry weight at harvest at the 12-leaf stage. This concentration corresponds to 5.7 times greater accumulation of 14C-glyphosate in squares than in roots, which may also be metabolic sinks. These data suggest that reproductive tissues such as bolls and squares can accumulate 14C-glyphosate at higher concentrations than other tissues, especially when the herbicide treatment is applied either POST or PDS during reproductive stages (eight-leaf stage and beyond). DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0460:AATOGI]2.0.CO;2 VL - 49 IS - 4 SP - 460-467 SN - 0043-1745 KW - glyphosate KW - cotton, Gossypium hirsutum L. 'Delta pine 5415RR' KW - herbicide-resistant crops KW - transgenic crops ER - TY - JOUR TI - Using yield monitor data to determine spatial crop production potential AU - Taylor, R. K. AU - Kluitenberg, G. J. AU - Schrock, A. D. AU - Zhang, N. AU - Schmidt, J. P. AU - Havlin, J. L. T2 - Transactions of the ASAE AB - Consistent spatialtemporal yield patterns should help determine spatial production potential. Our objective wasto evaluate methods for using yield monitor data to develop spatial yield goal maps. Three to seven years of yield monitordata were analyzed for five sprinklerirrigated cornfields in central and western Kansas. Yield data were blockaveragedto 55 m square cells, normalized based on the mean yield, and then used to develop spatial yield goals for subsequent yearsusing six different methods. One method used a uniform yield goal, two methods combined normalized yield monitor data witha uniform yield goal (transitional), and three methods used only normalized yield monitor data from previous years. Methodswere evaluated based on their ability to predict the spatial yield pattern of the subsequent year better than the uniform method.Yield monitor data were also segregated based on the temporal CV of each field during the time of the study, and the sixmethods were evaluated only on the data that were deemed temporally stable.

The result of incorporating yield monitor data into yield goals was inconsistent across sites and years. For one site, thetwo transitional and three yield monitor methods were significantly better predictors of normalized yield. On another field,the uniform method was a better predictor of normalized yield than the yield monitor methods in three of six years, while theyield monitor methods were better than the uniform method in another year. On a third field, the yield monitor methodpredicted normalized yield better than the uniform method in one of four years with no difference in the other three years.In general, when the correlation coefficient between two years of yield monitor data exceeded 0.70, the methods thatincorporated yield monitor data into the yield goal were better predictors of normalized yield than the uniform method.Evaluating these methods using only data from cells where the temporal CV was less than the average temporal CV for thefield did not improve the results sufficiently to warrant widespread use of this practice. DA - 2001/// PY - 2001/// DO - 10.13031/2013.7007 VL - 44 IS - 6 SP - 1409-1414 ER - TY - JOUR TI - Registration of NC 72 cotton germplasm line AU - Bowman, DT T2 - CROP SCIENCE AB - Crop ScienceVolume 41, Issue 4 p. 1369-1369 Registration of Germplasm Registration of NC 72 Cotton Germplasm Line Daryl T. Bowman, Corresponding Author Daryl T. Bowman daryl_bowman@ncsu.edu Crop Science Dep., Box 8604, North Carolina State Univ., Raleigh, NC, 27695-8604Corresponding author (daryl_bowman@ncsu.edu)Search for more papers by this author Daryl T. Bowman, Corresponding Author Daryl T. Bowman daryl_bowman@ncsu.edu Crop Science Dep., Box 8604, North Carolina State Univ., Raleigh, NC, 27695-8604Corresponding author (daryl_bowman@ncsu.edu)Search for more papers by this author First published: 01 July 2001 https://doi.org/10.2135/cropsci2001.4141369xCitations: 2 Research supported in part by Cotton Inc. Registration by CSSA. 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 Citing Literature Volume41, Issue4July 2001Pages 1369-1369 RelatedInformation DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4141369x VL - 41 IS - 4 SP - 1369-1369 SN - 0011-183X ER - TY - JOUR TI - Oxidation of phytosterols in a test food system AU - Oehrl, LL AU - Hansen, AP AU - Rohrer, CA AU - Fenner, GP AU - Boyd, LC T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract The oxidative stability of phytosterols in canola, coconut, peanut, and soybean oils was examined under simulated frying conditions of 100, 150, and 180°C for 20 h. The degree of oxidative decomposition was assessed by the loss of phytosterols, accumulation of phytosterol oxides, and the change in fatty acid profiles. The phytosterol oxides produced in the oils were identified using mass spectroscopy. Oils with higher levels of polyunsaturated fatty acids showed greater amounts of sterol loss; however, the sterol loss was less complete than in the more saturated oils. A greater variety of sterol oxides was observed at the lower temperatures of 100 and 150°C compared to 180°C. This study demonstrates that under conditions similar to frying, there is a loss of phytosterols and polyunsaturated fatty acids. The accumulation of phytosterol oxides may be temperature‐limited because of further break‐down into products not measurable by typical gas chromatography‐mass spectrometry techniques. DA - 2001/11// PY - 2001/11// DO - 10.1007/s11746-001-0391-z VL - 78 IS - 11 SP - 1073-1078 SN - 0003-021X KW - canola oil KW - coconut oil KW - frying vegetable oils KW - heating effects KW - peanut oil KW - phytosterol oxides KW - soybean oil ER - TY - JOUR TI - Molecular determinants influencing the inheritance of transgenic virus resistance in segregating tobacco families transformed with the nucleocapsid gene of tomato spotted wilt virus AU - Herrero, S AU - Rufty, RC AU - Daub, ME T2 - MOLECULAR BREEDING DA - 2001/// PY - 2001/// DO - 10.1023/A:1011381412397 VL - 7 IS - 2 SP - 131-139 SN - 1572-9788 KW - breeding KW - disease resistance KW - tomato spotted wilt virus KW - tobacco KW - transgenic ER - TY - JOUR TI - Molecular cloning and expression of eight laccase cDNAs in loblolly pine (Pinus taeda) AU - Sato, Y AU - Bao, WL AU - Sederoff, R AU - Whetten, R T2 - JOURNAL OF PLANT RESEARCH DA - 2001/6// PY - 2001/6// DO - 10.1007/PL00013978 VL - 114 IS - 1114 SP - 147-155 SN - 1618-0860 KW - laccase KW - lignin synthesis KW - loblolly pine (Pinus taeda L) KW - xylem differentiation ER - TY - JOUR TI - Impact of light-weight rolling on putting green performance AU - Hartwiger, CE AU - Peacock, CH AU - DiPaola, JM AU - Cassel, DK T2 - CROP SCIENCE AB - The introduction of light‐weight rollers has contributed to the reconsideration of the practice of rolling golf putting greens. Studies were conducted in 1993 and 1994 to determine the effects of rolling on soil bulk density, putting green speed, turf quality, root mass, and thatch mass. Experimental ‘Penncross’ creeping bentgrass ( Agrostis stolonifera L.) putting greens built on a United States Golf Association (USGA) specification root zone and on a Cecil gravelly sandy loam (Typic Hapludult clayey, kaolinitic, thermic) (native soil) root zone were mowed daily and subjected to four rates of rolling (0, 1, 4, or 7 times per week) with a light‐weight roller for a 10‐wk period. Soil bulk density did not change for any rolling frequency on the USGA green. Rolling rates of four and seven times per week increased bulk density on the native soil green by 4 and 3% in the first year while no changes were detected in the second year. Turf quality was diminished for rolling rates of four and seven times per week. Ball roll increased as the rate of rolling increased. Rolling rate did not alter root mass. Thatch levels were not affected by rolling frequency on the USGA green. On the native soil green, four and seven rolling treatments per week resulted in thatch levels 12 and 11% higher than the control. Rolling once per week appears to offer increased green speed without any deleterious turf effects. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4141179x VL - 41 IS - 4 SP - 1179-1184 SN - 0011-183X ER - TY - JOUR TI - Genetic relationships of crown rust resistance, grain yield, test weight, and seed weight in oat AU - Holland, JB AU - Munkvold, GP T2 - CROP SCIENCE AB - Integrating selection for agronomic performance and quantitative resistance to crown rust, caused by Puccinia coronata Corda var. avenae W.P. Fraser & Ledingham, in oat ( Avena sativa L.) requires an understanding of their genetic relationships. This study was conducted to investigate the genetic relationships of crown rust resistance, grain yield, test weight, and seed weight under both inoculated and fungicide‐treated conditions. A Design II mating was performed between 10 oat lines with putative partial resistance to crown rust and nine lines with superior grain yield and grain quality potential. Progenies from this mating were evaluated in both crown rust‐inoculated and fungicide‐treated plots in four Iowa environments to estimate genetic effects and phenotypic correlations between crown rust resistance and grain yield, seed weight, and test weight under either infection or fungicide‐treated conditions. Lines from a random‐mated population derived from the same parents were evaluated in three Iowa environments to estimate heritabilities of, and genetic correlations between, these traits. Resistance to crown rust, as measured by area under the disease progress curve (AUDPC), was highly heritable ( H = 0.89 on an entry‐mean basis), and was favorably correlated with grain yield, seed weight, and test weight measured in crown rust‐inoculated plots. AUDPC was unfavorably correlated or uncorrelated with grain yield, test weight, and seed weight measured in fungicide‐treated plots. To improve simultaneously crown rust resistance, grain yield, and seed weight under both lower and higher levels of crown rust infection, an optimum selection index can be developed with the genetic parameters estimated in this study. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4141041x VL - 41 IS - 4 SP - 1041-1050 SN - 0011-183X UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034891094&partnerID=MN8TOARS ER - TY - JOUR TI - Developing agronomic high-protein soybeans AU - Wilson, R. F. T2 - Agrofoodindustry Hi-tech DA - 2001/// PY - 2001/// VL - 12 IS - 5 SP - 17-22 ER - TY - JOUR TI - Reproductive allocation on branches of Virginia-type peanut cultivars bred for yield in North Carolina AU - Anis-Ur-Rehman, W. R. AU - Isleib, T. G. T2 - Crop Science DA - 2001/// PY - 2001/// VL - 41 IS - 1 SP - 72-77 ER - TY - JOUR TI - Remote sensing of winter wheat tiller density for early nitrogen application decisions AU - Flowers, M AU - Weisz, R AU - Heiniger, R T2 - AGRONOMY JOURNAL AB - There is increasing evidence that scouting of winter wheat ( Triticum aestivum L.) fields to determine tiller density at Growth Stage (GS) 25 is useful in deciding if N should be applied. However, to obtain an accurate average of field tiller density, frequent and intensive measurements must be made. A solution to this problem may be remote sensing. The objectives of this study were to determine (i) if a spectral index or digital counts in the near infrared (NIR), red (R), green (G), or blue (B) wavelengths could be used to estimate GS‐25 tiller density across environments and (ii) if the inclusion of within‐field references would improve the estimation of GS‐25 tiller density for determining N recommendations. Research was conducted at four site‐years in 1998 and 1999 using two wheat varieties. At three locations, a randomized replicated strip‐plot design with three seeding rates was used. The fourth location was an on‐farm test with one seeding rate. Spectral indices and individual NIR, R, G, and B digital counts were tested for correlation with tiller density at each site. Tiller density at GS 25 and NIR digital counts were found to be consistently correlated (0.67 ≤ r ≤ 0.87). The inclusion of within‐field tiller density references resulted in a high correlation ( r = 0.88) between relative tiller density and relative NIR digital counts across environments. Using relative NIR digital counts to predict tiller density would have resulted in the correct N recommendation 82% of the time. DA - 2001/// PY - 2001/// DO - 10.2134/agronj2001.934783x VL - 93 IS - 4 SP - 783-789 SN - 1435-0645 ER - TY - JOUR TI - Phenotypic diversity of modern Chinese and North American soybean cultivars AU - Cui, ZL AU - Carter, TE AU - Burton, JW AU - Wells, R T2 - CROP SCIENCE AB - Chinese and North American (NA) soybean breeding programs have a 70‐yr history of genetic progress in relative isolation from each other. Because both programs rest upon a genetic base that is primarily Chinese in origin, the actual genetic distinctness of Chinese and NA breeding is not clear. The objectives of this study were to (i) develop a phenotypic similarity (PS) index for a large group of Chinese and NA cultivars, on the basis of biochemical, morphological, and agronomic traits, (ii) compare Chinese and NA cultivars for PS through cluster analysis, and (iii) use results to develop guidelines for management of the contrasting Chinese and NA breeding programs as reservoirs of diversity. Chinese (47) and NA (25) cultivars were evaluated for 25 traits in growth chambers. Traits pleiotropic to maturity were avoided. Significant ( P < 0.05) differences between Chinese and NA cultivars were noted for leaf and seed traits. Multivariate analysis captured 79% of the total genotypic variation among the 72 cultivars and was used to develop PS estimates. Cluster analysis of PS showed a much greater phenotypic diversity among Chinese than among NA cultivars and a striking distinctness between the two groups. The contrasting nature of Chinese and NA cultivars in this study is theorized to reflect that (i) the NA cultivars may trace to a subset of the Chinese cultivar genetic base, and/or (ii) Chinese and NA cultivars may have diverged phenotypically via breeder selection pressure. Cluster results here, based on PS, agreed roughly with previous cluster analyses, which were derived from pedigree analysis. The physical distinctness of NA and Chinese cultivars shows that introgression of Chinese cultivars into NA breeding should broaden NA germplasm's agronomic, morphological, and biochemical diversity. Introgression may be accomplished most effectively by avoiding matings of Chinese and NA cultivars from the same phenotypic cluster. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.1954 VL - 41 IS - 6 SP - 1954-1967 SN - 0011-183X ER - TY - CHAP TI - Peanut roast color and sensory attribute relationships AU - Pattee, H. E. AU - Sanders, T. H. AU - Isleib, T. G. AU - Giesbrecht, F. G. T2 - Chemistry and physiology of selected food colorants A2 - J. M. Ames, A2 - Hofmann, T. F. AB - Peanut roasting develops not only a pleasing sensory flavor but also a pleasing color. In studying the genetic relationships between sensory attributes and peanut genotypes, roast color of the peanut paste test sample is an important source of variability that must be considered. Intensity of the roasted peanut sensory attribute has a quadratic relationship to CIELAB L* with an optimum for roast color at 58.7. Changes in roasted peanut, sweet, bitter, and astringent sensory attributes as roasting progresses are discussed as are the effects of peanut market-type on the intensity and rate of change in the sensory attributes. Differences in the roasted peanut quality of the peanut market-types point to the importance of cooperative efforts between plant breeders and food scientists to ensure that when new varieties are released they not only have superior agronomic characteristics but also maintain or improve upon the flavor quality characteristics. CN - TP456.C65 C48 2001 PY - 2001/// DO - 10.1021/bk-2001-0775.ch013 SP - 187-200 PB - Washington, DC: American Chemical Society ER - TY - JOUR TI - Genotypic rankings for aluminum tolerance of soybean roots grown in hydroponics and sand culture AU - Villagarcia, MR AU - Carter, TE AU - Rufty, TW AU - Niewoehner, AS AU - Jennette, MW AU - Arrellano, C T2 - CROP SCIENCE AB - Screening methodology remains a practical barrier in the breeding of Al‐tolerant soybean [ Glycine max (L.) Merr.]