TY - RPRT TI - Application rates and techniques for using composted materials in Florida DOT projects AU - Kidder, G. AU - Miller, G.L. DA - 1998/// PY - 1998/// M1 - SL-140 M3 - Publication SN - SL-140 ER - TY - RPRT TI - Florida Department of Transportation specifications for composted materials AU - Kidder, G. AU - Miller, G.L. DA - 1998/// PY - 1998/// M1 - SL-139 M3 - Publication SN - SL-139 ER - TY - RPRT TI - IFAS standardized fertilizer recommendations for environmental horticulture crops AU - Kidder, G. AU - Hanlon, E.A. AU - Yeager, T.A. AU - Miller, G.L. DA - 1998/// PY - 1998/// M1 - SL-141 M3 - Publication SN - SL-141 ER - TY - RPRT TI - Evaluation of soccer field surface hardness and ball roll characteristics for development of performance standards AU - Miller, G.L. A3 - University of Florida DA - 1998/7/23/ PY - 1998/7/23/ SP - 14 PB - University of Florida ER - TY - RPRT TI - Soil stabilization using subsurface stabilization mats for sand-based and native soil athletic fields AU - Miller, G.L. A3 - University of Florida DA - 1998/7/23/ PY - 1998/7/23/ SP - 13 PB - University of Florida ER - TY - RPRT TI - Benefits of using compost in Florida roadside plantings AU - Black, R.J. AU - Miller, G.L. DA - 1998/// PY - 1998/// SP - 6–7 M1 - ENH-126 M3 - Publication SN - ENH-126 ER - TY - BOOK TI - Roadside Turf Management Guide AU - Miller, G.L. AU - Kidder, G. AU - Black, R.J. DA - 1998/// PY - 1998/// SP - 44 PB - Florida Department of Transportation ER - TY - RPRT TI - Relationship between deficit irrigation of lawn grasses and quality parameters AU - Miller, G.L. AU - Zazuata, F.S. A3 - University of Florida DA - 1998/7/23/ PY - 1998/7/23/ SP - 14 PB - University of Florida ER - TY - RPRT TI - St. Augustinegrass tissue N evaluation using a chlorophyll meter AU - Miller, G.L. AU - Rodriguez, I.R. A3 - University of Florida DA - 1998/7/23/ PY - 1998/7/23/ SP - 13 PB - University of Florida ER - TY - RPRT TI - Nitrogen scheduling on USGA golf greens using NIRS technology AU - Miller, G.L. AU - Rodriguez, I.R. A3 - University of Florida DA - 1998/7/23/ PY - 1998/7/23/ SP - 13 PB - University of Florida ER - TY - CONF TI - Sports fields: Limitations and opportunities AU - Miller, G.L. T2 - 1998 Southern Information Exchange Group IEG-16 C2 - 1998/7/15/ C3 - Proceedings of the 1998 Southern Information Exchange Group IEG-16 CY - San Juan, Puerto Rico DA - 1998/7/15/ PY - 1998/7/15/ SP - 31–32 ER - TY - RPRT TI - Some Florida producers of composts and organic mulches AU - Black, R.J. AU - Kidder, G. AU - Rodriguez, W. AU - Miller, G.L. DA - 1998/// PY - 1998/// M1 - ENH-127 M3 - Publication SN - ENH-127 ER - TY - RPRT TI - Compost utilization by state Departments of Transportation in the United States AU - Black, R.J. AU - Miller, G.L. AU - Kidder, G. DA - 1998/// PY - 1998/// M1 - EHN-125 M3 - Publication SN - EHN-125 ER - TY - CONF TI - Compost utilization for enhancing vegetative cover of roadside soils AU - Jackson, S. AU - Kidder, J. AU - Graetz, D. AU - Black, R. AU - Miller, G. T2 - 16th World Congress of Soil Science C2 - 1998/// C3 - Proceedings of 16th World Congress of Soil Science CY - Vienna, Austria DA - 1998/// PY - 1998/// PB - International Society Soil Science ER - TY - JOUR TI - Irrigation: Use of recycled water on athletic fields AU - Miller, G.L. T2 - Sports Turf Manager DA - 1998/// PY - 1998/// VL - 16 IS - 3 SP - 10 ER - TY - JOUR TI - Turfgrass performance: Effects of mycorrhizal fungi AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 1 SP - 18 ER - TY - JOUR TI - Turfgrass establishment using a liquid source of phosphorus AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 2 SP - 30 ER - TY - JOUR TI - Interdisciplinary studies major in turfgrass science AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 3 SP - 36-39 ER - TY - JOUR TI - Compost type, rate of application and soil organic matter play a part AU - Miller, G.L. AU - Rodriguez, W. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 3 SP - 24 ER - TY - JOUR TI - Sports fields: Evaluating field performance characteristics AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 5 SP - 8 ER - TY - JOUR TI - When is overseeding over seeded? AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 6 SP - 28 ER - TY - JOUR TI - Hydrophobic soils: Managing them in turf AU - Miller, G.L. T2 - Florida Turf Digest DA - 1998/// PY - 1998/// VL - 15 IS - 6 SP - 24-26 ER - TY - JOUR TI - Recombination values for the Ms6-W1 chromosome region in different genetic backgrounds in soybean AU - Palmer, R.G. AU - Holland, J.B. AU - Lewers, K.S. T2 - Crop Science DA - 1998/// PY - 1998/// VL - 38 IS - 2 SP - 293-296 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031811862&partnerID=MN8TOARS ER - TY - JOUR TI - EPISTACY: A SAS program for detecting two-locus epistatic interactions using genetic marker information AU - Holland, J.B. T2 - Journal of Heredity DA - 1998/// PY - 1998/// DO - 10.1093/jhered/89.4.374 VL - 89 IS - 4 SP - 374-375 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031817262&partnerID=MN8TOARS ER - TY - CHAP TI - St. Augustinegrass root growth response following plant growth retardant application AU - Weinbrecht, J. S. AU - McCarty, L. B. AU - Kane, M. E. AU - Miller, G. L. AU - Best, G. R. T2 - Root Demographics and Their Efficiencies in Sustainable Agriculture, Grasslands and Forest Ecosystems PY - 1998/// DO - 10.1007/978-94-011-5270-9_57 SP - 637-650 OP - PB - Springer Netherlands SN - 9789401062183 9789401152709 UR - http://dx.doi.org/10.1007/978-94-011-5270-9_57 DB - Crossref ER - TY - JOUR TI - Beneficial insects move from flowering plants to nearby crops AU - Long, R. AU - Corbett, A. AU - Lamb, C. AU - Reberg-Horton, C. AU - Chandler, J. AU - Stimmann, M. T2 - California Agriculture AB - Marking studies demonstrated that lady beetles, lacewings, syrphid flies and parasitic wasps fed on nectar or pollen provided by borders of flowering plants around farms; many insects moved 250 feet into adjacent field crops. Studies using the elemental marker rubidium also showed that syrphid flies, parasitic wasps and lacewings fed on flowering cover crops in orchards and that some moved 6 feet high in the tree canopy and 100 feet away from the treated area. The use of nectar or pollen by beneficial insects helps them survive and reproduce. Therefore, planting flowering plants and perennial grasses around farms may lead to better biological control of pests in nearby crops. DA - 1998/9/1/ PY - 1998/9/1/ DO - 10.3733/ca.v052n05p23 VL - 52 IS - 5 SP - 23-26 LA - English SN - 0008-0845 UR - http://calag.ucanr.edu/Archive/?article=ca.v052n05p23 DB - calag.ucanr.edu Y2 - 2019/2/8/ ER - TY - JOUR TI - Registration of NC96BGTD1, NC96BGTD2, and NC96BGTD3 wheat germplasm resistant to powdery mildew AU - Murphy, JP AU - Leath, S AU - Huynh, D AU - Navarro, RA AU - Shi, A T2 - CROP SCIENCE AB - Crop ScienceVolume 38, Issue 2 cropsci1998.0011183X003800020097x p. 570-571 Registration of Germplasm Registration of NC96BGTD1, NC96BGTD2, and NC96BGTD3 Wheat Germplasm Resistant to Powdery Mildew J. P. Murphy, Corresponding Author J. P. Murphy njpm@unity.ncsu.edu Dep. of Crop ScienceCorresponding author (njpm@unity.ncsu.edu).Search for more papers by this authorS. Leath, S. Leath Dep. of Plant Pathology, North Carolina State Univ., Raleigh, NC, 27695-7629Search for more papers by this authorD. Huynh, D. Huynh Dep. of Crop ScienceSearch for more papers by this authorR. A. Navarro, R. A. Navarro Dep. of Crop ScienceSearch for more papers by this authorA. Shi, A. Shi USDA-ARS and Dep. of Plant PathologySearch for more papers by this author J. P. Murphy, Corresponding Author J. P. Murphy njpm@unity.ncsu.edu Dep. of Crop ScienceCorresponding author (njpm@unity.ncsu.edu).Search for more papers by this authorS. Leath, S. Leath Dep. of Plant Pathology, North Carolina State Univ., Raleigh, NC, 27695-7629Search for more papers by this authorD. Huynh, D. Huynh Dep. of Crop ScienceSearch for more papers by this authorR. A. Navarro, R. A. Navarro Dep. of Crop ScienceSearch for more papers by this authorA. Shi, A. Shi USDA-ARS and Dep. of Plant PathologySearch for more papers by this author First published: 01 March 1998 https://doi.org/10.2135/cropsci1998.0011183X003800020097xCitations: 11AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume38, Issue2March–April 1998Pages 570-571 RelatedInformation DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020097x VL - 38 IS - 2 SP - 570-571 SN - 0011-183X ER - TY - JOUR TI - Gene turns fungus [Cercospora] against itself AU - Lee, J. T2 - Agricultural Research (Washington) DA - 1998/// PY - 1998/// VL - 46 IS - 8 SP - 10 ER - TY - JOUR TI - Variable rate nutrient management for corn-wheat-soybean cropping systems AU - Heiniger, R. W. T2 - Better Crops With Plant Food DA - 1998/// PY - 1998/// VL - 82 IS - 4 SP - 11 ER - TY - JOUR TI - Registration of low palmitic acid soybean germplasm lines N94-2575 and C1943 AU - Burton, JW AU - Wilcox, , JR AU - Wilson, RF AU - Novitzky, WP AU - Rebetzke, GJ T2 - CROP SCIENCE AB - Crop ScienceVolume 38, Issue 5 cropsci1998.0011183X003800050059x p. 1407-1407 Registration of Germplasm Registration of Low Palmitic Acid Soybean Germplasm Lines N94-2575 and C1943 J. W. Burton, J. W. BurtonSearch for more papers by this authorJ. R. Wilcox, J. R. WilcoxSearch for more papers by this authorR. F. Wilson, R. F. WilsonSearch for more papers by this authorW. P. Novitzky, W. P. NovitzkySearch for more papers by this authorG. J. Rebetzke, G. J. RebetzkeSearch for more papers by this author J. W. Burton, J. W. BurtonSearch for more papers by this authorJ. R. Wilcox, J. R. WilcoxSearch for more papers by this authorR. F. Wilson, R. F. WilsonSearch for more papers by this authorW. P. Novitzky, W. P. NovitzkySearch for more papers by this authorG. J. Rebetzke, G. J. RebetzkeSearch for more papers by this author First published: 01 September 1998 https://doi.org/10.2135/cropsci1998.0011183X003800050059xCitations: 7AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume38, Issue5September–October 1998Pages 1407-1407 RelatedInformation DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800050059x VL - 38 IS - 5 SP - 1407-1407 SN - 0011-183X ER - TY - BOOK TI - What business wants from higher education AU - Oblinger, D. G. AU - Verville, A.-L. DA - 1998/// PY - 1998/// PB - Phoenix, AZ: Oryx Press SN - 1573562068 ER - TY - BOOK TI - The future compatible campus : Planning, designing, and implementing information technology in the academy DA - 1998/// PY - 1998/// PB - Bolton, MA: Anker Publishing Co. SN - 1882982193 ER - TY - JOUR TI - Weed management in North Carolina peanut with flumioxazin AU - Wilcut, J. W. AU - Askew, S. D. AU - Bailey, W. A. AU - Cranmer, J. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 56-57 ER - TY - JOUR TI - Optimizing production workshop--ultra narrow row cotton for the Southeast AU - Edmisten, K. L. AU - York, A. C. AU - Culpepper, A. S. AU - Stewart, A. M. AU - Maitland, J. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 84 ER - TY - JOUR TI - Flumioxazin systems for weed management in North Carolina peanuts AU - Askew, S. D. AU - Bailey, W. A. AU - Wilcut, J.W. AU - Cranmer, J. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 60 ER - TY - JOUR TI - Effects of turfgrass growth regulators on lateral development of hybrid and common bermudagrass AU - Fagerness, M. J. AU - Yelverton, F. H. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 65-66 ER - TY - JOUR TI - Weed management with buctril and staple mixtures in BXN cotton AU - Paulsgrove, M. D. AU - Wilcut, J. W. AU - Askew, S. D. AU - Collins, J. R. AU - Hinton, J. D. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 264-265 ER - TY - JOUR TI - Weed management in soybean with combinations of PPI herbicides and cloransulam-methyl post AU - Askew, S. D. AU - Bailey, W. A. AU - Wilcut, J.W. AU - Langston, V. B. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 274 ER - TY - JOUR TI - Velvetleaf interference and seed-rain dynamics in cotton AU - Bailey, W. A. AU - Askew, S. D. AU - Wilcut, J. W. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 266-267 ER - TY - JOUR TI - The effect of paclobutrazol on the relative growth of annual bluegrass and creeping bentgrass T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 248 ER - TY - JOUR TI - Relationship of weed populations and herb in selected North Carolina peanut fields AU - Jordan, D. L. AU - Coble, H. D. AU - Brandenburg, R. L. AU - Bailey, J. E. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 215-216 ER - TY - RPRT TI - Reduction of turbidity in sedimentation basins AU - Hesterberg, D. A3 - Raleigh, NC: University of North Carolina Water Resources Research Institute C6 - 1998 Apr. 1 DA - 1998/// PY - 1998/// PB - Raleigh, NC: University of North Carolina Water Resources Research Institute ER - TY - JOUR TI - Red rice (Oryza sativa) control and seedhead reduction with glyphosate AU - Askew, S. D. AU - Shaw, D. R. T2 - Weed Technology DA - 1998/// PY - 1998/// VL - 12 IS - 1998 SP - 504-506 ER - TY - JOUR TI - Preliminary evaluation of clearigate and reward, alone and in combination, on duckweed, watermeal, and mosquito fern AU - Kay, S.H. AU - Hoyle, S.T. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 198 ER - TY - RPRT TI - Pesticides in North Carolina ground water AU - McLaughlin, R. A3 - Raleigh, NC: University of North Carolina Water Resources Research Institute C6 - 1998 Apr. 1 DA - 1998/// PY - 1998/// PB - Raleigh, NC: University of North Carolina Water Resources Research Institute ER - TY - JOUR TI - North Carolina measured crop performance: small grains 1998 AU - Bowman, D. T. T2 - Crop Science Research Report (North Carolina State University. Dept. of Crop Science) DA - 1998/// PY - 1998/// IS - 173 ER - TY - JOUR TI - Moss control in bentgrass putting greens T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 75 ER - TY - JOUR TI - Italian ryegrass (Lolium multiflorum Lam.) response to residual phosphorus levels in winter wheat AU - Perez-Fernandez, T.M. AU - Coble, H.D. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 244 ER - TY - JOUR TI - Influence of moisture stress and temperature on sicklepod germination AU - Burleson, A. W. AU - Wilcut, J. W. AU - Keyes, B. AU - Askew, S. D. AU - Bailey, W. A. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 254-255 ER - TY - JOUR TI - Influence of bulb packing systems on forcing of Dutch-grown Hippeastrum (Amaryllis) as flowering potted plants in North America AU - Yelverton, F. H. T2 - Grounds Maintenance DA - 1998/// PY - 1998/// VL - 33 IS - 9 SP - 20,-2224 ER - TY - JOUR TI - Impact of mowing on growth and spread of green kyllinga (Kyllinga brevifolia) and yellow nutsedge (Cyperus esculentus) T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 70-71 ER - TY - JOUR TI - Evaluation of Strongarm (DE 564, diclosulam) for weed control in southeastern peanuts AU - Bailey, W. A. AU - Wilcut, J. W. AU - Jordan, D. L. AU - Askew, S. D. AU - Hinton, J. D. AU - Langston, V. B. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 59 ER - TY - JOUR TI - Effects of trinexapac-ethyl and paclobutrazol on ball roll and summer stress of creeping bentgrass AU - Yelverton, F. H. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 68 ER - TY - JOUR TI - Effect of manipulation of seeding rate on diboa-glucoside, diboa, and boa levels in rye AU - Wickliffe, W. B. AU - Yelverton, F. H. AU - Worsham, A. D. AU - Nagabhushana, G. G. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 199 ER - TY - JOUR TI - Dormant season herbicide treatments for kudzu control AU - Kay, S.H. AU - Yelverton, F.H. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 190-191 ER - TY - BOOK TI - Carostan flaccidgrass: Establishment, adaption, production management, forage quality, and utilization AU - Belesky, D. P. AU - Burns, J.C. AU - Chamblee, Douglas S. AU - Daniel, Dorsey W. AU - Ruiter, J.M. AU - Fisher, D.S. AU - Green, J. T. AU - Mochrie, R. D. AU - Mueller, J. P. AU - Pond, K. R. AU - Timothy, D. H. CN - SB197 .C37 1998 DA - 1998/// PY - 1998/// PB - Raleigh, NC: N.C. Agricultural Research Service, N.C. State University ER - TY - JOUR TI - A regional evaluation of new technologies for weed management in conventional-tillage cotton AU - Wilcut, J. W. AU - Snipes, C. E. AU - Nichols, R. L. AU - Hayes, R. M. AU - Chandler, M. AU - Bridges, D. C. AU - Brecke, B. J. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 52-53 ER - TY - BOOK TI - The released Chinese soybean cultivars and their pedigree analysis AU - Cui, Z. AU - Gai, J. AU - Carter, T. E., Jr. AU - Qiu, J. AU - T., Zhao DA - 1998/// PY - 1998/// PB - China Agriculture Press SN - 7109050254 ER - TY - JOUR TI - Weed control in cotton with different tillage systems and herbicide resistances AU - Askew, S. D. AU - Bailey, W. A. AU - Wilcut, J.W. AU - Hinton, J. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 866 ER - TY - JOUR TI - Staple/MSMA combinations for sicklepod (Senna obtusifolia) control in cotton AU - Jennings, K. M. AU - York, A. C. AU - Culpepper, A. S. AU - Batts, R. B. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 843-844 ER - TY - JOUR TI - Roundup Ready systems for weed control in North Carolina AU - Bailey, W. A. AU - Askew, S. D. AU - Wilcut, J. W. AU - Hinton, J. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 862-863 ER - TY - JOUR TI - Potential for cotoran carryover to flue-cured tobacco AU - Batts, R. B. AU - York, A. C. AU - Yelverton, F. H. AU - Bradley, A. L. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 873 ER - TY - JOUR TI - Nutsedge (Cyperus esculentus) management in continuous cotton with zorial-based systems AU - Wilcut, J. W. AU - Bridges, D. C. AU - McLean, H. S. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 872-873 ER - TY - JOUR TI - Fruit abscission and yield response of Roundup-Ready cotton to topical applications of glyphosate AU - Kalaher, C. J. AU - Coble, H. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 849 ER - TY - JOUR TI - Command 3ME and roundup systems for weed control in roundup ready cotton AU - Askew, S. D. AU - Bailey, W. A. AU - Wilcut, J.W. AU - Hinton, J. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 860 ER - TY - JOUR TI - Buctril and MSMA combinations for sicklepod (Senna obtusifolia) management in BXN cotton AU - Paulsgrove, M. D. AU - Wilcut, J. W. AU - Hinton, J. D. AU - Collins, J. R. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 854-855 ER - TY - JOUR TI - A beltwide perspective on new weed management technologies in cotton AU - Wilcut, J. W. AU - Brecke, B. J. AU - Bridges, D. C. AU - Chandler, J. M. AU - Hayes, R. AU - Nichols, R. L. AU - Snipes, C. E. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 846-847 ER - TY - JOUR TI - Weed management in glyphosate-tolerant cotton AU - Culpepper, A. S. AU - York, A. C. T2 - Journal of Cotton Science DA - 1998/// PY - 1998/// VL - 2 IS - 4 SP - 174-185 ER - TY - JOUR TI - Using GPS to scout cotton for variable rate PIX (Mepiquat chloride) application AU - Thurman, M. E. AU - Heiniger, R. W. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 2 IS - 1998 SP - 1499-1502 ER - TY - JOUR TI - Cotton germplasm diversity and its importance to cultivar development AU - Van Esbroeck, G. AU - Bowman, D. T. T2 - Journal of Cotton Science DA - 1998/// PY - 1998/// VL - 2 IS - 3 SP - 121-129 ER - TY - JOUR TI - Resistance to root-knot, reinform, and soybean cyst nematodes in soybean breeding lines AU - Davis, E. L. AU - Meyers, D. M. AU - Burton, J. W. AU - Burton, K. R. T2 - Journal of Nematology DA - 1998/// PY - 1998/// VL - 30 IS - 4, Suppl. SP - 530-541 ER - TY - CONF TI - Nitrification options for swine wastewater treatment AU - Vanotti, M. B. AU - Szogi, A. A. AU - Hunt, P. G. AU - Humenik, F. J. AU - Rice, J. M. C2 - 1998/// C3 - Animal Production Systems and the Environment: An International Conference on Odor, Water Quality, Nutrient Management and Socioeconomic Issues: Proceedings, July 19-22, 1998 DA - 1998/// SP - 795-800 M1 - 1998 PB - Ames, Iowa: Iowa State University of Science and Technology ER - TY - JOUR TI - Natural resistance of Malus to adult Japanese beetles AU - Fulcher, A. F. AU - Ranney, T. G. AU - Burton, J. D. AU - Walgenbach, J. F. AU - Danehower, D. A. T2 - American Nurseryman DA - 1998/// PY - 1998/// VL - 188 IS - 10 SP - 56-57 ER - TY - JOUR TI - Influence of sample size on cotton shoot nitrogen accumulation: lint yield ratios AU - Hunt, P. G. AU - Matheny, T. A. AU - Bauer, P. J. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 675-677 ER - TY - JOUR TI - Flow proportional and time composite estimates of nutrient loading from an eastern Coastal Plain watershed AU - Stone, K. C. AU - Johnson, M. H. AU - Novak, J. M. AU - Watts, D. W. AU - Hunt, P. G. T2 - Paper (American Society of Agricultural Engineers) DA - 1998/// PY - 1998/// VL - 98 IS - 2153 SP - 1-14 ER - TY - CONF TI - Constructed wetland systems for swine wastewater treatment AU - Rice, J. M. AU - Szogi, A. A. AU - Broome, S. W. AU - Humenik, F. J. AU - Hunt, P. G. C2 - 1998/// C3 - Animal Production Systems and the Environment: An International Conference on Odor, Water Quality, Nutrient Management and Socioeconomic Issues: Proceedings, July 19-22, 1998 DA - 1998/// SP - 501-505 M1 - 1998 PB - Ames, Iowa: Iowa State University of Science and Technology ER - TY - JOUR TI - Pesticides and metabolites in the shallow groundwater of an eastern Coastal Plain watershed AU - Novak, J. M. AU - Watts, D. W. AU - Stone, K. C. AU - Johnson, M. H. AU - Hunt, P. G. T2 - Transactions of the ASAE AB - The occurrence of pesticides in drinking water sources is a public concern because of potential adverse healtheffects. We report the results of a three-year study to assess the occurrence of pesticides and metabolites in shallowgroundwater in a USDA Water Quality Demonstration Project (WQDP). The Herrings Marsh Run (HMR) watershed islocated in the eastern Coastal Plain region of North Carolina and has similar characteristics of other regionalagricultural-intensive watersheds. Ninety-two shallow groundwater wells were installed on farms around the watershed inlate 1992 and early 1993. Water samples were collected monthly from March 1993 to March 1995 and collected quarterlyfor the remainder of 1995 and early 1996. The samples (n = 2598) were initially screened for 11 pesticides (8 triazines, 2chloroactamides, 1 methylester) using immunoassay techniques. The positive detections (n = 266) were further analyzedby gas chromatographic (GC) and GC/MS (mass spectrometric) procedures. During the study period, we found that themajority (91%) of the wells had no detections for 11 compounds commonly used in the watershed. Pesticides wereconsistently detected in four wells, but the concentrations were usually below the health advisory limit (HAL). Overall,alachlor was the most frequently detected pesticide. The lack of 11 commonly used pesticides in a high number of wellssuggests that these pesticides have had a minimal impact on the quality of HMR shallow groundwater. DA - 1998/// PY - 1998/// DO - 10.13031/2013.17312 VL - 41 IS - 5 SP - 1383-1390 ER - TY - JOUR TI - Nitrogen accumulation in cotton grown continuously or in rotation with peanut using subsurface microirrigation and GOSSYM/COMAX management AU - Hunt, PG AU - Bauer, PJ AU - Camp, CR AU - Matheny, TA T2 - CROP SCIENCE AB - Excessive N application to cotton (Gossypium hirsutum L.) is an unnecessary cost and a potential cause of elevated groundwater N. The objectives of this study were to determine if seed yields or excess N were affected by timing of N application via buried microirrigation tubing, tubing spacing, or peanut (Arachis hypogaea L.) rotation. The experimental design was a randomized complete block in split-plot arrangement with four replications. The main plots (continuous cotton and peanut-cotton rotation) were planted with cotton cultivar PD 3 in May of 1991 through 1994 on an Eunola loamy sand (fine-loamy, siliceous, thermic Aquic Haphidult). Water and N were applied through microirrigation tubing that was buried 0.30 m directly under each row (IR) or under alternate row middles (AM). Sidedress-N was applied in one 112-kg ha−1 application (STD); five, 22-kg ha−1 increments (INC); or 11- to 22-kg ha−1 increments when required by GOSSYM/COMAX (GC) [a cotton growth model/expert system]. Rotation did not significantly affect any of the measured parameters. Cotton managed with the IR-STD treatment had the highest seed yield, 2.02 Mg ha−1 yr−1. The GC management did not improve seed yield, but it did reduce excess N (fertilizer N - seed N) to <20 kg ha−1 yr−1. The best overall treatment was AM-GC. It had 1.87 Mg ha−1 yr−1 seed yield, 8 kg ha−1 yr−1 excess N, 45 kg less N applied, and 50% less tubing installed. Cotton managed by AM-GC also had a low (9.2) ratio of accumulated shoot N per 100 kg of lint. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020023x VL - 38 IS - 2 SP - 410-415 SN - 0011-183X ER - TY - JOUR TI - Nitrate-N distribution and trends in shallow groundwater on an eastern Coastal Plains watershed AU - Stone, K. C. AU - Hunt, P. G. AU - Johnson, M. H. AU - Matheny, T. A. T2 - Transactions of the ASAE AB - Nonpoint source pollution from agriculture has been a major concern, particularly where intensiveagricultural operations exist near environmentally sensitive waters. To address these nonpoint source pollution concerns, a Water Quality Demonstration Project (WQDP) was initiated on the Herrings Marsh Run (HMR) watershed in Duplin County, North Carolina. The WQDP was implemented to determine water quality benefits from voluntary adoption of improved management practices. In the WQDP, 84 groundwater monitoring well sites were established on 21 farms selected to represent the major farming practices on the watershed. On the HMR watershed, nitrate-N contamination of groundwater was not a wide