. Our objectives were to (i) develop a repeatable sand‐media culture method for Al tolerance screening of plants, (ii) compare Al response of genotypes in sand culture to a standard hydroponics‐based seedling culture, and (iii) establish a practical guide for the use of hydroponics and sand‐culture screening methods in the selection of Al‐tolerant soybean. We developed a sand‐media culture method and imposed 0 and 450 μ M Al 3+ activity treatments upon 10 diverse soybean genotypes. The experiment employed a randomized complete block design with nine replications. Root weight and relative root surface area (RRSA) were determined at 18 d after transplanting (DAT). In hydroponics, the genotypes were compared for taproot elongation after 3 d of exposure to 0, 2, and 5 μ M Al 3+ activity treatments in a split plot design with six replications. Aluminum stress was imposed successfully (approximately 57% of the growth in control) in hydroponics and sand culture, but discrepancies between methods were apparent. The hydroponics‐based seedling screen produced an inflated range of genotypic response and altered Al tolerance rankings in comparison with sand culture. ‘Perry’, which was tolerant to Al in sand culture, was remarkably sensitive to Al in hydroponics. Despite the discrepancies, seedling‐based screening successfully identified three (PI 417021, PI 416937, and Biloxi) of the four genotypes that were most tolerant to Al in sand culture. Results suggested that seedling screens can play a practical role in breeding. However, their application to a specific breeding population should be validated with older plants and solid media. The RRSA appeared to be a promising measure of A1 tolerance for soybean roots. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4151499x VL - 41 IS - 5 SP - 1499-1507 SN - 1435-0653 ER - TY - JOUR TI - Genetic background and environment influence palmitate content of soybean seed oil AU - Rebetzke, GJ AU - Pantalone, VR AU - Burton, JW AU - Carter, TE AU - Wilson, RF T2 - CROP SCIENCE AB - Dietary concerns over high saturates contained in edible vegetable oils has stimulated development of soybean [ Glycine max (L.) Merr.] cultivars with reduced palmitate content. Little is known of factors that might influence phenotypic expression of palmitate content among soybean populations varying for presence of a major reduced palmitate allele. The objective of this study was to investigate how environment and genetic background influence palmitate content when introducing the reduced palmitate trait into adapted backgrounds. Crosses were made between reduced palmitate germplasm, N87‐2122‐4 (53 g kg −1 palmitate) and normal palmitate cultivars, A3733, Burlison, Kenwood, P9273, and P9341 (103–123 g kg −1 palmitate). For each cross, F 4:6 lines homozygous for major reduced or normal palmitate alleles were bulked separately into Maturity Groups (MG) II, III, IV, and V, and evaluated in 10 contrasting field environments during 1993. Palmitate content varied between 82 and 90 g kg −1 across southern U.S. and Puerto Rican environments. Much of this environmental variation was associated with changes in minimum temperature during the growing season. Genetic background effects were highly significant ( P < 0.01) with cross means for palmitate content ranging between 81 and 93 g kg −1 Across different maturity groups, palmitate content of the progeny was correlated ( r = 0.94–0.99, P < 0.05) with mean content of the normal palmitate parent, such that for every 1 g kg −1 palmitate increase in the normal palmitate parent there was a 0.32 to 0.51 g kg −1 palmitate increase in the progeny. Genetic background effects were presumed to be associated with action of minor alleles transmitted from the normal palmitate parent. Presence of the reduced palmitate allele was associated with significantly ( P < 0.01) lower stearate (−6 to −13%) and higher oleate (+4 to +10%) contents across all maturity groups. Selection of low palmitate, high‐yielding parents should further decrease palmitate content and produce correlated improvements in stearate and oleate contents to improve overall oil quality in progeny containing reduced palmitate alleles. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.1731 VL - 41 IS - 6 SP - 1731-1736 SN - 0011-183X ER - TY - JOUR TI - Factors influencing tissue culture responses of mature seeds and immature embryos in turf-type tall fescue AU - Bai, Y AU - Qu, R T2 - PLANT BREEDING AB - Abstract In an effort to optimize tissue culture responses of turf‐type tall fescue for genetic transformation, the effects of five culture medium supplements on tissue culture responses were investigated with immature embryos and mature seeds of an elite cultivar, ‘Coronado’, as explant tissues. For both explants, calli induced on 6‐benzylaminopurine (BAP)‐containing medium had significantly improved regeneration ability. The optimal concentration of BAP for the induction of regenerable callus from mature seeds was 0.1 mg/l. Thidiazuron also improved callus regeneration frequency of mature seeds. Casein hydrolysate, L‐proline and myo‐inositol improved callus induction of immature embryos but not mature seeds. They did not improve callus regeneration frequencies with either explant tissue. By simply slicing the mature seeds into two halves longitudinally, the callus induction frequencies, as well as the corresponding overall plant regeneration frequencies, were increased approximately three‐ to six‐fold in all three combinations of 2,4‐dichlorophenoxyacetic acid and BAP in callus induction media. DA - 2001/6// PY - 2001/6// DO - 10.1046/j.1439-0523.2001.00594.x VL - 120 IS - 3 SP - 239-242 SN - 0179-9541 KW - Festuca arundinacea KW - 6-benzylaminopurine KW - casein hydrolysate KW - L-proline KW - myo-inositol KW - thidiazuron ER - TY - JOUR TI - Efforts to initiate construction of a disease resistance package on a designer chromosome in tobacco AU - Lewis, RS AU - Wernsman, EA T2 - CROP SCIENCE AB - Gene cloning and transformation can be used to circumvent linkage drag effects that can plague conventional interspecific gene transfers. These techniques can also be used to create desirable genetic linkages. Use of Nicotiana glutinosa L. N ‐gene mediated TMV (tobacco mosaic virus) resistance in flue‐cured tobacco, N tabacum L., has been limited due to linkage drag effects. Transformation was used to introduce the cloned N ‐gene into NC152, a chromosome addition line possessing a chromosome pair from N africana. This chromosome has been proposed to be used as a “designer chromosome” into which numerous transgenes could be inserted to form a desirable linkage package. The system could be used to shuttle a large number of transgenes from genotype to genotype. One hundred thirty‐six primary transformants possessing the N transgene were produced and hybridized with TMV‐susceptible ‘Petite Havana.’ These may serve as valuable TMV‐resistant breeding materials. For each independent transformant, BC 1 F 1 families which segregated for TMV resistance and the addition chromosome were generated. Data from cosegregation, transmission, and molecular analyses were used to conclude that one transformant possessed an insertion of the N ‐gene in the addition chromosome. By inserting N in the chromosome, we initiated construction of a disease resistance package by linking the TMV resistance gene with a potyvirus resistance gene(s) native to the chromosome. Occasional loss of the transgene, however, may be evidence of previously undetected interchromosomal recombination, and may have implications for use of this system in cultivar development. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4151420x VL - 41 IS - 5 SP - 1420-1427 SN - 0011-183X ER - TY - PCOMM TI - Dwarf8 polymorphisms associate with variation in flowering time AU - Thornsberry, JM AU - Goodman, MM AU - Doebley, J AU - Kresovich, S AU - Nielsen, D AU - Buckler, ES DA - 2001/7// PY - 2001/7// DO - 10.1038/90135 SP - 286-289 ER - TY - JOUR TI - Bonding of Hg(II) to reduced organic, sulfur in humic acid as affected by S/Hg ratio AU - Hesterberg, D AU - Chou, JW AU - Hutchison, KJ AU - Sayers, DE T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Organic matter is an important sorbent of heavy metals in soils and sediments. The heterogeneity of organic matter, including the presence of various reactive O-, N-, and S-bearing ligands, makes it difficult to precisely characterize the nature of metal-ligand binding sites. The objective of this research was to characterize the extent and nature of Hg(II) bonding with reduced organic S in soil organic matter. Sulfur-rich humic acid (0.7 +/- 0.1 mol of S kg-1) was extracted from samples of surface soil from a marine wetland. Synchrotron X-ray absorption near-edge structure (XANES) analysis at the S K edge indicated that 70 +/- 3 mol % of the organic S was in a reduced oxidation state. Aqueous solutions containing 2 mmol of Hg kg-1, 0.1 M NaNO3, and humic acid added at various S/Hg molar ratios at pH 5.60 +/- 0.02 were characterized using extended X-ray absorption fine structure (EXAFS) spectroscopy at the Hg LIII edge. Spectral fitting showed that as the total S/Hg ratio increased from 0.6 to 5.6 (reduced S/Hg of 0.4-4.0), the fraction of Hg-S bonding relative to Hg-O (or Hg-N) bonding increased from 0.4 to 0.9. Results demonstrated preferential bonding of Hg(II) to reduced organic S sites and indicated that multiple sulfur ligands were coordinated with Hg2+ ions at high S/Hg ratios, which corresponded to low levels of complexed Hg(II). DA - 2001/7/1/ PY - 2001/7/1/ DO - 10.1021/es001960o VL - 35 IS - 13 SP - 2741-2745 SN - 1520-5851 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035387905&partnerID=MN8TOARS ER - TY - JOUR TI - Allocation of nitrogen and dry matter for two soybean genotypes in response to water stress during reproductive growth AU - Chipman, RB AU - Raper, CD AU - Patterson, RP T2 - JOURNAL OF PLANT NUTRITION AB - Drought stress significantly limits soybean [Glycine max (L.) Merr.] yield in the Southeastern United States. The Plant Introduction 416937 (PI), which has lower yields than adapted cultivars under favorable conditions but a relatively lesser yield reduction under water-stress conditions, has been identified as a potential source of drought avoidance germplasm. It is unclear whether the mechanism of drought avoidance is associated with shoot or root. Also unclear is the effect of the PI's restricted yield potential on the extent of its yield reduction in response to a water stress. To determine the differences in response between the PI and an adapted cultivar, Deltapine 105, to reproductive sink size and water stress, inoculated PI and Deltapine plants were grown in sand-filled pots in controlled-environment chambers. The fixed rooting volume of the pot culture restricts the influence that genotypic differences in rooting patterns may have in accessing soil water. During the 24-day period of pod development between R-3 and R-6 growth stages, plants were subjected to one of two water regimes, either well-watered or water-stressed to a leaf water potential of about −0.95 MPa. Within each water treatment, plants of both genotypes were depodded at the R3 stage to remove all pods (full depodding), one-half of the pods (partial depodding), or no pods (no depodding). Tissues of plants harvested at the R6 stage were separated, dried to a constant mass, weighed, and analyzed for nitrogen. Photosynthate production was calculated from dry matter and nitrogen content. Photosynthate production and nitrogen fixation by Deltapine plants were unaffected within a pod load by the mild water stress, but both photosynthate production and nitrogen fixation by the PI plants were diminished by the mild water stress except when a reproductive sink was absent. It thus appears that a sizeable component of the drought tolerance observed in field experiments for the PI plants may be attributed to root characteristics. Leaf nitrogen concentration decreased during water stress in Deltapine plants but not in the PI plants. Also, the decrease in nitrogen concentration in stems was greater in response to increased reproductive load for Deltapine plants than for the PI plants. These data suggest that the PI does not remobilize leaf nitrogen as readily as Deltapine. DA - 2001/// PY - 2001/// DO - 10.1081/PLN-100103779 VL - 24 IS - 6 SP - 873-884 SN - 0190-4167 ER - TY - JOUR TI - Allelopathic cover crops to reduce herbicide use in sustainable agricultural systems AU - Nagabhushana, G. G. AU - Worsham, A. D. AU - Yenish, J. P. T2 - Allelopathy Journal DA - 2001/// PY - 2001/// VL - 8 IS - 2 SP - 133-146 ER - TY - JOUR TI - Urea flux in beef steers: Effects of forage species and nitrogen fertilization AU - Archibeque, S. L. AU - Burns, J. C. AU - Huntington, G. B. T2 - Journal of Animal Science AB - The effects of two forage species and N levels on urea kinetics and whole-body N metabolism were evaluated in eight Angus steers (initial BW 217+/-15 kg). In a replicated, 4 x 4 Latin square design, steers were fed gamagrass (Tripsacum dactyloides L.) or switchgrass (Panicum virgatum L.), each of which had 56.2 (LO) or 168.5 (HI) kg of N fertilization per hectare. Diets provided adequate energy for 0.5 kg ADG. Nitrogen balance and urea kinetics were measured from d 22 to 27 of each period. Urine samples collected during intravenous infusion of bis 15N urea were used to calculate production and recycling of urea N from relative abundance of urea isotopomers. Jugular blood serum was analyzed for serum urea N (SUN). Gamagrass differed from switchgrass (P < 0.05) in daily DMI (4,273 vs 4,185 g), N intake (72 vs 67 g), DM digestibility (61.0 vs 63.6%), fecal N (30.6 vs 28.3 g/d), urine urea N (10.5 vs 8.0 g/d), and percentage of urinary N present as urea N (53.5 vs 40.0%). After adjustment for differences in N intake, fecal N still tended to be greater (P < 0.09) for gamagrass than for switchgrass. The LO differed from the HI (P < 0.01) in daily N intake (63 vs 76 g), DM digestibility (61.3 vs 63.3%), urine N (13.6 vs 25.9 g/d), and N retained as a percentage of N digested (57.3 vs 43.5%). Compared to switchgrass, gamagrass had greater SUN, N digestibility, and N digested as N level increased (forage x N level interactions, P < 0.05). As N level increased, N retention increased from 19.5 to 23.5 g/d in gamagrass and decreased from 20.5 to 18.1 g/d in switchgrass (interaction, P < 0.07). The HI group was greater than the LO intake group (P < 0.03) in endogenous production of urea N (44.4 vs 34.0 g/d), gut entry rate of urea N (31.6 vs 28.2 g/d), and the amount of urea N that re-entered the ornithine cycle (9.4 vs 7.9 g/d). However, the percentage of urea N entering the gastrointestinal tract that was recycled was constant among treatments (29.1%), indicating that almost 70% of the urea N that entered the gastrointestinal tract was potentially available for anabolic purposes of the steers as a component of microbial products that were absorbed or excreted in the feces. In summary, N levels affected N metabolism of steers more when they were fed gamagrass than when they were fed switchgrass. Although the absolute amounts of N moving through the system changed with variations in intake, the proportions remained similar, with a greater efficiency of N use at low N intakes. DA - 2001/// PY - 2001/// DO - 10.2527/2001.7971937x VL - 79 IS - 7 SP - 1937-1943 ER - TY - JOUR TI - Tracing nitrate transport and environmental impact from intensive swine farming using delta nitrogen-15 AU - Karr, JD AU - Showers, WJ AU - Gilliam, JW AU - Andres, AS T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Natural-abundance delta15N showed that nitrate generated from commercial land application of swine (Sus scrofa domesticus) waste within a North Carolina Coastal Plain catchment was being discharged to surface waters by ground water passing beneath the sprayfields and adjacent riparian buffers. This was significant because intensive swine farms in North Carolina are considered non-discharge operations, and riparian buffers with minimum widths of 7.6 m (25 ft) are the primary regulatory control on ground water export of nitrate from these operations. This study shows that such buffers are not always adequate to prevent discharge of concentrated nitrate in ground water from commercial swine farms in the Mid-Atlantic Coastal Plain, and that additional measures are required to ensure non-discharge conditions. The median delta15N-total N of liquids in site swine waste lagoons was +15.4 +/- 0.2% vs. atmospheric nitrogen. The median delta15N-NO3 values of shallow ground water beneath and adjacent to site sprayfields, a stream draining sprayfields, and waters up to 1.5 km downstream were + 15.3 +/- 0.2 to + 15.4 +/- 0.2%. Seasonal and spatial isotopic variations in lagoons and well waters were greatly homogenized during ground water transport and discharge to streams. Neither denitrification nor losses of ammonia during spraying significantly altered the bulk ground water delta15N signal being delivered to streams. The lagoons were sources of chloride and potassium enrichment, and shallow ground water showed strong correlation between nitrate N, potassium, and chloride. The 15N-enriched nitrate in ground water beneath swine waste sprayfields can thus be successfully traced during transport and discharge into nearby surface waters. DA - 2001/// PY - 2001/// DO - 10.2134/jeq2001.3041163x VL - 30 IS - 4 SP - 1163-1175 SN - 1537-2537 ER - TY - JOUR TI - Stability of reduced organic sulfur in humic acid as affected by aeration and pH AU - Hutchison, KJ AU - Hesterberg, D AU - Chou, JW T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Reduced S groups in soil organic matter (OM) play an important role in the complexation of heavy metals. These complexation reactions are often studied using the humic acid component of OM. The objective of our study was to determine the effect of pH on humic acid yield and the effect of pH and exposure to O 2 on the oxidation of reduced organic S. Humic acid was extracted at pH levels between 11.5 and 13.0 from a soil collected from a salt marsh. Also, aqueous samples of humic acid at different pH levels were aspirated with CO 2 ‐free air for 4 or 44 h. X‐ray absorption near‐edge structure (XANES) spectroscopy was used to determine changes in S oxidation states for the various treatments. With increasing pH, the yield of humic acid increased from 1.3 to 4.6 g humic acid kg −1 soil, and the total S in these samples was 24 ± 1 g kg −1 humic acid. Linear‐combination fitting of XANES spectra showed that all of these humic acid samples contained ≈70% (mol/mol) reduced S (modeled as benzyl disulfide) and 30% (mol/mol) oxidized S (modeled as sulfonate and ester sulfate). For humic acid exposed to aeration for 4 h at pH levels between 11.5 and 13.0, reduced organic S was oxidized only at pH 13.0 (15% [mol/mol] of total S). Samples exposed to aeration for 44 h between pH 3.5 and 12.4 showed no detectable change in reduced organic S. DA - 2001/// PY - 2001/// DO - 10.2136/sssaj2001.653704x VL - 65 IS - 3 SP - 704-709 SN - 0361-5995 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034977841&partnerID=MN8TOARS ER - TY - JOUR TI - Spatial variability of water and bromide transport through variably saturated soil blocks AU - Strock, JS AU - Cassel, DK AU - Gumpertz, ML T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Water and solute transport pathways through soil are very complex. Soil properties affecting solute transport vary spatially and temporally within a soil profile and across landscape positions. The objective of this laboratory study was to evaluate water and bromide (Br) transport through 38‐ by 38‐ by 60‐cm‐deep undisturbed blocks of Cecil soil (Clayey, kaolinitic, thermic Typic Kanhapludults) collected from three contrasting landscape positions (interfluve, linear slope, and foot slope) in the Piedmont region of North Carolina. Two replicate soil blocks from each position were placed on a grid lysimeter‐plate effluent collection system which facilitated collection of the effluent from 81 discrete cells under −2.5 kPa pressure. Each block was equilibrated for 5 d with a once daily application of 3.5 L of 0.005 M CaSO 4 solution by a water drop applicator at a rate of 14 mm h −1 Four‐hundred mL of KBr solution (4000 g Br m −2 ) was uniformly sprayed onto the soil surface. Thereafter, 3.5 L of 0.005 M CaSO 4 solution was applied daily for the duration of each experiment (19–33 d). Effluent volume and Br concentration in the effluent were measured daily for each of the 81 4 by 4‐cm cells. Cumulative water outflow and Br distribution plots, spatial distribution of cumulative effluent percent, frequency plots, and Br breakthrough curves (BTCs) showed that differences in preferential flow of water and Br occurred for soil blocks from different landscape positions. Differences in preferential flow of water and Br were attributed to soil horizon thickness, soil texture and structure, macroporosity, and slope gradient. Preferential flow of water and Br under variably saturated conditions was found to be highly variable within a given soil profile and that differences in the distribution and magnitude of preferential flow occurred across topographic positions. DA - 2001/// PY - 2001/// DO - 10.2136/sssaj2001.1607 VL - 65 IS - 6 SP - 1607-1617 SN - 1435-0661 ER - TY - JOUR TI - Spatial and time distribution of dairy cattle excreta in an intensive pasture system AU - White, SL AU - Sheffield, RE AU - Washburn, SP AU - King, LD AU - Green, JT T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - ABSTRACT This study determined distribution of feces and urine from 36 lactating dairy cattle ( Bos taurus ) managed in a rotationally grazed 0.74‐ha endophyte‐free tall fescue ( Festuca arundinacea Schreb.)–white clover ( Trifolium repens L.) pasture. Cows were observed for 24 h five times from July 1997 to April 1998, and for 13.5 h in September 1997. During each 24‐h observation period, the first grazing period (12 h) used 54% of the paddock and the second grazing period (8 h) used the entire paddock. Times and locations of all defecations and urinations from a subgroup of eight cows, observed while in the pasture, feed area, milking parlor, or in transit were recorded during the observation periods listed above and another time in May 1997. On pasture, all defecations and urinations were surveyed and mapped for all 36 cows. Feces and urine from six observation periods covered an estimated 10% of the paddock area in one year. Within 30 m of the water tank, concentrations of feces and urine from three warm‐season observations were significantly greater than concentrations during three cool‐season observations. Percentages of defecations and urinations on the pasture, feeding, and milking areas were highly correlated ( r > 0.90) with time spent in those areas. Pasture‐based systems could reduce manure handling and storage requirements proportional to the time cattle are on pastures. Manure on the pasture was evenly distributed, except around the water tank during warm‐weather grazings. Results indicate that pasture‐based dairy systems may require smaller, less‐expensive manure management systems compared with confinement dairy farms. DA - 2001/// PY - 2001/// DO - 10.2134/jeq2001.2180 VL - 30 IS - 6 SP - 2180-2187 SN - 0047-2425 ER - TY - JOUR TI - Plant growth regulator and mowing height effects on seasonal root growth of penncross creeping bentgrass AU - Fagerness, MJ AU - Yelverton, FH T2 - CROP SCIENCE AB - Summer decline of creeping bentgrass [ Agrostis palustris Huds. (= Agrostis stolonifera var. palustris (Huds.) Farw.] root growth is an annual concern in many regions of the USA. A 2‐yr field study was conducted to investigate the effects of mowing height and plant growth regulator (PGR) treatments on root biomass (RB) patterns in ‘Penncross’ creeping bentgrass, grown on a Wakulla sand (sandy, siliceous, Thermic Psammentic Hapludults) with 94% sand, 4% silt, 2% clay, 24 mg g −1 organic matter, and a pH of 6.1. Plots were maintained at 3.2, 4.0, or 4.8 mm throughout the experiment. Plant growth regulator treatments were trinexapac‐ethyl, [4‐(cyclopropyl‐α‐hydroxymethylene)‐3,5‐dioxo‐cyclohexane carboxylic acid ethyl ester] applied at 0.05 kg a.i. ha −1 and paclobutrazol, {(±)‐(R*,R*)‐β‐[(4‐chloro‐phenyl)methyl]‐α‐(1,1‐dimethylethyl)‐1H‐1,2,4‐triazole‐1‐ethanol} applied at 0.14, 0.28, or 0.56 kg a.i. ha −1 Plant growth regulator treatments initially were applied in April 1997 and were reapplied monthly for 24 mo. Annual variation in air and soil temperature accounted for variable RB across years. Root biomass declined 76% from a May maximum to a minimum in September; however, RB increased between September and January. Turf mowed to a height of 3.2 mm consistently had lower RB than turf maintained at 4.0 or 4.8 mm, and had slower early autumn RB recovery. When averaged across mowing heights, only paclobutrazol (0.56 kg a.i. ha −1 ) reduced RB and no PGR increased rooting when compared with nontreated turf. From September to January of each year, a PGR by mowing height interaction showed that paclobutrazol applied at 0.56 kg a.i. ha −1 delayed RB recovery in turf mowed to a height of 4.8 mm, while no PGR delayed RB recovery in turf maintained at the 3.2 mm mowing height. Slower RB recovery in turf mowed to 3.2 mm following the September minimum RB was attributed to reductions in turf quality and density, rather than the effects of PGRs. Paclobutrazol only reduced Penncross RB when applied at twice the labeled rate and with greater application frequency than is typical for most PGR use patterns. These results showed that labeled rates of paclobutrazol and trinexapac‐ethyl did not adversely affect root growth under putting green conditions. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.1901 VL - 41 IS - 6 SP - 1901-1905 SN - 0011-183X ER - TY - JOUR TI - Nitrogen-15 recovery in soil incubated with potassium nitrate and clover residues AU - Muriuki, AW AU - King, LD AU - Volk, RJ T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - In the southeastern USA, legumes are used as green manure to meet crop N requirements of a following crop, but recovery is usually lower than from conventional fertilizers. We conducted a laboratory study for 26 wk under aerobic conditions to monitor recovery of 15 N‐labeled KNO 3 (fertilizer) and crimson clover ( Trifolium incarnatum L.) residues (clover) in organic, inorganic, and microbial biomass N pools. Volatilization of NH 3 from decomposing clover residues was monitored for 12 wk. Three hundred–gram samples of a Typic Kanhapludult soil were amended with N (0.051 mg N kg −1 dry soil in fertilizer and 0.049 mg N kg −1 dry soil in clover). A control with no N was also included. Although inorganic N (NH 4 , NO 2 , and NO 3 ) accumulated throughout (fertilizer > clover > control), the rate of accumulation did not differ among treatments. Organic and microbial biomass N concentration did not differ among treatments, but applied N recovery in microbial biomass was greater in clover than fertilizer ( P < 0.05) throughout. Ammonia volatilized was negligible. After 26 wk, applied N recovered in soil inorganic N was 66% for fertilizer and 40% for clover; in soil organic N, 18% for fertilizer and 50% for clover; and in microbial biomass N, 0.75% for fertilizer and 1.5% for clover. Applied N presumed denitrified was 16% in fertilizer and 10% in clover. We concluded that clover green manure can meet the N requirements of a following crop from the time of emergence in the southeastern USA. DA - 2001/// PY - 2001/// DO - 10.2136/sssaj2001.6551430x VL - 65 IS - 5 SP - 1430-1436 SN - 0361-5995 ER - TY - JOUR TI - Influence of environmental nutrient conditions on Gymnodinium breve (Dinophyceae) population dynamics: a numerical study AU - Liu, G AU - Janowitz, GS AU - Kamykowski, D T2 - MARINE ECOLOGY PROGRESS SERIES AB - MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 213:13-37 (2001) - doi:10.3354/meps213013 Influence of environmental nutrient conditions on Gymnodinium breve (Dinophyceae) population dynamics: a numerical study Gang Liu, Gerald S. Janowitz*, Daniel Kamykowski Department of Marine, Earth & Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208, USA *Corresponding author. E-mail: janowitz@ncsu.edu ABSTRACT: A model of Gymnodinium breve population dynamics modified from Liu et al. (2001; Mar Ecol Prog Ser 210:101-124) is used to investigate the influence of various nutrient conditions on the population increase of an alongshore population filament of G. breve cells as it moves onshore across a continental shelf. The environmental conditions in the model are derived from measurements or theory applicable to bloom development on the west Florida shelf. The simulations indicate that the potential nutrient input patterns here represented by nitrogen sources on the shelf, i.e., offshore, mid-shelf and coastal upwellings, a Trichodesmium-released surface nitrogen source associated with multi-nutrient ocean fertilization by air-borne dust input, and a coastal surface plume are all eligible to trigger and/or support a G. breve bloom. However, the occurrence, timing, location, duration, and intensity of the bloom are determined by nitrogen concentration, input location, and temporal availability. Some nitrogen support at the offshore initiation stage of population growth may induce earlier bloom development, but without additional nitrogen input in coastal regions, the bloom may not fully develop. As long as the nitrogen is available continuously from offshore through coastal regions, a G. breve population can develop into a fish-killing intensity (1 to 2.5 x 105 cells l-1) in a month or so from a background concentration of <1000 cells l-1 with a maximum growth rate of ~0.16 doublings d-1. An explosive growth stage is not present for the total population in the simulations in which fish-killing cell concentrations are developed in 30 d. However the illusion of explosive growth may be created by the first appearance of a high G. breve population density at the surface late in bloom development. In some cases, daily averaged surface concentration can increase by a factor of 10 in 2 d and increase from a background level of 500 cells l-1 to bloom levels of 104 cells l-1 in 8 d due primarily to surface accumulation resulting from appropriately directed swimming behavior. This numerical investigation further demonstrates that the vertical migration of G. breve can play a critical role not only in the efficient utilization of natural resources, but also in the population distribution. KEY WORDS: Model · Dinoflagellate · Gymnodinium breve · Population dynamics · Behavior · Nutrients Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 213. Online publication date: April 04, 2001 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2001 Inter-Research. DA - 2001/// PY - 2001/// DO - 10.3354/meps213013 VL - 213 SP - 13-37 SN - 1616-1599 KW - model KW - dinoflagellate KW - Gymnodinium breve KW - population dynamics KW - behavior KW - nutrients ER - TY - JOUR TI - Induction of lipid metabolic enzymes during the endoplasmic reticulum stress response in plants AU - Shank, KJ AU - Su, P AU - Brglez, I AU - Boss, WF AU - Dewey, RE AU - Boston, RS T2 - PLANT PHYSIOLOGY AB - Abstract The endoplasmic reticulum (ER) stress response is a signal transduction pathway activated by the perturbation of normal ER metabolism. We used the maize (Zea mays)floury-2 (fl2) mutant and soybean (Glycine max) suspension cultures treated with tunicamycin (Tm) to investigate the ER stress response as it relates to phospholipid metabolism in plants. Four key phospholipid biosynthetic enzymes, including DG kinase and phosphatidylinositol (PI) 4-phosphate 5-kinase were up-regulated in the fl2 mutant, specifically in protein body fractions where the mutation has its greatest effect. The third up-regulated enzyme, choline-phosphate cytidylyltransferase, was regulated by fl2 gene dosage and developmental signals. Elevated accumulation of the fourth enzyme, PI 4-kinase, was observed in the fl2 endosperm and soybean cells treated with Tm. The activation of these phospholipid biosynthetic enzymes was accompanied by alterations in membrane lipid synthesis and accumulation. The fl2 mutant exhibited increased PI content in protein body membranes at 18 d after pollination and more than 3-fold higher triacylglycerol accumulation in the endosperm by 36 d after pollination. Incorporation of radiolabeled acetate into phospholipids in soybean culture cells increased by about 30% with Tm treatment. The coordinated regulation of ER stress related proteins and multiple components of phospholipid biosynthesis is consistent with signaling through a common pathway. We postulate that the plant ER stress response has an important role in general plant metabolism, and more specifically in integrating the synthesis of protein and lipid reserves to allow proper seed formation. DA - 2001/5// PY - 2001/5// DO - 10.1104/pp.126.1.267 VL - 126 IS - 1 SP - 267-277 SN - 0032-0889 ER - TY - JOUR TI - Greenhouse evaluation of four boron fertilizer materials AU - Byers, DE AU - Mikkelsen, RL AU - Cox, FR T2 - JOURNAL OF PLANT NUTRITION AB - Management of boron (B) in soils can be difficult since a narrow range exists between plant deficiency and toxicity. A greenhouse study was conducted to evaluate the effectiveness of four soil-applied B fertilizers varying in solubility (Granubor, Hydroboracite, Ulexite, and Colemanite) in supplying B to alfalfa (Medicago sativa L.). Boron was incorporated at rates of 0, 1, or 2 mg B kg−1 into Norfolk (fine-loamy, kaolinitic, thermic, Typic Kandiudults) or a Cecil (fine, kaolinitic, thermic Typic Kanhapludults) soil and planted with alfalfa. After establishment, shoots were harvested four times at approximately five-week intervals and analyzed for dry matter and B. Following the last harvest, soil samples were taken and analyzed for Mehlich-1 extractable B. There was no effect of fertilizer material, application rate, or their interaction on the dry weight of alfalfa. Boron concentrations in alfalfa did not significantly decline with each successive cutting, indicating that a sufficient amount was applied for the duration of the study. In the first cutting, plants grown with Granubor and