spread problem. Seventy-four percent of the groundwater monitoring sites had nitrate-N less than the drinking water standard of 10 mg/L. Mean nitrate-N concentrations were below 10 mg/L on 16 of the 21 farms. Of the four farms with nitrate-N exceeding 10 mg/L, one farm had mean nitrate-N that exceeded 20 mg/L. This farm had an undersized and overloaded swine wastewater spray field. After the spray field was expanded and application rates were reduced, groundwater nitrate-N concentrations declined; but they continued to exceed 20 mg/L. Other farms with swine waste spray fields had mean groundwater nitrate-N concentrations <20 mg/L throughout the study period. Groundwater nitrate-N concentrations under row crops were <10 mg/L on all but two farms. Three of the four farms with nitrate-N concentrations exceeding 10 mg/L were in a subwatershed of the HMR that had the highest concentration of animal waste application and excess nitrogen applied. Of the 21 farms, three farms had a significant increasing trend in groundwater nitrate-N while four farms had a significant decreasing trend. The overloaded swine wastewater spray field had a significant decreasing nitrate-N trend. Most farms with concentrations less than 10 mg/L had no detectable trend in nitrate-N concentration during the study. These findings indicate that nitrate-N contamination of groundwater is not a widespread problem on the HMR watershed even though it is intensively farmed. DA - 1998/// PY - 1998/// DO - 10.13031/2013.17157 VL - 41 IS - 1 SP - 59-64 ER - TY - JOUR TI - Measuring mechanical impedance in clayey gravelly soils AU - Stolf, R. AU - Cassel, D. K. AU - King, L. D. AU - Reichardt, K. T2 - Revista Brasileira De Ciencia Do Solo AB - Mechanical impedance of clayey and gravelly soils is often needed to interpret experimental results from tillage and other field experiments. Its measurement is difficult with manual and hydraulic penetrometers, which often bend or break in such soils. The purpose of this study was to evaluate the feasibility of a hand-operated "Stolf" impact penetrometer to measure mechanical impedance (soil resistance). The research was conducted in Raleigh, North Carolina, USA (35º 45'N, 78º 42'W, elevation 75 m). Corn was planted on April 19, 1991. Penetrometer measurements were taken on May 10, 1991, in 5 cm intervals to 60 cm at 33 locations on a transect perpendicular to the corn rows in each of four tillage treatments. The data permitted three-dimensional displays showing how mechanical impedance changed with depth and distance along the transect. The impact penetrometer proved to be a useful tool to collect quantitative mechanical impedance data on "hard" clayey and/or gravelly soils which previously were difficult to reliably quantify. DA - 1998/// PY - 1998/// DO - 10.1590/s0100-06831998000200003 VL - 22 IS - 1998 SP - 189-196 ER - TY - JOUR TI - Iron oxides erodibility interactions for soils of the Memphis catena AU - Rhoton, FE AU - Lindbo, DL AU - Romkens, MJM T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Abstract In the Memphis catena, the well‐drained Memphis (fine silty, mixed, active, thermic Typic Hapludalfs) is more erodible than the moderately well‐drained Loring (fine silty, mixed, active, thermic Oxyaquic Fragiudalfs) and Grenada (fine silty, mixed, active, thermic Glossic Fragiudalfs). We hypothesized that soil wetness and Fe oxide status affects the erodibility of these soils. Samples (<2 mm) of A‐ and B‐horizons, collected from representative pedons at five locations, were characterized for standard physical and chemical properties. Simulated rainfall was applied (64 mm h ‐1 ) to additional samples (<8 mm) in a rainfall simulator pan that had a 0.6 m × 0.6 m test area. Water dispersible clay (WDC) and soil loss averaged 7.2% and 9.21 Mg ha ‐1 for Memphis, 6.8% and 8.85 Mg ha ‐1 for Loring, and 6.1% and 8.71 Mg ha ‐1 for Grenada. Sediment Fe o , Fe d , and Fe o /Fe d ratios were about 0.80, 1.5, and 0.50 times that of the soil, respectively. Correlation coefficients ( r ) for WDC and soil loss vs. Fe oxide variables exceeded 0.90 in some horizons, whereas, organic C (OC) and % clay were generally <0.60. However, OC vs. % sediment <53 µm had r values of 0.87 compared to 0.59 for some Fe oxide variables. Regression models derived for WDC and soil loss had Fe oxide parameters as principal variables in the best fit models and coefficients of determination that ranged from 0.208 to 0.922 (significant at P ≤ 0.01). Results suggest that Fe oxides are more important than OC and clay content for determining the erodibility of these soils, particularly Fe o /Fe d ratios which are negatively correlated with WDC and soil loss. DA - 1998/// PY - 1998/// DO - 10.2136/sssaj1998.03615995006200060030x VL - 62 IS - 6 SP - 1693-1703 SN - 0361-5995 ER - TY - CONF TI - Improving water quality through conservation practices AU - Cook, M. G. AU - Hunt, P. G. AU - Canterberry, J. H. A2 - L. S. Bhushan, I. P. Abrol A2 - Rao, M. S. Rama Mohan C2 - 1998/// C3 - Soil and water conservation: Challenges and opportunities: 8th International Soil Conservation Conference CN - S622.2.I5 1994 DA - 1998/// VL - 1 SP - 304-310 PB - Rotterdam: Balkema