Ulexite had higher concentrations of B than those with Hydroboracite, which was in turn higher than Colemanite, reflecting differences in solubility. However, by the third and fourth cuttings, there were no significant differences in tissue B concentrations among the four fertilizer sources. This indicates that given adequate time, even less-soluble fertilizer sources may provide sufficient B to growing plants. DA - 2001/// PY - 2001/// DO - 10.1081/PLN-100103665 VL - 24 IS - 4-5 SP - 717-725 SN - 1532-4087 KW - boron fertilizer KW - Granubor KW - Colemanite KW - Ulexite KW - Hydroboracite KW - micronutrient KW - plant uptake KW - alfalfa KW - Medicago sativa ER - TY - JOUR TI - Functional genomics and cell wall biosynthesis in loblolly pine AU - Whetten, R AU - Sun, YH AU - Zhang, Y AU - Sederoff, R T2 - PLANT MOLECULAR BIOLOGY DA - 2001/// PY - 2001/// DO - 10.1023/A:1010652003395 VL - 47 IS - 1-2 SP - 275-291 SN - 1573-5028 KW - EST sequencing KW - microarrays KW - Pinus taeda KW - xylogenesis KW - wood formation ER - TY - JOUR TI - Establishment and early growth characteristics of six Paulownia genotypes for goat browse in Raleigh, NC, USA AU - Mueller, JP AU - Luginbuhl, JM AU - Bergmann, BA T2 - AGROFORESTRY SYSTEMS DA - 2001/// PY - 2001/// DO - 10.1023/A:1010641602384 VL - 52 IS - 1 SP - 63-72 SN - 1572-9680 KW - biomass KW - fodder tree KW - grazing KW - in vitro digestibility KW - herbage quality KW - silvo pastoral system ER - TY - JOUR TI - Animal powered tillage translocated soil affects nutrient dynamics and soil properties at Claveria, Philippines AU - Thapa, B. B. AU - Cassel, D. K. AU - Garrity, D. P. T2 - Journal of Soil & Water Conservation DA - 2001/// PY - 2001/// VL - 56 IS - 1 SP - 14-21 ER - TY - JOUR TI - A field method for determing percentage of coated sand grains AU - Lindbo, DL AU - Vepraskas, MJ AU - Rhoton, FE T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Several USDA‐NRCS hydric soil field indicators require estimation of the percentage of organic‐coated sand grains (black grains). For example, to meet the Dark Surface field indicator the soil layer must contain at least 70% coated (black) grains. Field experience has shown that the estimation of the percentage of coated sand grains is often subjective and highly variable from one soil scientist to another. In order to overcome this variability a set of standards was created using a mixture of black and light gray (representing uncoated grains) sand grains. Weighing out each component for the desired ratio and mixing them in a 47‐mm‐diam. petri dish we made a set of three standards consisting of 50, 70, and 90% black grains. To test the effectiveness of these standards, soil scientists estimated the percentage of coated grains from similarly prepared samples first without the use of the standards and then with the use of the standards for comparison. Individuals improved the accuracy of their estimates by 10 to 60% and their hydric soil identification by 16%. The standards are easily prepared, easy to use, and portable. DA - 2001/// PY - 2001/// DO - 10.2136/sssaj2001.653949x VL - 65 IS - 3 SP - 949-953 SN - 1435-0661 ER - TY - JOUR TI - Peanut response to tillage and fertilization AU - Jordan, DL AU - Barnes, JS AU - Bogle, CR AU - Naderman, GC AU - Roberson, GT AU - Johnson, PD T2 - AGRONOMY JOURNAL AB - Peanut ( Arachis hypogaea L.) in the USA is generally seeded after several primary tillage operations that may include disking, chisel plowing, moldboard plowing, and bedding (conventional tillage systems). Concerns over erosion and production costs have increased interest in reduced tillage systems. Production in reduced tillage systems minimizes ability to incorporate fertilizers below the pegging zone, and residue on soil surface could impact movement of calcium sulfate (CaSO 4 ) into the soil, reducing Ca availability to pegs. Research was conducted from 1997 through 1999 to compare peanut yield and gross economic value of virginia market type peanut planted in conventional and strip tillage systems. Preplant fertilizer did not affect response to tillage. Response did not differ among conventional tillage systems consisting of disk, disk and chisel, or disk and moldboard plow or among reduced tillage systems. Pod yield of peanut grown in the most effective conventional tillage system exceeded yield when peanut was strip‐tilled into stubble of the previous crop, strip‐tilled into a wheat ( Triticum aestivum L.) cover crop, or strip‐tilled into beds prepared the previous fall without a cover crop. Tillage system and CaSO 4 rate affected pod yield and gross value independently. Gross value increased when CaSO 4 was applied regardless of tillage system. These data suggest that preplant fertilizer at relatively low, remedial rates does not affect peanut response to tillage systems. These data also suggest that tillage system does not have a major impact on peanut response to CaSO 4 . Collectively, these data indicate that the highest peanut yields occur in conventional tillage systems. DA - 2001/// PY - 2001/// DO - 10.2134/agronj2001.9351125x VL - 93 IS - 5 SP - 1125-1130 SN - 1435-0645 ER - TY - JOUR TI - Molecular scale characteristics of Cu(II) bonding in goethite-humate complexes AU - Alcacio, TE AU - Hesterberg, D AU - Chou, JW AU - Martin, JD AU - Beauchemin, S AU - Sayers, DE T2 - GEOCHIMICA ET COSMOCHIMICA ACTA AB - —Interactions between oxide minerals and natural organic matter affect metal adsorption properties of mineral surfaces, but the mechanisms of metal bonding are not well understood. Extended X-ray absorption fine structure (EXAFS) spectroscopy analyses were performed on aqueous pastes containing Cu(II) and goethite (α-FeOOH) with humic acid adsorbed at 0, 14, 28, 57, 88, 216, and 236 g kg−1 goethite, and with aqueous suspensions of humic acid only. Analyses were conducted at the Cu K edge with 40 mmol Cu(II) kg−1 goethite or 2 mmol Cu(II) kg−1 suspension for the humic acid system. Samples were equilibrated at pH 5.6 in a 0.1 M NaNO3 background electrolyte. For all systems, analysis of EXAFS results suggests that Cu(II) is present in a distorted octahedral configuration containing four short equatorial (1.94–1.97 Å) and two longer axial bonds with oxygen. When the concentration of adsorbed humic acid on goethite was increased from 0 to 28 g kg−1, the axial Cu-O bond length decreased to 2.24 ± 0.03 Å, which was less than for individual humic acid (2.32 ± 0.02 Å) or goethite (2.29 ± 0.03 Å) samples. The apparent decrease in the axial Cu-O bond length was attributed to a decrease in the ligand field splitting energy. When humic acid ligands replace equatorial water molecules in the Cu(II) coordination sphere, a weaker ligand field strength occurs. For absorbed humic acid up to 88 g kg−1 goethite, second-shell iron neighbors were observed between 3.17 and 3.20 Å, suggesting that Cu(II) was bonded on average to both inorganic (goethite) and organic (humic acid) functional groups. In addition, derivative X-ray absorption near edge structure (XANES) spectra for Cu(II) on goethite–humate complexes (<88 g kg−1) were poorly fit by use of a linear combination of spectra for Cu(II) on goethite or humate alone. At humate concentrations between 216 and 236 g kg−1 goethite, second-shell iron neighbors could not be identified, and the Cu-Oaxial distance (2.32 ± 0.02 Å) and derivative XANES spectra strongly resembled that of Cu(II) adsorbed to humate only. Analysis of the XANES and EXAFS data suggested that Cu(II) was bonded on average to both inorganic and organic functional groups as a type A ternary complex at lower levels of adsorbed humate, and to organic groups as a type B complex at higher levels. DA - 2001/5// PY - 2001/5// DO - 10.1016/S0016-7037(01)00546-4 VL - 65 IS - 9 SP - 1355-1366 SN - 1872-9533 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035010875&partnerID=MN8TOARS ER - TY - JOUR TI - Metabolic mechanisms associated with alleles governing the 16 : 0 concentration of soybean oil AU - Wilson, RF AU - Marquardt, TC AU - Novitzky, WP AU - Burton, JW AU - Wilcox, , JR AU - Kinney, AJ AU - Dewey, RE T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Soybean [ Glycine max (L.) Merr.] oil typically contains ca. 11% palmitic acid, but germplasm has been developed with less than 4% to about 35% 16∶0, A number of recessive alleles associated with these phenotypes have been described thattrepresent different mutations at Fap loci, however, the gene products (enzymes) produced by these alleles are unknown. This work attempts to define the metabolic activities that are regulated by the fap 1 , fap 2 , and fap nc alleles in soybean. Observation of de novo synthesis and metabolic turnover of fatty acids esterified to phospholipids in cotyledons during the period of peak oil accumulation revealed genotypic differences in the supply of 16∶0‐CoA from plastids. These metabolic studies narrowed the identification of fap 1 , fap 2 , and fap nc alleles to the genes that encode or regulate the 3‐keto‐acyl‐ACP synthetase II (where ACP is acyl carrier protein), 16∶0‐ACP thioesterase, 18∶0‐ACP desaturase, or 18∶1‐ACP thioesterase enzymes. Kinetic analyses suggested that the fap 2 mutation results in a decreased 3‐keto‐acyl‐ACP synthetase II activity. Deficiencies in 16∶0‐ACP thioesterase activity represented the most likely explanation of fap 1 and fap nc gene function. This hypothesis was strongly supported by Northern blot assays that revealed a significant reduction in the accumulation of transcripts corresponding to the 16∶0‐ACP thioesterase in germplasm homozygous for the fap nc allele. DA - 2001/4// PY - 2001/4// DO - 10.1007/s11746-001-0265-4 VL - 78 IS - 4 SP - 335-340 SN - 1558-9331 KW - developing-seed KW - fap-alleles KW - genetics KW - glycerolipid composition KW - Glycine max KW - metabolism KW - oil KW - palmitic acid KW - phospholipid KW - saturated fat ER - TY - JOUR TI - Identification of a novel phosphorylation motif for CDPKs: Phosphorylation of synthetic peptides lacking basic residues at P-3/P-4 AU - Huang, JZ AU - Hardin, SC AU - Huber, SC T2 - ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS AB - The Ca(2+)-dependent protein kinases (CDPKs) are members of a large subfamily of protein kinases in plants that have been implicated in the control of numerous aspects of plant growth and development. One known substrate of the CDPKs is the ER-located ACA2 calcium pump, which is regulated by phosphorylation of Ser(45). In the present study, a synthetic peptide based on the known regulatory phosphorylation site (RRFRFTANLS(45)KRYEA) was efficiently phosphorylated in vitro by CDPKs but not a plant SNF1-related protein kinase. Phosphorylation of the Ser(45)-ACA2 peptide was surprising because the sequence lacks basic residues at P-3/P-4 (relative to the phosphorylated Ser at position P) that are considered to be essential recognition elements for CDPKs. We demonstrate that phosphorylation of the Ser(45)-ACA2 peptide is dependent on the cluster of basic residues found N-terminal (P-6 to P-9) as well as C-terminal (P + 1/P + 2) to the phosphorylated Ser. The results establish a new general phosphorylation motif for CDPKs: [Basic-Basic-X-Basic]-phi-X(4)-S/T-X-Basic (where phi is a hydrophobic residue). The motif predicts a number of new phosphorylation sites in plant proteins. Evidence is presented that the novel motif may explain the phosphorylation by CDPKs of Ser271 in the aquaporin PM28A. DA - 2001/9/1/ PY - 2001/9/1/ DO - 10.1006/abbi.2001.2476 VL - 393 IS - 1 SP - 61-66 SN - 0003-9861 KW - calcium-dependent protein kinase KW - phosphorylation motif KW - synthetic peptide phosphorylation KW - Ca2+-ATPase KW - aquaporin ER - TY - JOUR TI - Effect of alleles governing 16 : 0 concentration on glycerolipid composition in developing soybeans AU - Wilson, RF AU - Marquardt, TC AU - Novitzky, WP AU - Burton, JW AU - Wilcox, , JR AU - Dewey, RE T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Soybean [ Glycine max (L.) Merr.] oil typically contains 11% palmitic acid, but germplasm with recessive alleles at Fap gene loci exhibit from less than 4% to about 35% 16:0, Although these alleles are used to develop new cultivars, little is known about how they influence palmitic acid concentration. One theory suggests that fap alleles may mediate differences in triacylglycerol composition through genetic effects on the activity or substrate specificity of acyltransferases, such as diacylglycerol acyltransferase (EC 2.3.1.20). Based on logistic function analysis of developing seed, differences in fag allele expression are evident in the rate of palmitic acid accumulation in triacylglycerol, with peak deposition near mid‐seed fill. Acetate saturation kinetics also reveal a strong positive relation between the relative amount of de novo palmitic acid synthesis and the indigenous palmitic acid concentration in triacylglycerol among fap genotypes. However, no differences appear in the kinetics of palmitoyl‐CoA metabolism in developing seed of these genotypes. Therefore, the fap alleles apparently do not encode or regulate the activities of glycerolipid acyltransferase enzymes. Rather, major genetic effects on triacylglycerol composition accrue through regulation of palmitic acid production in the plastids of developing soybean cotyledons. DA - 2001/4// PY - 2001/4// DO - 10.1007/s11746-001-0264-5 VL - 78 IS - 4 SP - 329-334 SN - 1558-9331 KW - developing-seed KW - fap-alleles KW - genetics KW - glycerolipid composition KW - Glycine max KW - logistic function KW - metabolism KW - oil KW - palmitic acid KW - saturated fat ER - TY - JOUR TI - Comparative effects of phytosterol oxides and cholesterol oxides in cultured macrophage-derived cell lines AU - Adcox, C AU - Boyd, L AU - Oehrl, L AU - Allen, J AU - Fenner, G T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - The cytotoxicity of cholesterol and a mixture of β-sitosterol/campesterol (50%/40%) and their oxides was examined in a cultured-derived macrophage cell line, C57BL/6. Cell numbers, lactate dehydrogenase (LDH) leakage, protein content, lipid uptake, and mitochondria dehydrogenase activity were determined after exposure of cell mononlayers to sterols and sterol oxides at a concentration of 200 μg/mL for up to 120 h. Results indicate that the oxides of cholesterol, β-sitosterol, and campesterol exhibited similar patterns of toxicity as indicated by LDH leakage, cell viability, and mitochondria dehydrogenase activity. Greatest cell damage was associated with treatments containing 5α,6α-epoxide or cholesterol oxides, followed by β-sitosterol/campesterol oxides, cholesterol, and β-sitosterol. The oxides of β-sitosterol/campesterol caused less LDH leakage and less of an effect on protein content. Results of this study demonstrate that phytosterols contained in vegetable oils, when subjected to frying conditions, do oxidize and may cause cellular damage in an in vitro cell line similar to cholesterol oxides, although less severe. Keywords: Phytosterols; cholesterol; sterol oxides; macrophage DA - 2001/4// PY - 2001/4// DO - 10.1021/jf001175v VL - 49 IS - 4 SP - 2090-2095 SN - 1520-5118 KW - phytosterols KW - cholesterol KW - sterol oxides KW - macrophage ER - TY - JOUR TI - Antioxidant properties of evening primrose seed extracts AU - Birch, AE AU - Fenner, GP AU - Watkins, R AU - Boyd, LC T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - The antioxidant activity of extracts of evening primrose seeds (SE) and a commercially extracted filter cake (FC) were determined. The SE and FC were extracted with methanol/water (9:1) followed by evaporation and concentration. Extracts were tested in a bulk oil system and an oil-in-water emulsion using safflower oil as the major source of lipids. The antioxidant activity of the extracts was compared to that of a control and to that of butylated hydroxytoluene (BHT), singly, and in combination. Antioxidant activity was measured by the co-oxidation of beta-carotene, an oxidative stability instrument, conjugated dienes, and headspace analysis of hexanal. The SE extract had greater antioxidant activity than the FC extract. The SE extract was more effective in controlling the oxidation in the oil-in-water model system than in the bulk oil system. The activity of SE was concentration dependent, and at higher concentrations the SE was as effective as BHT, but it required higher concentrations because of its lack of purity. Synergism between SE and BHT was demonstrated in both model systems. DA - 2001/9// PY - 2001/9// DO - 10.1021/jf010542f VL - 49 IS - 9 SP - 4502-4507 SN - 0021-8561 KW - evening primrose KW - antioxidants KW - oxidation ER - TY - JOUR TI - The use of mirrors during an assembly task: a study of ergonomics and productivity AU - Lutz, T. J. AU - Starr, H. AU - Smith, C. A. AU - Stewart, A. M. AU - Monroe, M. J. AU - Joines, S. M. B. AU - Mirka, G. A. T2 - Ergonomics AB - Industrial assembly tasks often require awkward, sustained neck and/or shoulder postures that can lead to increased musculoskeletal discomfort and reduced productivity. The aim of this study was to investigate the effects of mirror and periscope visual aids as ergonomic interventions designed to eliminate awkward postures of the cervicobrachial region during assembly tasks. Participants simulated a simple assembly task by using a cordless screwdriver to drive screws into a pre-tapped aluminium block. Trials of 15 min were run for each of four distinct assembly workstation configurations: industry standard (in-line screwdriver, work at elbow height, no visual aid); pistol grip (pistol grip screwdriver, work at shoulder height, no visual aid); mirror (in-line screwdriver, work at elbow height, single mirror visual aid); and periscope (in-line screwdriver, work at elbow height, two-mirror visual aid system). Muscular activity, discomfort, body posture, productivity and operator subjective assessment were recorded to determine the effects of the visual aid interventions. The results show that when comparing the interventions to the industry standard condition, there was a 45% reduction in average cervical erector spinae activity, a 90% reduction in average neck flexion angle and a 72% reduction in neck discomfort with the interventions. When comparing these interventions to the pistol grip condition there was an 80% reduction in activity of the dominant side deltoid, a 92% reduction in shoulder flexion angle and an 81% decrease in shoulder discomfort with the interventions. Productivity was greatest in the industry standard configuration followed by the pistol grip (9% lower), the periscope (13% lower) and the mirror (23% lower) configurations. A follow-up study that compared the productivity of the periscope configuration with that of the industry standard configuration showed that within a 4-h work period this productivity differential decreased by over 33%. DA - 2001/// PY - 2001/// DO - 10.1080/001401301750048222 VL - 44 IS - 2 SP - 215-228 ER - TY - JOUR TI - Structure of linkage disequilibrium and phenotypic associations in the maize genome AU - Remington, DL AU - Thornsberry, JM AU - Matsuoka, Y AU - Wilson, LM AU - Whitt, , SR AU - Doeblay, J AU - Kresovich, S AU - Goodman, MM AU - Buckler, ES T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - Association studies based on linkage disequilibrium (LD) can provide high resolution for identifying genes that may contribute to phenotypic variation. We report patterns of local and genome-wide LD in 102 maize inbred lines representing much of the worldwide genetic diversity used in maize breeding, and address its implications for association studies in maize. In a survey of six genes, we found that intragenic LD generally declined rapidly with distance ( r 2 < 0.1 within 1500 bp), but rates of decline were highly variable among genes. This rapid decline probably reflects large effective population sizes in maize during its evolution and high levels of recombination within genes. A set of 47 simple sequence repeat (SSR) loci showed stronger evidence of genome-wide LD than did single-nucleotide polymorphisms (SNPs) in candidate genes. LD was greatly reduced but not eliminated by grouping lines into three empirically determined subpopulations. SSR data also supplied evidence that divergent artificial selection on flowering time may have played a role in generating population structure. Provided the effects of population structure are effectively controlled, this research suggests that association studies show great promise for identifying the genetic basis of important traits in maize with very high resolution. DA - 2001/9/25/ PY - 2001/9/25/ DO - 10.1073/pnas.201394398 VL - 98 IS - 20 SP - 11479-11484 SN - 0027-8424 ER - TY - JOUR TI - Soybean as a receiver crop for nitrogen in swine lagoon effluent AU - Israel, DW AU - Mikkelsen, RL T2 - SOIL SCIENCE AB - Soybean (Glycine max L. Merr.) has been approved by the Natural Resource Conservation Service as a receiver crop for N in swine lagoon effluent applied to spray fields. However, its efficacy as a N receiver crop depends on the sensitivity of symbiotic N2 fixation to inhibition by N in the applied effluent. The objectives of this study were to use a 15N natural abundance method to (i) assess the degree of inhibition of symbiotic N2 fixation in soybean by applied effluent N and (ii) determine the quantity of effluent N removed from the soil in harvested seed of nodulating soybean. Two field experiments were conducted to evaluate seed yield; seed N accumulation and whole shoot N accumulation of nodulating and nonnodulating soybean cultivars supplied a range of N levels as either lagoon effluent or ammonium nitrate. Measurement of 15N natural abundances indicated that, on average, 27% of the N in seed of nodulating cultivars supplied 200 kg of plant-available N (PAN)/ha as swine lagoon effluent was derived from symbiotic N2 fixation. While this effluent N rate did not inhibit N2 fixation completely, seed N recovery of 100 kg effluent N/ha (1997 trial) and 64 kg effluent N/ha (1998 trial) was not different between the nodulating and nonnodulating cultivars. Similar recovery of effluent N in nodulating and nonnodulating cultivars, even though inhibition of N2 fixation by the nodulating cultivar was incomplete, resulted from the nodulating cultivars having higher yields and harvest indices than the nonnodulating cultivar. Subtraction of seed N at maturity from whole shoot N at the R6.5 growth stage (between full seed stage and physiological maturity) was used to estimate crop N returned to the soil. This estimate indicated that nodulating and nonnodulating cultivars returned similar amounts of N to the soil. Our results show that nodulating soybeans can recover as much applied effluent N in seed as a 6.3 Mg/ha (100 bu/ac) corn crop. DA - 2001/7// PY - 2001/7// DO - 10.1097/00010694-200107000-00003 VL - 166 IS - 7 SP - 453-464 SN - 1538-9243 KW - soybean KW - N-15 natural abundance KW - nitrogen receiver KW - nitrogen nutrition KW - lagoon effluent KW - waste management ER - TY - JOUR TI - Scanning electron microscopic study on in vitro somatic embryogenesis in perennial ryegrass and tall fescue AU - Bradley, D. E. AU - Bruneau, A. H. AU - Qu, R. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 IS - 2001 SP - 146-151 ER - TY - JOUR TI - Magnesium is more efficient than calcium in alleviating aluminum rhizotoxicity in soybean and its ameliorative effect is not explained by the Gouy-Chapman-Stern model AU - Silva, IR AU - Smyth, TJ AU - Israel, DW AU - Raper, CD AU - Rufty, TW T2 - PLANT AND CELL PHYSIOLOGY AB - The mechanistic basis for cation amelioration of Al rhizotoxicity in soybean was investigated through a series of studies comparing protective effects of Ca and Mg against Al inhibition of root elongation in a background 0.8 mM CaSO4 solution (pH 4.3). A modified Gouy-Chapman-Stern model was used to evaluate the effect of cations on electrical potential and Al3+ activity at root plasma membrane surfaces. Activities of Al3+ up to 4.6 µM in the background solution inhibited soybean tap root elongation by more than 80%. There was little or no response in root elongation when Ca and Mg were added to background solutions in the absence of Al. When added to Al-toxic solutions in the micromolar concentration range, Mg was 100-fold more effective than Ca in alleviating Al toxicity, whereas both cations were equally effective when added in the millimolar concentration range. The protective effect of micromolar additions of Mg on root elongation was specific for Al and it failed to alleviate La rhizotoxicity. In contrast to wheat, Mg amelioration of Al toxicity to soybean root elongation at low Mg concentration could not be explained by changes in potential and Al3+ activity at the root plasma membrane surfaces as predicted by a Gouy-Chapman-Stern model. These results suggest that Mg is not acting as an indifferent cation when present at low concentration and implies the involvement of a mechanism other than pure electrostatic effects at the root surface. DA - 2001/5// PY - 2001/5// DO - 10.1093/pcp/pce066 VL - 42 IS - 5 SP - 538-545 SN - 1471-9053 KW - aluminum toxicity KW - calcium KW - cation amelioration KW - Gouy-Chapman-Stern model KW - magnesium KW - soybean ER - TY - JOUR TI - Magnesium ameliorates aluminum rhizotoxicity in soybean by increasing citric acid production and exudation by roots AU - Silva, IR AU - Smyth, TJ AU - Israel, DW AU - Raper, CD AU - Rufty, TW T2 - PLANT AND CELL PHYSIOLOGY AB - Superior effectiveness of Mg over Ca in alleviating Al rhizotoxicity cannot be accounted for by predicted changes in plasma membrane Al3+ activity. The influence of Ca and Mg on the production and secretion of citrate and malate, and on Al accumulation by roots was investigated with soybean genotypes Young and PI 416937 which differ in Al tolerance. In the presence of a solution Al3+ activity of 4.6 microM, citrate and malate concentrations of tap root tips of both genotypes increased with additions of either Ca up to 3 mM or Mg up to 50 microM. Citrate efflux rate from roots exposed to Al was only enhanced with Mg additions and exceeded malate efflux rates by as much as 50-fold. Maximum citrate release occurred within 12 h after adding Mg to solution treatments. Adding 50 microM Mg to 0.8 mM CaSO4 solutions containing Al3+ activities up to 4.6 microM increased citrate concentration of tap root tips by 3- to 5-fold and root exudation of citrate by 6- to 9-fold. Plants treated with either 50 microM Mg or 3 mM Ca had similar reductions in Al accumulation at tap root tips, which coincided with the respective ability of these ions to relieve Al rhizotoxicity. Amelioration of Al inhibition of soybean root elongation by low concentrations of Mg in solution involved Mg-stimulated production and efflux of citrate by roots. DA - 2001/5// PY - 2001/5// DO - 10.1093/pcp/pce067 VL - 42 IS - 5 SP - 546-554 SN - 1471-9053 KW - aluminum tolerance KW - calcium KW - cation amelioration KW - magnesium KW - organic acids KW - root exudates KW - soybean ER - TY - JOUR TI - Hyperosmotic stress induces the rapid phosphorylation of a soybean phosphatidylinositol transfer protein homolog through activation of the protein kinases SPK1 and SPK2 AU - Monks, DE AU - Aghoram, K AU - Courtney, PD AU - DeWald, DB AU - Dewey, RE T2 - PLANT CELL AB - Although phosphatidylinositol transfer proteins (PITPs) are known to serve critical functions in regulating a varied array of signal transduction processes in animals and yeast, the discovery of a similar class of proteins in plants occurred only recently. Here, we report the participation of Ssh1p, a soybean PITP-like protein, in the early events of osmosensory signal transduction in plants, a function not attributed previously to animal or yeast PITPs. Exposure of plant tissues to hyperosmotic stress led to the rapid phosphorylation of Ssh1p, a modification that decreased its ability to associate with membranes. An osmotic stress-activated Ssh1p kinase activity was detected in several plant species by presenting recombinant Ssh1p as a substrate in in-gel kinase assays. Elements of a similar osmosensory signaling pathway also were conserved in yeast, an observation that facilitated the identification of soybean protein kinases SPK1 and SPK2 as stress-activated Ssh1p kinases. This study reveals the activation of SPK1 and/or SPK2 and the subsequent phosphorylation of Ssh1p as two early successive events in a hyperosmotic stress-induced signaling cascade in plants. Furthermore, Ssh1p is shown to enhance the activities of a plant phosphatidylinositol 3-kinase and phosphatidylinositol 4-kinase, an observation that suggests that the ultimate function of Ssh1p in cellular signaling is to alter the plant's capacity to synthesize phosphoinositides during periods of hyperosmotic stress. DA - 2001/5// PY - 2001/5// DO - 10.1105/tpc.13.5.1205 VL - 13 IS - 5 SP - 1205-1219 SN - 1532-298X ER - TY - JOUR TI - Genotypic control of high-frequency adventitious shoot regeneration via somatic organogenesis in loblolly pine AU - Tang, W AU - Whetten, R AU - Sederoff, R T2 - PLANT SCIENCE AB - Mature zygotic embryos of 24 genotypes of loblolly pine (Pinus taeda L.) were used as explants to establish an adventitious shoot regeneration system through somatic organogenesis. Callus formation frequencies of 18.2 (genotype 11-1103) -77.7% (genotype 7-100) have been induced from mature zygotic embryos of all genotypes tested on callus induction medium (basal salts) containing 2,4-dichlorophenoxyacetic acid (2,4-D) or alpha-naphthaleneacetic acid (NAA), 6-benzyladenine (BA), and kinetin. Adventitious shoot regeneration via organogenesis with the frequency of 5.4 (genotype 11-1103 and 7-2) -77.2% (genotype 8-1082) was obtained from callus and tissue cultures derived from mature zygotic embryos of 24 genotypes of loblolly pine. The highest mean number of 18 adventitious buds per piece of callus 0.5x0.5 cm(2) in size was obtained from genotype 8-1082. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg/l indole-3-butyric acid (IBA) and 1 mg/l BA. After rooting, regenerated plantlets were established in soil. These results suggested that adventitious shoot regeneration via somatic organogenesis was influenced by the genotypes. The in vitro regeneration procedure established in this investigation could be used for clonal micropropagation of some genotypes of loblolly pine, as well as for establishing a transformation system in coniferous species. DA - 2001/7// PY - 2001/7// DO - 10.1016/S0168-9452(01)00394-6 VL - 161 IS - 2 SP - 267-272 SN - 0168-9452 KW - Pinus taedu L. KW - organogenesis KW - adventitious shoot regeneration KW - callus induction frequency KW - differentiation frequency ER - TY - JOUR TI - Genetic transformation of elite cultivars of turf-type tall fescue (Festuca arundinacea) AU - Bai, Y. AU - Qu, R. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 IS - 2001 SP - 129-136 ER - TY - JOUR TI - Formation of chloropyromorphite in a lead-contaminated soil amended with hydroxyapatite AU - Ryan, JA AU - Zhang, PC AU - Hesterberg, D AU - Chou, J AU - Sayers, DE T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Conversion of soil Pb to pyromorphite [Pb5(PO4)3Cl] was evaluated by reacting a Pb contaminated soil collected adjacent to a historical smelter with hydroxyapatite [Ca5(PO4)3OH]. In a dialysis experiment where the soil and hydroxyapatite solids were placed in separate dialysis bags suspended in 0.01 M NaNO3 solution a crystalline precipitate, identified as chloropyromorphite, formed on the dialysis membrane containing the soil. The aqueous composition of the solution indicated that dissolution of solid-phase soil Pb was the rate-limiting step for pyromorphite formation. Addition of hydroxyapatite to the soil caused a decrease in each of the first four fractions of sequential extractable Pb and a 35% increase in the recalcitrant extraction residue. After a 240-d incubation at field-moisture content there was a further increase in the recalcitrant extraction residue fraction of the hydroxyapatite-amended soil to 45% of the total soil Pb. The increase in the extraction residue fraction in the hydroxyapatite amended 0-d incubated soil as compared to the control soil illustrates that the chemical extraction procedure itself caused changes in extractability. Thus, the chemical extraction procedure cannot easily be utilized to confirm changes occurring in amended soils. The further increase after the 240-d incubation implies that the reaction also occurs in the soil during incubation. Extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that after the 240-d incubation the hydroxyapatite treatment caused a change in the average, local molecular bonding environment of soil Pb. Low-temperature EXAFS spectra (chi data and radial structure functions--RSFs) showed a high degree of similarity between the chemical extraction residue and synthetic pyromorphite, providing additional evidence that the change of soil Pb to pyromorphite is possible by simple amendments of hydroxyapatite to soil. DA - 2001/9/15/ PY - 2001/9/15/ DO - 10.1021/es010634l VL - 35 IS - 18 SP - 3798-3803 SN - 0013-936X UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035884175&partnerID=MN8TOARS ER - TY - JOUR TI - Effects of cultivar, explant treatment, and medium supplements on callus induction and plantlet regeneration in perennial ryegrass AU - Bradley, D. E. AU - Bruneau, A. H. AU - Qu, R. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 IS - 2001 SP - 152-156 ER - TY - JOUR TI - Differential aluminum tolerance in soybean: An evaluation of the role of organic acids AU - Silva, IR AU - Smyth, TJ AU - Raper, CD AU - Carter, TE AU - Rufty, TW T2 - PHYSIOLOGIA PLANTARUM AB - The role of organic acids in aluminum (Al) tolerance has been the object of intensive research. In the present work, we evaluated the roles of organic acid exudation and concentrations at the root tip on Al tolerance of soybean. Exposing soybean seedlings to Al3+ activities up to 4.7 &mgr;M in solution led to different degrees of restriction of primary root elongation. Al tolerance among genotypes was associated with citrate accumulation and excretion into the external media. Citrate and malate efflux increased in all genotypes during the first 6 h of Al exposure, but only citrate efflux in Al-tolerant genotypes was sustained for an extended period. Tolerance to Al was correlated with the concentration of citrate in root tips of 8 genotypes with a range of Al sensitivities (r2=0.75). The fluorescent stain lumogallion indicated that more Al accumulated in root tips of the Al-sensitive genotype Young than the Al-tolerant genotype PI 416937, suggesting that the sustained release of citrate from roots of the tolerant genotype was involved in Al exclusion. The initial stimulation of citrate and malate excretion and accumulation in the tip of all genotypes suggested the involvement of additional tolerance mechanisms. The experiments included an examination of Al effects on lateral root elongation. Extension of lateral roots was more sensitive to Al than that of tap roots, and lateral root tips accumulated more Al and had lower levels of citrate. DA - 2001/6// PY - 2001/6// DO - 10.1034/j.1399-3054.2001.1120208.x VL - 112 IS - 2 SP - 200-210 SN - 1399-3054 ER - TY - JOUR TI - An evaluation of methods for breaking seed dormancy in kudzu (Pueraria lobata) AU - Susko, DJ AU - Mueller, JP AU - Spears, JF T2 - CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE AB - We evaluated several methods for breaking dormancy in seeds of the invasive weed Pueraria lobata (Willd.) Ohwi (kudzu). Seedlings from untreated seeds emerged from late March to early October 1999 in trays placed outdoors under natural weather conditions; mean cumulative percentage emergence was low (11%). In growth chamber experiments, germination percentages of untreated seeds ranged from 6 to 17%. All hand-scarified seeds germinated, whereas only 6% of intact seeds germinated. Other dormancy-breaking methods that produced higher germination percentages included exposure to ethyl alcohol for 6-12 h (24-86%), exposure to concentrated sulfuric acid for 1-2 h (65-81%), and exposure to moist heat for 5-300 s (30-80%). The influence of temperature on germination percentages of seeds following dry heat treatments depended on the duration of exposure. At 60 and 80°C, germination percentages increased with longer exposures to dry heat and were greatest after 720 min (27 and 60%, respectively). At 100°C, percent germination was greatest when seeds were exposed to dry heat for only 10 min (93%). Cold stratification at 5°C for 0-6 weeks did not increase seed germination percentages after exposure to a range of alternating thermoperiods. Similarly, dry storage at room temperature for 0, 200, or 400 days did not affect germination percentages in light or dark treatments.Key words: Pueraria lobata, physical dormancy, germination, phenology, acid scarification, warm stratification, cold stratification. DA - 2001/2// PY - 2001/2// DO - 10.1139/b00-153 VL - 79 IS - 2 SP - 197-203 SN - 0008-4026 KW - Pueraria lobata KW - physical dormancy KW - germination KW - phenology KW - acid scarification KW - warm stratification KW - cold stratification ER - TY - JOUR TI - Variation among isolates of Fusarium graminearum associated with Fusarium head blight in North Carolina AU - Walker, SL AU - Leath, S AU - Hagler, WM AU - Murphy, JP T2 - PLANT DISEASE AB - Fusarium head blight (FHB) can reduce yield of wheat and decrease the value of harvested grain by accumulation of detrimental toxins. Understanding the variability of the fungal population associated with infection could improve disease control strategies. Sixty-six isolates of Fusarium graminearum associated with FHB were collected in North Carolina and tested for in vitro growth rate, in vitro production of deoxynivalenol (DON) and zearalenone, and pathogenicity on three cultivars of soft red winter wheat. Significant differences among isolates were found for all three traits. Randomly Amplified Polymorphic DNA (RAPD) analysis revealed high levels of genotypic diversity among isolates. Isolates of F. graminearum, F. culmorum, and F. avenaceum acquired from the Pennsylvania State University Fusarium Center were included for comparison in all tests. In vivo levels of DON were measured for the five isolates associated with the highest levels of disease and the five isolates associated with the lowest levels of disease, and no significant differences were found. However, all ten isolates produced detectable levels of DON in vivo. Mean disease ratings ranged from 3.4 to 96.4%, in vitro (DON) levels ranged from 0 to 7176.2 ppm, and zearalenone ranged from 0 to 354.7 ppm, among isolates. A multiple regression model using in vitro growth, in vitro DON, and zearalenone production, collection location, wheat cultivar of isolate origin, plot, tillage conditions, and previous crop as independent variables and percent blighted tissue as the dependent variable was developed. The cumulative R 2 value for the model equaled 0.27 with in vitro rate of growth making the largest contribution. Analysis of phenotype and genotype among isolates demonstrated diversity in a single plot, in a single location, and in North Carolina. Genotypic and phenotypic diversity were significant under both conventional and reduced tillage conditions, and diversity was high regardless of whether the previous crop had been a host or non-host for F. graminearum. These data indicate a variable pathogen population of F. graminearum exists in North Carolina, and members of this population can be both highly pathogenic on wheat and produce high levels of detrimental toxins, indicating a potential threat for problems with FHB within the state. DA - 2001/4// PY - 2001/4// DO - 10.1094/PDIS.2001.85.4.404 VL - 85 IS - 4 SP - 404-410 SN - 0191-2917 KW - resistance ER - TY - JOUR TI - Sequence conservation among fish myostatin orthologues and the characterization of two additional cDNA clones from Morone saxatilis and Morone americana AU - Rodgers, BD AU - Weber, GM T2 - COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY AB - Myostatin (MSTN) negatively regulates mammalian skeletal muscle growth and development by inhibiting myoblast proliferation. Mice and cattle possessing mutant MSTN alleles display a 'double muscling' phenotype characterized by extreme skeletal muscle hypertrophy and/or hyperplasia. MSTN orthologues have been previously characterized in 12 vertebrate species, including the white bass Morone chrysops. Presented herein is the identification and characterization of novel cDNA clones from two additional Morone species: saxatilis (striped bass) and americana (white perch), which were obtained by PCR amplification and subsequent TA-cloning. The predicted amino acid sequence of each cDNA clone contains a putative signal sequence, conserved cysteine residues and a RXXR proteolytic processing site. The different Morone proteins were 97-99% identical to each other and approximately 91, 81, 68 and 67% identical to the tilapia, zebrafish, mammalian and avian proteins, respectively. However, the bioactive domains, which lie downstream of each processing site, were considerably more conserved. They were 99-100% identical within the genus and were approximately 99, 95, 88 and 88% identical to the tilapia, zebrafish, mammalian and avian domains, respectively. This high level of sequence conservation among all known MSTN orthologues suggests that the structure/function relationship of each is equally well conserved among vertebrates. DA - 2001/6// PY - 2001/6// DO - 10.1016/S1096-4959(01)00350-5 VL - 129 IS - 2-3 SP - 597-603 SN - 1879-1107 KW - growth KW - development KW - myostatin KW - GDF-8 KW - skeletal muscle KW - aquaculture KW - Morone ER - TY - JOUR TI - Reducing nitrogen loading to the Gulf of Mexico from the Mississippi River Basin: Strategies to counter a persistent ecological problem AU - Mitsch, WJ AU - Day, JW AU - Gilliam, JW AU - Groffman, PM AU - Hey, DL AU - Randall, GW AU - Wang, NM T2 - BIOSCIENCE DA - 2001/5// PY - 2001/5// DO - 10.1641/0006-3568(2001)051[0373:RNLTTG]2.0.CO;2 VL - 51 IS - 5 SP - 373-388 SN - 1525-3244 ER - TY - JOUR TI - Post-translational regulation of nitrate reductase: mechanism, physiological relevance and environmental triggers AU - Kaiser, WM AU - Huber, SC T2 - JOURNAL OF EXPERIMENTAL BOTANY AB - Assimilatory nitrate reductase (NR) of higher plants is a most interesting enzyme, both from its central function in plant primary metabolism and from the complex regulation of its expression and control of catalytic activity and degradation. Here, present knowledge about the mechanism of post-translational regulation of NR is summarized and the properties of the regulatory enzymes involved (protein kinases, protein phosphatases and 14-3-3-binding proteins) are described. It is shown that light and oxygen availability are the major external triggers for the rapid and reversible modulation of NR activity, and that sugars and/or sugar phosphates are the internal signals which regulate the protein kinase(s) and phosphatase. It is also demonstrated that stress factors like nitrate deficiency and salinity have remarkably little direct influence on the NR activation state. Further, changes in NR activity measured in vitro are not always associated with changes in nitrate reduction rates in vivo, suggesting that NR can be under strong substrate limitation. The degradation and half-life of the NR protein also appear to be affected by NR phosphorylation and 14-3-3 binding, as NR activation always correlates positively with its stability. However, it is not known whether the molecular form of NR in vivo affects its susceptibility to proteolytic degradation, or whether factors that affect the NR activation state also independently affect the activity or induction of the NR protease(s). A second and potentially important function of NR, the production of nitric oxide (NO) from nitrite is briefly described, but it remains to be determined whether NR produces NO for pathogen/stress signalling in vivo. DA - 2001/10// PY - 2001/10// DO - 10.1093/jexbot/52.363.1981 VL - 52 IS - 363 SP - 1981-1989 SN - 0022-0957 KW - nitrate reductase KW - nitrite KW - nitric oxide KW - regulation KW - protein phosphorylation KW - 14-3-3-binding KW - signalling KW - sugars ER - TY - JOUR TI - Peanut response to prohexadione calcium in three seeding rate-row pattern planting systems AU - Jordan, DL AU - Beam, JB AU - Johnson, PD AU - Spears, JF T2 - AGRONOMY JOURNAL AB - Peanut ( Arachis hypogaea L.) in the USA is generally grown in single rows spaced 91 to 102 cm apart. Research suggests that pod yield can be increased by growing peanut in twin rows (18–23 cm spacing) on beds spaced 91 to 102 cm apart. Prohexadione Ca (Ca salt of 3,5‐dioxo‐4‐propionylcyclohexanecarboxylic acid) increases row visibility and in some instances increases pod yield and improves market grade factors. Research was conducted to determine response of peanut grown in three seeding rate–row pattern planting systems (single rows at a seeding rate of 120 kg ha −1 or twin rows spaced 18 cm apart on beds spaced 91 cm apart at seeding rates of 145 and 190 kg ha −1 ) to prohexadione Ca applied at 50% row closure. Row visibility increased and main stem height was shorter at the end of the season when prohexadione Ca was applied in most environments and for most seeding rate–row pattern combinations when compared with nontreated peanut. Pod yield and gross economic value increased 160 kg ha −1 and $96 ha −1 , respectively, when prohexadione Ca was applied irrespective of the seeding rate–row pattern combination or environment. Prohexadione Ca also increased the percentage of extra large kernels (% ELK) but did not affect percentages of sound mature kernels (SMK), other kernels (OK), sound splits (SS), or total sound mature kernels (TSMK). Seeding rate–row pattern combination affected pod yield, market grade, and gross economic value although a consistent trend was not apparent. DA - 2001/// PY - 2001/// DO - 10.2134/agronj2001.931232x VL - 93 IS - 1 SP - 232-236 SN - 0002-1962 ER - TY - JOUR TI - Parity violation in compound nuclei: experimental methods and recent results AU - Mitchell, GE AU - Bowman, JD AU - Penttila, SI AU - Sharapov, EI T2 - PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS AB - The TRIPLE Collaboration studies of space-parity symmetry in the compound nucleus show numerous examples of parity violation in Br, Rh, Pd, Ag, Cd, In, Sn, Sb, I, Cs, Xe, La, U, and Th. The longitudinal cross section asymmetries have measured values in the range of 10−3–10−1 for neutron energies from several eV up to 300–2000eV, depending on the target. The high density of states leads to enhancement of the parity violation by factors as large as 106 relative to parity violation in pp scattering. The high degree of complexity of the levels permits the use of statistical methods for determination of the root mean square weak matrix element M for each nucleus. This report is focused on the experimental results of the TRIPLE Collaboration studies. Parity violation has been observed in 75 resonances of 18 nuclides. The experimental data and analysis are presented for each nuclide studied. A nonstatistical anomaly (the sign correlation effect) was observed in thorium. Statistical analysis techniques were developed and successfully applied to determine the rms weak matrix elements and the weak spreading widths Γw. The value of Γw obtained from our analysis is about 1.8×10−7eV, which is in qualitative agreement with theoretical expectations. The individual weak spreading widths are consistent with a constant or slowly varying mass dependence and there is evidence for local fluctuations. DA - 2001/11// PY - 2001/11// DO - 10.1016/S0370-1573(01)00016-3 VL - 354 IS - 3 SP - 157-241 SN - 1873-6270 KW - parity violation KW - weak interaction KW - compound states KW - neutron resonances KW - nuclear spectroscopy KW - polarized-neutron beam KW - rms matrix element KW - spreading width KW - statistical theory ER - TY - JOUR TI - Optimizing nitrogen application timing in no-till soft red winter wheat AU - Weisz, R AU - Crozier, CR AU - Heiniger, RW T2 - AGRONOMY JOURNAL AB - As no‐till acreage increases, N management guidelines need re‐examination due to the potential effects of surface residue on N transformations and crop development. Our objectives were to determine: (i) if N applied at Zadok's Growth Stage (GS) 25 improves grain yield of no‐till winter wheat ( Triticum aestivum L.), (ii) if any yield increase was the result of increased spring tillering, and (iii) if there is a critical tiller density above which N application at GS‐25 in no‐till wheat was not required. Research was conducted at three sites in North Carolina with seven site‐years between fall 1996 and spring 1999. A continuum of GS‐25 tiller densities was generated (161‐1774 tillers m −2 ) by planting at different seeding rates and dates in a randomized complete block design. Five N treatments were applied at GS‐25, and three were applied at GS‐30. Tillering response to early spring N, yield, and yield components were measured. increasing early spring N rates resulted in higher tiller densities at GS‐30, and GS‐25 tiller density was a significant covariate. With GS‐25 tiller densities >550 tillers m −2 , yields were higher when all N was applied at GS‐30. In years without spring freezes, wheat with <550 tillers m −2 achieved optimum yields when spring N was applied at GS‐25. Manipulating the timing of spring N application can optimize early spring tillering and yield component formation. DA - 2001/// PY - 2001/// DO - 10.2134/agronj2001.932435x VL - 93 IS - 2 SP - 435-442 SN - 0002-1962 ER - TY - JOUR TI - Nonphytotoxic aluminum-peat complexes suppress Phytophthora parasitica AU - Fichtner, EJ AU - Hesterberg, DL AU - Shew, HD T2 - PHYTOPATHOLOGY AB - ABSTRACT Amendment of peat-based potting media with Al(2)(SO(4))(3) suppresses damping-off of Vinca (Catharanthus roseus) caused by Phytophthora parasitica. The species of aluminum (Al) responsible for disease suppression have not been identified. The objective of this study was to determine the effects of amount and pH of Al(2)(SO(4))(3) amendment solutions on survival of P. parasitica. In separate experiments, peat was amended with Al(2)(SO(4))(3) solutions adjusted to pH 4 or 6 at either 0.0158 or 0.0079 g of Al per gram of peat. Amended peat was placed in Büchner funnels maintained at -2.5 kPa matric potential. Peat was infested with P. parasitica by placing zero, two, or five colonized Vinca leaf disks in each funnel, and 15 Vinca seeds were placed in each funnel. After 24 h, the matric potential was brought to 0 kPa to induce zoospore release and returned to -2.5 kPa after 24 h. Pathogen populations and stand counts were assessed after 2-week incubation. Al amendment solutions at both pH 4 and 6 reduced pathogen populations at 0.0158 g of Al per gram of peat. Solutions at pH 4 reduced pathogen populations by more than 90% at both inoculum levels; amendment solutions at pH 6 reduced populations by 95% at the low inoculum level and 65% at the high inoculum level. The prevalence of Al(OH)(2)(+) in peat amended with Al(2)(SO(4))(3) solution at pH 6 suggests that ions other than Al(3+) may be responsible for pathogen suppression. Based on the difference in chemical conditions of Al-amended peat and suppressive mineral soils, the mechanism of Al-mediated suppression of plant pathogens is speculated to be different in the two systems. Peat containing Al-peat complexes was chemically suppressive to P. parasitica and may confer Al-mediated suppression of plant pathogens with a nonphytotoxic form of Al. DA - 2001/11// PY - 2001/11// DO - 10.1094/PHYTO.2001.91.11.1092 VL - 91 IS - 11 SP - 1092-1097 SN - 1943-7684 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035156475&partnerID=MN8TOARS ER - TY - JOUR TI - Isolation and characterization of myostatin complementary deoxyribonucleic acid clones from two commercially important fish: Oreochromis mossambicus and Morone chrysops AU - Rodgers, BD AU - Weber, GM AU - Sullivan, CV AU - Levine, MA T2 - ENDOCRINOLOGY AB - In mammals, skeletal muscle mass is negatively regulated by a muscle-derived growth/differentiating factor named myostatin (MSTN) that belongs to the transforming growth factor-β superfamily. Although putative MSTN homologs have been identified from several vertebrates, nonmammalian orthologs remained poorly defined. Thus, we isolated and characterized MSTN complementary DNA clones from the skeletal muscle of the tilapia Oreochromis mossambicus and the white bass Morone chrysops. The nucleic and amino acid sequences from both fish species are highly homologous to the previously identified mammalian and avian orthologs, and both possess conserved cysteine residues and putative RXXR proteolytic processing sites that are common to all transforming growth factor-β family members. Western blotting of conditioned medium from human embryonal kidney (HEK293) cells overexpressing a His-tagged tilapia MSTN indicates that the secreted fish protein is processed in a manner similar to mouse MSTN. However, in contrast to mice, MSTN expression in tilapia is not limited to skeletal muscle as it occurs in many tissues. Furthermore, the timing of MSTN expression in developing tilapia larvae coincides with myogenesis. These results suggest that the biological actions of MSTN in the tilapia and possibly in other fishes may not be limited to myocyte growth repression, but may additionally influence different cell types and organ systems. DA - 2001/4// PY - 2001/4// DO - 10.1210/en.142.4.1412 VL - 142 IS - 4 SP - 1412-1418 SN - 0013-7227 ER - TY - JOUR TI - In vitro hormone induction of final oocyte maturation in striped bass (Morone saxatilis) follicles is inhibited by blockers of phosphatidylinositol 3-kinase activity AU - Weber, GM AU - Sullivan, CV T2 - COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY AB - Oocyte germinal vesicle breakdown (GVBD) was induced in striped bass ovarian fragments when tissues were incubated with 100-nM recombinant human insulin-like growth factor-I (rhIGF-I), 25-IU human chorionic gonadotropin (hCG) ml−1, or 290 nM of the maturation-inducing steroid (MIS), 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S). Inhibitors of phosphatidylinositol 3-kinase (PI 3-K), wortmannin (100 nM) and LY 294002 (50 μM), inhibited GVBD induced by these hormones. Furthermore, the inhibitors attenuated hCG-induced steroid hormone synthesis. Previous studies report that gap junction uncouplers inhibit GVBD induced by hCG, but not by rhIGF-I, in striped bass. We show that 20β-S-induced GVBD is also attenuated by 1 mM 1-heptanol or 1-octanol without being affected by incubation with 3 mM ethanol. Thus, the effects of inhibiting PI 3-K activity on GtH and MIS actions are similar to effects of uncoupling gap junctions. These data suggest that PI 3-K activity is required for GtH- MIS- and IGF-I induction of GVBD in striped bass. Our data are also consistent with the notion that a ligand that regulates PI 3-K activity, possibly an IGF, participates in maintenance of gap junctional communication required for maximal GtH and MIS action. DA - 2001/6// PY - 2001/6// DO - 10.1016/S1096-4959(01)00349-9 VL - 129 IS - 2-3 SP - 467-473 SN - 1096-4959 KW - gap junction KW - gonadotropin KW - insulin-like growth factor KW - maturation inducing steroid KW - meiosis KW - oocyte development KW - phosphatidylinositol 3-kinase KW - signal transduction KW - Wortmannin KW - LY 294002 ER - TY - JOUR TI - Effect of various dairy packaging materials on the headspace analysis of ultrapasteurized milk AU - Simon, M AU - Hansen, AP AU - Young, CT T2 - JOURNAL OF DAIRY SCIENCE AB - Milk from three different dairies (each a separate trial: 1, 2, and 3) was standardized to 2% fat and processed at 140.6, 129.4, 118.3, and 107.2 degrees C (temperatures 1, 2, 3, and 4, respectively) for 2 s and packaged into six different packaging boards [standard (A) milk boards with standard seam, juice boards with standard (B) and J- bottom (D) seams, barrier boards with standard (C) and J-bottom (E) seams, and foil (F) boards with J-bottom seam] resulting in 24 different treatments. A Shimadzu 15A series chromatograph equipped with a Porapak-P column was used to measure the headspace of the milk stored at 6.7 degrees C for 1, 2, 3, 5, 10, and 15 wk of storage. Gas chromatographic headspace analysis for sulfur compounds showed that hydrogen sulfide, methanethiol, and dimethyl sulfide were detected in milk processed at 140.6, 129.4, 118.3, and 107.2 degrees C. In addition, dimethyl disulfide was detected in milk processed at 140.6 and 129.4 degrees C, and dimethyl trisulfide was detected at 140.6 degrees C. Milk processed at 140.6 degrees C contained the most sulfur compounds. Samples C1, E1, and F1 retained the most hydrogen sulfide and methanethiol at 6 d of storage. Methanethiol appeared to be heat-induced. At wk 6, a slightly hammy or cardboardy flavor was detected for milk packaged in boards with standard seams (A, B, and C), and a slightly cooked flavor was detected for milk packaged in barrier and foil boards with J-bottom (E and F) seams. The hammy or cardboardy flavor intensified with storage time, and all of the cooked flavor dissipated at wk 10. DA - 2001/4// PY - 2001/4// DO - 10.3168/jds.S0022-0302(01)74533-X VL - 84 IS - 4 SP - 774-783 SN - 0022-0302 KW - ultrapasteurized milk KW - packaging materials KW - headspace analysis ER - TY - JOUR TI - Altered aluminum inhibition of soybean root elongation in the presence of magnesium AU - Silva, I. R. AU - Smyth, T. J. AU - Israel, D. W. AU - Rufty, T. W. T2 - Plant and Soil DA - 2001/// PY - 2001/// DO - 10.1023/A:1010384516517 VL - 230 IS - 2 SP - 223-230 ER - TY - JOUR TI - A linkage map of hexaploid oat based on grass anchor DNA clones and its relationship to other oat maps AU - Portyanko, VA AU - Hoffman, DL AU - Lee, M AU - Holland, JB T2 - GENOME AB - A cultivated oat linkage map was developed using a recombinant inbred population of 136 F6:7 lines from the cross 'Ogle' × 'TAM O-301'. A total of 441 marker loci, including 355 restriction fragment length polymorphism (RFLP) markers, 40 amplified fragment length polymorphisms (AFLPs), 22 random amplified polymorphic DNAs (RAPDs), 7 sequence-tagged sites (STSs), 1 simple sequence repeat (SSR), 12 isozyme loci, and 4 discrete morphological traits, was mapped. Fifteen loci remained unlinked, and 426 loci produced 34 linkage groups (with 2–43 loci each) spanning 2049 cM of the oat genome (from 4.2 to 174.0 cM per group). Comparisons with other Avena maps revealed 35 genome regions syntenic between hexaploid maps and 16–34 regions conserved between diploid and hexaploid maps. Those portions of hexaploid oat maps that could be compared were completely conserved. Considerable conservation of diploid genome regions on the hexaploid map also was observed (89–95%); however, at the whole-chromosome level, colinearity was much lower. Comparisons among linkage groups, both within and among Avena mapping populations, revealed several putative homoeologous linkage group sets as well as some linkage groups composed of segments from different homoeologous groups. The relationships between many Avena linkage groups remain uncertain, however, due to incomplete coverage by comparative markers and to complications introduced by genomic duplications and rearrangements.Key words: Avena, linkage map, comparative mapping, homoeology. DA - 2001/4// PY - 2001/4// DO - 10.1139/gen-44-2-249 VL - 44 IS - 2 SP - 249-265 SN - 0831-2796 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035055426&partnerID=MN8TOARS KW - Avena KW - linkage map KW - comparative mapping KW - homoeology ER - TY - JOUR TI - The role of cell differentiation state and HMG-I/Y in the expression of transgenes flanked by matrix attachment regions AU - Ascenzi, R AU - Ingram, JL AU - Massel, M AU - Thompson, WF AU - Spiker, S AU - Weissinger, AK T2 - TRANSGENIC RESEARCH DA - 2001/// PY - 2001/// DO - 10.1023/A:1012082602587 VL - 10 IS - 5 SP - 465-470 SN - 0962-8819 KW - cell differentiation and proliferation KW - chromatin KW - matrix KW - scaffold attachment region (MAR/SAR) KW - plant high mobility group-I/Y protein (HMG-I/Y) KW - transgene expression KW - tobacco ER - TY - JOUR TI - Phosphorylation of synthetic peptides by a CDPK and plant SNF1-related protein kinase. Influence of proline and basic amino acid residues at selected positions AU - Huang, JZ AU - Huber, SC T2 - PLANT AND CELL PHYSIOLOGY AB - Spinach (Spinacia oleracea L.) leaf sucrose-phosphate synthase (SPS) can be inactivated by phosphorylation of Ser-158 by calmodulin-like domain protein kinases (CDPKs) or SNF1-related protein kinases (SnRK1) in vitro. While the phosphorylation site sequence is relatively conserved, most of the deduced sequences of SPS from dicot species surrounding the Ser-158 regulatory phosphorylation site contain a Pro residue at P–4 (where P is the phosphorylated Ser); spinach is the exception and contains an Arg at P–4. We show that a Pro at P–4 selectively inhibits phosphorylation of the peptide by a CDPK relative to a SnRK1. The presence of a Pro at P–4, by allowing a tight turn in the peptide substrate, may interfere with proper binding of residues at P–5 and beyond. Both kinases had greater activity with peptides having basic residues at P–6 and P+5 (in addition to the known requirement for an Arg at P–3/P–4), and when the residue at P–6 was a His, the pH optimum for phosphorylation of the peptide was acid shifted. The results are used to predict proteins that may be selectively phosphorylated by SnRK1s (as opposed to CDPKs), such as SPS in dicot species, or may be phosphorylated in a pH-dependent manner. DA - 2001/10// PY - 2001/10// DO - 10.1093/pcp/pce137 VL - 42 IS - 10 SP - 1079-1087 SN - 0032-0781 KW - CDPKs KW - phosphorylation motif KW - protein kinase specificity KW - SNF1-related protein kinase KW - Spinacia oleracea ER - TY - JOUR TI - Nitrogen leaching in sand-based rootzones amended with inorganic soil amendments and sphagnum peat AU - Bigelow, C. A. AU - Bowman, D. C. AU - Cassel, D. K. T2 - Journal of the American Society for Horticultural Science DA - 2001/// PY - 2001/// VL - 126 IS - 1 SP - 151-156 ER - TY - JOUR TI - Creeping bentgrass response to inorganic soil amendments and mechanically induced subsurface drainage and aeration AU - Bigelow, CA AU - Bowman, DC AU - Cassel, DK AU - Rufty, TW T2 - CROP SCIENCE AB - Creeping bentgrass ( Agrostis stolonifera var. palustris Huds. Farw.) golf greens often decline under the hot, humid summer conditions of the southeastern USA. Factors associated with this decline may be poor soil aeration, excessive soil wetness, high temperatures, and turfgrass diseases. A field study evaluated a mechanical forced air system for its ability to modify the soil water content and oxygen (O 2 ) status of newly constructed sand‐based rootzones, and its effects on turfgrass quality (TQ) and seasonal bentgrass rooting. Three drainage situations were studied: gravity drainage (control treatment) and gravity drainage supplemented by two mechanically induced drainage treatments, water evacuation (WE) or WE followed by air‐injection (AI). In addition, the effects of peat moss and several inorganic soil amendments on bentgrass establishment and growth were studied. Compared with gravity drainage, WE significantly decreased water contents (0.01–0.05 m 3 m −3 ) averaged across the 0‐ to 27‐cm depth, with the greatest change occurring near the bottom of the rooting media. Seasonal fluctuations in soil O 2 and CO 2 concentrations were observed, but O 2 remained high, 0.19 m 3 m −3 , and CO 2 was low, <0.01 m 3 m −3 , regardless of drainage treatment. Drainage treatments had no effect on TQ or root mass density (RMD). However, both TQ and RMD increased from 1998 to 1999, possibly becaue of greater turfgrass density. Amendments had significant effects on establishment and TQ in the following order: peat moss > Ecolite = Profile > Greenschoice ≥ unamended sand. This response was probably due to improved water and nutrient retention of the amended rootzones. Although the forced air–vacuum technology provided little benefit in these newly constructed greens, it may be useful on mature putting greens that suffer from poor soil aeration or drainage. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.413797x VL - 41 IS - 3 SP - 797-805 SN - 0011-183X ER - TY - JOUR TI - Ambient ozone and plant health AU - Krupa, S AU - McGrath, MT AU - Andersen, CP AU - Booker, FL AU - Burkey, KO AU - Chappelka, AH AU - Chevone, BI AU - Pell, EJ AU - Zilinskas, BA T2 - PLANT DISEASE AB - HomePlant DiseaseVol. 85, No. 1Ambient Ozone and Plant Health PreviousNext OPENOpen Access licenseAmbient Ozone and Plant HealthSagar Krupa, Margaret Tuttle McGrath, Christian P. Andersen, Fitzgerald L. Booker, Kent O. Burkey, Arthur H. Chappelka, Boris I. Chevone, Eva J. Pell, and Barbara A. ZilinskasSagar KrupaSearch for more papers by this author, Margaret Tuttle McGrathSearch for more papers by this author, Christian P. AndersenSearch for more papers by this author, Fitzgerald L. BookerSearch for more papers by this author, Kent O. BurkeySearch for more papers by this author, Arthur H. ChappelkaSearch for more papers by this author, Boris I. ChevoneSearch for more papers by this author, Eva J. PellSearch for more papers by this author, and Barbara A. ZilinskasSearch for more papers by this authorAffiliationsAuthors and Affiliations Sagar Krupa , University of Minnesota, St. Paul Margaret Tuttle McGrath , Cornell University, Riverhead, NY Christian P. Andersen , U.S. Environmental Protection Agency, Corvallis, OR Fitzgerald L. Booker Kent O. Burkey , USDA-ARS Air Quality Research Unit, North Carolina State University, Raleigh Arthur H. Chappelka , Auburn University, Auburn, AL Boris I. Chevone , Virginia Polytechnic Institute & State University, Blacksburg Eva J. Pell , Pennsylvania State University, University Park Barbara A. Zilinskas , Rutgers University, New Brunswick, NJ Published Online:23 Feb 2007https://doi.org/10.1094/PDIS.2001.85.1.4AboutSectionsPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat DetailsFiguresLiterature CitedRelated Vol. 85, No. 1 January 2001SubscribeISSN:0191-2917e-ISSN:1943-7692 Metrics Article History Issue Date: 25 Jan 2008Published: 23 Feb 2007 Pages: 4-12 Information© 2000 The American Phytopathological SocietyPDF downloadCited byAcute ozone exposure decreases terpene emissions from Canary Island pinesAgricultural and Forest Meteorology, Vol. 333Physiological status of House Sparrows (Passer domesticus) along an ozone pollution gradient21 February 2023 | Ecotoxicology, Vol. 32, No. 2Impacts of Agricultural Soil NO x Emissions on O 3 Over Mainland China11 February 2023 | Journal of Geophysical Research: Atmospheres, Vol. 128, No. 4Improvement of local ozone phytotoxicity modelling for autochthonous grape 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Scarlett) Grown at Elevated Ozone and Carbon Dioxide ConcentrationsPlant Biology, Vol. 7, No. 6Role of ethylene diurea (EDU) in assessing impact of ozone on Vigna radiata L. plants in a suburban area of Allahabad (India)Chemosphere, Vol. 61, No. 2Air pollution, precipitation chemistry and forest health in the Retezat Mountains, Southern Carpathians, RomaniaEnvironmental Pollution, Vol. 137, No. 3Assessment of Ambient Ozone Effects on Vegetation Using Snap Bean as a Bioindicator Species1 May 2005 | Journal of Environmental Quality, Vol. 34, No. 3Gesunde Pflanzen unter zuk�nftigem Klima14 December 2004 | Gesunde Pflanzen, Vol. 57, No. 1ENVIRONMENTAL FACTORS THAT CAUSE PLANT DISEASESA chamberless field exposure system for ozone enrichment of short vegetationEnvironmental Pollution, Vol. 133, No. 1Elevated CO2 protects poplar (Populus trichocarpa × P. deltoides) from damage induced by O3: identification of mechanismsFunctional Plant Biology, Vol. 32, No. 3Effects of ozone on the foliar histology of the mastic plant (Pistacia lentiscus L.)Environmental Pollution, Vol. 132, No. 2Aphid individual performance may not predict population responses to elevated CO 2 or O 35 July 2004 | Global Change Biology, Vol. 10, No. 8Responses of hybrid poplar clones and red maple seedlings to ambient O3 under differing light within a mixed hardwood forestEnvironmental Pollution, Vol. 130, No. 2Ecophysiological and biochemical strategies of response to ozone in Mediterranean evergreen broadleaf speciesAtmospheric Environment, Vol. 38, No. 15Ambient flux-based critical values of ozone for protecting vegetation: differing spatial scales and uncertainties in risk assessmentAtmospheric Environment, Vol. 38, No. 15Ozone impacts on cotton: towards an integrated mechanismEnvironmental Pollution, Vol. 126, No. 3Field crop responses to ultraviolet-B radiation: a reviewAgricultural and Forest Meteorology, Vol. 120, No. 1-4Sensitivity of Watermelon Cultigens to Ambient Ozone in North CarolinaGerald J. Holmes and Jonathan R. Schultheis23 February 2007 | Plant Disease, Vol. 87, No. 4Ozone: A Novel Plant “Pathogen”Factors that affect leaf extracellular ascorbic acid content and redox status20 December 2002 | Physiologia Plantarum, Vol. 117, No. 1The impact of ozone on a salt marsh cordgrass (Spartina alterniflora)Environmental Pollution, Vol. 120, No. 3 DA - 2001/1// PY - 2001/1// DO - 10.1094/PDIS.2001.85.1.4 VL - 85 IS - 1 SP - 4-12 SN - 0191-2917 ER - TY - JOUR TI - Preference by sheep and goats among hay of eight tall fescue cultivars AU - Burns, J. C. AU - Fisher, D. S. AU - Mayland, H. F. T2 - Journal of Animal Science AB - Grazing ruminants use both visual cues and taste in selecting their diet. Preference during grazing may not be the same when forage is dried for hay and cut into lengths prior to feeding in confinement. Eight cultivars of tall fescue (Festuca arundinacea Schreb.), previously evaluated for preference while grazed, were harvested three times over a period of 2 yr. The hays were air-dried, baled, and passed through a hydraulic bale processor prior to feeding. Five experiments were conducted. All three harvests were evaluated with sheep and the last two also with goats, using six animals each time. During an adaptation phase, hays were offered alone as meals. In the experimental phase, every possible pair of hays (28 pairs) was presented for a meal. Data were analyzed by multidimensional scaling and by traditional analyses. Preference was significant among cultivars in all experiments. Multidimensional scaling showed that selection was based on two criteria with two dimensions being significant. Sheep preferred KENHY followed by KENTUCKY 31 and STARGRAZER but preferenced against BARCEL. HIMAG, MO-96, and C1 were intermediate and MOZARK was variable. Goats were similar to sheep in preferring KENHY followed by STARGRAZER and selected against MOZARK and BARCEL. KENTUCKY 31, HIMAG, MO-96, and C1 were intermediate. In all five experiments, the general association was positive for available carbohydrate fractions and negative for fiber fractions that contribute to cell wall rigidity. DA - 2001/// PY - 2001/// DO - 10.2527/2001.791213x VL - 79 IS - 1 SP - 213-224 ER - TY - JOUR TI - Atmospheric carbon dioxide, irrigation, and fertilization effects on phenolic and nitrogen concentrations in loblolly pine (Pinus taeda) needles AU - Booker, FL AU - Maier, CA T2 - TREE PHYSIOLOGY AB - Concentrations of total soluble phenolics, catechin, proanthocyanidins (PA), lignin and nitrogen (N) were measured in loblolly pine (Pinus taeda L.) needles exposed to either ambient CO(2) concentration ([CO(2)]), ambient plus 175 or ambient plus 350 micromol CO(2) mol(-1) in branch chambers for 2 years. The CO(2) treatments were superimposed on a 2 x 2 factorial combination of irrigation and fertilization treatments. In addition, we compared the effects of branch chambers and open-top chambers on needle chemistry. Proanthocyanidin and N concentrations were measured in needles from branch chambers and from trees in open-top chambers exposed concurrently for two years to either ambient [CO(2)] or ambient plus 200 micromol CO(2) mol(-1) in combination with a fertilization treatment. In the branch chambers, concentrations of total soluble phenolics in needles generally increased with needle age. Concentrations of total soluble phenolics, catechin and PA in needle extracts increased about 11% in response to the elevated [CO(2)] treatments. There were no significant treatment effects on foliar lignin concentrations. Nitrogen concentrations were about 10% lower in needles from the elevated [CO(2)] treatments than in needles from the ambient [CO(2)] treatments. Soluble phenolic and PA concentrations were higher in the control and irrigated soil treatments in about half of the comparisons; otherwise, differences were not statistically significant. Needle N concentrations increased 23% in response to fertilization. Treatment effects on PA and N concentrations were similar between branch and open-top chambers, although in this part of the study N concentrations were not significantly affected by the CO(2) treatments in either the branch or open-top chambers. We conclude that elevated [CO(2)] and low N availability affected foliar chemical composition, which could in turn affect plant-pathogen interactions, decomposition rates and mineral nutrient cycling. DA - 2001/6// PY - 2001/6// DO - 10.1093/treephys/21.9.609 VL - 21 IS - 9 SP - 609-616 SN - 1758-4469 KW - catechin KW - CO2 enrichment KW - lignin KW - nutrition KW - proanthocyanidins KW - secondary compounds KW - tannins ER - TY - JOUR TI - Leaf pigment and canopy photosynthetic response to early flower removal in cotton AU - Wells, R T2 - CROP SCIENCE AB - Loss of reproductive organs from cotton ( Gossypium hirsutum L.) often results in compensatory growth that culminates in altered morphologic, physiologic, and photosynthetic patterns. This field study examined the change in leaf chlorophyll (Chl) and anthocyanin (Ant) contents and their relationship to canopy photosynthetic patterns in response to the removal of flowers for the first 2 wk of flowering. Flower removal caused an extended flowering period in all years except 1995 when temperatures were highest. The largest yield differences occurred in 1994, while there were no significant differences in any other year. Differences in canopy photosynthesis occurred on at least one date in each year that measurements were made. In 1997, significant differences were observed on four dates and plants from the removal treatment had 15% larger area under the seasonal photosynthetic curve. Chlorophyll concentrations were higher in leaves from the flower removal treatment after 100 d after planting. Anthocyanin levels were higher in controls during the same period, indicating significant negative relationships between Ant levels and either Chl a/b ratio or Chl concentration. Pigment differences late in plant ontogeny appeared to be associated with delayed senescence of plants from the removal treatment. While pigment levels late in development were associated with canopy photosynthesis, not all treatment differences could be related to Chl loss. In 2 yr, significant differences in canopy photosynthesis occurred prior to differences in Chl concentration, implicating other morphological and physiological adaptations in response to early fruit loss. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4151522x VL - 41 IS - 5 SP - 1522-1529 SN - 1435-0653 ER - TY - JOUR TI - Common ragweed interference in peanut AU - Clewis, SB AU - Askew, SD AU - Wilcut, JW T2 - WEED SCIENCE AB - Studies were conducted to evaluate density-dependent effects of common ragweed on weed growth and peanut growth and yield. Common ragweed height was not affected by weed density and peanut canopy diameter. Weed height exceeded peanut height throughout the growing season, indicating that competition for light occurred between the two species. Common ragweed aboveground dry biomass per plant decreased as weed density increased, but total weed dry biomass per meter of crop row increased with weed density. The rectangular hyperbola model described the effect of weed density on percent peanut yield loss. With the asymptote constrained to 100% maximum yield loss, the I coefficient (yield loss per unit density as density approaches zero) was 68.3 ± 12.2%. Common ragweed did not influence the occurrence of tomato spotted wilt virus, early leaf spot (Cercospora arachidicola), southern stem rot (Sclerotium rolfsii), and Cylindrocladium black rot (Cylindrocladium crotalariae). However, as common ragweed density increased, the incidence of late leaf spot (Cercosporidium personatum) increased. Results indicate that common ragweed is one of the more competitive weeds in peanut and a potential economic threat to peanut growers. DA - 2001/// PY - 2001/// DO - 10.1614/0043-1745(2001)049[0768:CRIIP]2.0.CO;2 VL - 49 IS - 6 SP - 768-772 SN - 0043-1745 KW - common ragweed, Ambrosia artemisiifolia L. AMBEL KW - peanut, Arachis hypogaea L. 'NC 7' KW - competition KW - economic thresholds KW - models KW - peanut diameter KW - peanut diseases KW - weed biomass KW - weed density KW - weed height ER - TY - JOUR TI - Antibacterial activity of the herbicide glufosinate on Pseudomonas syringae pathovar glycinea AU - Pline, WA AU - Lacy, GH AU - Stromberg, V AU - Hatzios, KK T2 - PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY AB - The antibacterial activity of the herbicide glufosinate on Pseudomonas syringae pathovar (pv.) glycinea (L-529), causal agent of soybean blight, was examined in culture and in planta. Bacteria were grown in medium containing either formulated or technical-grade glufosinate from 0.01 to 100 mM, and growth was monitored by turbidity measurements over time. Glufosinate inhibited bacterial growth at concentrations of 1 mM or greater and delayed growth at concentrations as low as 0.01 mM. Metabolism of [14C]glufosinate by P. syringae pv. glycinea grown in Davis minimal medium containing either a sublethal (1 mM) or a lethal (100 mM) glufosinate concentration was measured incrementally up to 45 h after inoculation. Thin-layer chromatography analysis revealed the presence of three glufosinate metabolites in addition to the parent compound. The rate of [14C]glufosinate metabolism by bacteria was greater in medium treated with 1 mM than in medium treated with 100 mM glufosinate. More 14C was recovered as 3-methylphosphinico-propionic acid and as an unidentified metabolite with an Rf value of 0.45 in medium treated with 1 mM than in medium treated with 100 mM glufosinate. These data suggest that P. syringae pv. glycinea can slowly metabolize glufosinate into less toxic metabolites, resulting in greater bacterial growth in medium treated with 1 mM glufosinate. Treatment of transgenic glufosinate-resistant (GR) soybeans with field rates of glufosinate reduced the number of live P. syringae pv. glycinea at 90 h after inoculation. Inoculated GR soybeans showed a 45;pc reduction of colony forming units after treatment with 0.5 kg/ha glufosinate and a 60;pc reduction after treatment with 1.0 kg/ha glufosinate. These results show that glufosinate exhibits some antibacterial activity against P. syringae pv. glycinea, but at concentrations greater than those of registered bactericides. DA - 2001/9// PY - 2001/9// DO - 10.1006/pest.2001.2556 VL - 71 IS - 1 SP - 48-55 SN - 1095-9939 KW - glufosinate KW - transgenic soybeans KW - glufosinate-resistant soybeans KW - herbicide metabolism KW - soybean blight KW - antibacterial activity of herbicides ER - TY - JOUR TI - Selection for greater beta-glucan content in oat grain AU - Cervantes-Martinez, CT AU - Frey, KJ AU - White, PJ AU - Wesenberg, DM AU - Holland, JB T2 - CROP SCIENCE AB - Oat ( Avena sativa L.) β‐glucan lowers serum cholesterol in humans. Development of oat cultivars with greater groat (caryopsis) β‐glucan content would increase the nutritional and economic value of the crop. The objectives of this experiment were to evaluate the response to phenotypic selection among individual S 0 plants for greater groat β‐glucan content in two genetically broad‐based populations; to compare selected experimental lines to standard check cultivars; and to estimate genetic variances and heritabilities and to test for nonadditive genetic variance for β‐glucan content. We measured groat β‐glucan contents of check cultivars and parental lines and random S 0:1 lines from initial and selected generations of each population grown in field experiments in 1996 and 1997 at two Iowa locations. Mean β‐glucan content increased from 53.9 to 59.9 g kg −1 in one population, and from 63.5 to 66.0 g kg −1 in the other, following selection. Genetic variance of β‐glucan content decreased by 9 to 22% following selection, but heritability for β‐glucan content did not change significantly. Heritability estimates ranged from 0.80 to 0.85 on a line mean basis. Additive variance was the only substantial component of genetic variance. Some experimental lines had significantly greater β‐glucan content than the best check cultivars and lines. Phenotypic selection for greater groat β‐glucan content will be effective for developing cultivars with elevated β‐glucan contents. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.4141085x VL - 41 IS - 4 SP - 1085-1091 SN - 0011-183X UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034890343&partnerID=MN8TOARS ER - TY - JOUR TI - Removal of perennial ryegrass from overseeded bermudagrass using cultural methods AU - Horgan, BP AU - Yelverton, FH T2 - CROP SCIENCE AB - Turfgrass managers in the southeastern United States often overseed ‘Tifway’ bermudagrass [ Cynodon transvaalensis Burtt‐Davey × C. dactylon (L.) Pers.] with perennial ryegrass ( Lolium perenne L.) to provide a dense green turf during winter months. Although overseeding provides benefits, the spring transition from perennial ryegrass to bermudagrass can be troublesome and inconsistent. Perennial ryegrass may survive longer into the spring than is desired due to cool, wet conditions. The following experiment evaluated cultural methods for removal of perennial ryegrass from overseeded bermudagrass in the spring and early summer. The experiment was conducted at the North Carolina State University Turfgrass Field Center in Raleigh in the 1995 to 1996 and 1996 to 1997 growing seasons. Monocultures of ‘Gator’ and ‘Derby Supreme’ perennial ryegrass were overseeded into an established Tifway bermudagrass turf managed at golf course fairway conditions. It was hypothesized that various cultural treatments in the spring and summer could promote bermudagrass and/or discourage perennial ryegrass, and that the perennial ryegrass transition would differ depending on heat tolerance of the selected overseeding monocultures. The cultural treatments were biweekly vertical mowing, scalping, core cultivation, and vertical mowing/scalping, or two application timings of NH 4 NO 3 Chemical removal of perennial ryegrass using pronamide [3,5‐dichloro‐ N ‐(1,1‐dimethyl‐2‐propynyl)benzamide] was included as a check treatment because it is commonly used to promote transition. Bermudagrass shoot density was consistently higher in nonoverseeded plots, illustrating perennial ryegrass competition. Cultural treatments affected perennial ryegrass cover during the spring and early summer but did not hasten its ultimate disappearance. Early or late applied NH 4 NO 3 enhanced bermudagrass shoot density in both years. In contrast, plots receiving core cultivation had lower bermudagrass shoot density at the end of the transition period than the nontreated plots. Pronamide did hasten transition through 7 and 13 wk after initial treatment for 1996 and 1997, respectively. Regression analysis between natural perennial ryegrass disappearance over both years and air temperature or relative humidity indicates a significant association. This implies that cultural treatments alone may not consistently enhance natural transition of perennial ryegrass to bermudagrass. DA - 2001/// PY - 2001/// DO - 10.2135/cropsci2001.411118x VL - 41 IS - 1 SP - 118-126 SN - 0011-183X ER - TY - JOUR TI - Improved young inflorescence culture and regeneration of ifway bermudagrass (Cynodon transvaalensis x C. dactylon) AU - Qu, R. AU - Chaudhury, A. T2 - International Turfgrass Society Research Journal DA - 2001/// PY - 2001/// VL - 9 IS - 2001 SP - 198-201 ER -