ER - TY - JOUR TI - Identification of heat sensitive proteins during roasting of peanut seed AU - Basha, SM AU - Ying, M AU - Young, CT T2 - JOURNAL OF FOOD QUALITY AB - ABSTRACT Peanut ( Arachis hypogaea L) seed were heated at 125C and 150C between 0 to 24 min and the seed proteins were extracted with 0.1 M sodium phosphate buffer, pH 2.5. The soluble and insoluble proteins were analyzed to determine changes in protein and polypeptide composition during heating. Acid soluble proteins were more susceptible to thermal breakdown than acid insoluble proteins. Within the acid soluble fraction, some proteins and polypeptides were more readily degraded than the others. In the acid insoluble fraction, except for the loss of a 70,000 Dalton polypeptide no other major changes were observed. Changes in protein composition were more rapid at 150C heating than at 125C heating. These data suggest that the proteins of the acid soluble fraction are highly sensitive to heating and thus may have a role in flavor volatile production during roasting of the peanut. DA - 1998/12// PY - 1998/12// DO - 10.1111/j.1745-4557.1998.tb00538.x VL - 21 IS - 6 SP - 485-496 SN - 1745-4557 ER - TY - JOUR TI - Far-red light affects photosynthate allocation and yield of tomato over red mulch AU - Kasperbauer, MJ AU - Hunt, PG T2 - CROP SCIENCE AB - Plastic mulches are frequently used by both large‐ and small‐scale tomato ( Lycopersicon esculentum Miller) growers to conserve water, control weeds, and keep fruit clean. We hypothesized that changing mulch color to reflect more red light (R) and a higher far‐red (FR) to R photon ratio (FR/R) would keep those benefits and improve tomato yield by altering phytochrome‐mediated regulation of photosynthate allocation. Photodegradable and nondegradable forms of red plastic mulch were developed to our specifications. Number, size, and total fruit produced over the red plastic mulches were compared with those over standard black plastic. Photodegradable red mulch (placed over a layer of black plastic) increased fruit yield while it was intact, but yield dropped to that of the black control after the red plastic degraded. Nondegradable red plastic resulted in greater yield. Early crop yield advantage of red mulch was evident whether it was placed directly over soil or over a layer of black plastic. We conclude that increased tomato yield over the new red plastic mulch was caused by reflection of FR to the growing plants and its subsequent phytochrome‐mediated regulation of photosynthate allocation to developing fruit. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800040015x VL - 38 IS - 4 SP - 970-974 SN - 0011-183X ER - TY - JOUR TI - Effects of agricultural runoff dispersion on nitrate reduction in forested filter zone soils AU - Verchot, LV AU - Franklin, EC AU - Gilliam, JW T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Abstract Forested filter zones (FFZ) are being used more frequently for remediation of agricultural non‐point source pollution. The objective of this study was to determine the effects of short‐term dispersal (1–2 yr) of agricultural runoff on the denitrification potential of the soil microbial population and denitrification rates, to a depth of 1 m, in forest soils in two small watersheds (W1 and W2) in the Piedmont of North Carolina. Each watershed consisted of a field and a FFZ. Denitrification potential was measured in a series of soil slurry incubations of soils from inside the FFZ that received agricultural runoff and from soils immediately adjacent to the FFZ that received no runoff (control). Soils were amended with both glucose and nitrate (G + NO 3 ) to ensure adequate supply of substrate and energy source. Denitrification rates were measured at ambient C conditions in a similar incubation with only NO 3 ‐N amendment (NO 3 ). We measured NO 3 ‐N disappearance in both incubations and reported loss as a percentage of initial concentrations. For the FFZ soils, >80% of the added NO 3 ‐N was lost in the G + NO 3 incubation from soils from the upper 50 cm in W1 and from the upper 30 cm in W2. In control soils, high levels of NO 3 ‐N loss were observed in only the upper 20 cm of the profile in W1, and in W2 surface soils had significantly lower denitrification potential than FFZ soils at all depths. Denitrification potential was greatly enhanced ( P = 0.05) throughout the entire first 100 cm in the first FFZ and in the surface 40 cm in the second FFZ. Denitrification rates under ambient C conditions were higher (>40%) in the surface 20 cm of the profile of the FFZ in W1, compared with the unexposed control (∼20%), but no enhancement was observed on W2. Exposure of soil to agricultural runoff had a significant impact on the soil microbial community. Denitrification potential in subsoil was limited by the absence of denitrifiers in unexposed soils, but subsoils exposed to agricultural runoff had a significant denitrifier population. The fact that higher denitrification potential did not translate to higher denitrification rates in these incubations indicates that C availability limited the denitrification process at all depths in these Piedmont forest soils. DA - 1998/// PY - 1998/// DO - 10.2136/sssaj1998.03615995006200060033x VL - 62 IS - 6 SP - 1719-1724 SN - 0361-5995 ER - TY - CHAP TI - Demonstration of the functionality of a self-contained modular lysimeter design for studying the fate and transport of chemicals in soil under field conditions AU - Van Wesenbeeck, I. AU - Schabacker, D. J. AU - Winton, K. AU - Heim, L. AU - Winberry, M. W. AU - Williams, M. D. AU - Weber, J. B. AU - Swain, L. R. AU - Velagaleti, R. T2 - The lysimeter concept: Environmental behavior of pesticides AB - Analytical Bio-Chemistry (ABC) Laboratories, Inc. has developed a modular lysimeter design and has instrumented and installed the lysimeters at four field sites in the United States: Missouri (MO), Iowa (IA), Illinois (IL), North Carolina (NC) and Ontario (ON), Canada. The modular lysimeter design consists of three components that are readily assembled and installed in the field; an intact soil core, a run-off (overflow) collection system, and a leachate collection system. In NC, the lysimeters were installed at the NC State University Experimental Station site in Clayton with a Novartis Crop Protection development compound, designated as 14C-XYZ for confidentiality reasons. The fate and transport of the chemical was studied over a period of 90 days using intact 90 cm deep, 15 cm diameter soil columns containing sandy soil. Parent compound degraded into an acid metabolite that was detected down to 60 cm in the soil profile. Parent compound was not observed at a soil depth below 15 cm. The decline of the parent compound coincided with the formation of the acid metabolite which degraded into four additional metabolites. Lysimeters 30 cm in diameter and 75-90 cm deep were instrumented and installed at four locations (MO, IA, IL, and ON) to study the fate and transport of a DowElanco development compound, designated as 14C-DEC for confidentiality reasons. In these experiments, the fate and transport of the test compound and a bromide tracer in the lysimeters were compared with that in the field plots for 12 months. Preliminary results from IA and MO suggest that degradation and solute transport processes were similar in the soil plots and lysimeters, and that the 30 cm diameter pipe lysimeters approach the representative elementary volume (REV) for solute transport processes at the IA site. The modular pipe lysimeter design offers significant advantages in terms of assessing solute mass balance, mobility, variability (through increased replication) and reduced cost of radioactive waste compared to soil plot studies. CN - S592.6.P43 L948 1998 PY - 1998/// DO - 10.1021/bk-1998-0699.ch009 SP - 122-135 PB - Washington, DC: American Chemical Society ER - TY - JOUR TI - Characterization of biogenic nitric oxide source strength in the southeast United States AU - Aneja, VP AU - Roelle, PA AU - Robarge, WP T2 - ENVIRONMENTAL POLLUTION AB - Emissions of nitric oxide (NO) were measured during the summer of 1995 from 4 crops, located at three different sites throughout North Carolina. These sites were chosen to represent major physiographic regions of the Southeast US, in an effort to compare fluxes from different agriculturally managed soils. Emission rates were determined using a dynamic flow-through chamber system. In order to understand the NO flux from the different soil and crop types, measurements were made on corn and soybean crops in the coastal region, tobacco in the Piedmont region, and corn in the upper Piedmont region of North Carolina. Average NO fluxes were 5.5 f 2.2 ng N me2 s-‘, 20.7 + 19.2 ng N me2 s-‘, 4.1 + 1.4 ng N m-2s-1, and 8.5 2 4.9 ng N me2 s-l respectively for corn and soybean in the coastal region, tobacco in the Piedmont region, and corn in the upper Piedmont region. We were only able to detect an exponential dependence of NO flux on soil temperature at two of the locations. Tbe composite data of all the research sites revealed a general trend of increasing NO flux with soil water content or increasing extractable nitrogen in the soil, however, the day to day variations within each site did not reveal the same trends. We feel that acquisition of a soil NO flux data set in this fashion, which consists of observations collected over different points in both space and time, makes attempts to model soil NO flux in terms of different soil parameters difficult. DA - 1998/// PY - 1998/// DO - 10.1016/S0269-7491(98)80035-3 VL - 102 SP - 211-218 SN - 0269-7491 KW - natural emissions KW - nitric oxide KW - corn KW - soybean KW - tobacco KW - agricultural soils KW - soil moisture content KW - soil extractable nitrogen ER - TY - JOUR TI - An improved reversed-phase thin-layer chromatography method for separation of fatty acid methyl esters AU - Marquardt, TC AU - Wilson, RF T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Resolution of fatty acid methyl esters (FAME) by thin‐layer chromatography often is complicated by co‐migration of certain acyl‐isomers in heterogeneous mixtures. However, a novel reversed‐phase thin‐layer chromatography method which employs 10% (wt/vol) silver nitrate in a mobile phase containing acetonitrile/1,4‐dioxane/acetic acid (80:20:1, vol/vol/vol) allows one‐dimensional resolution of a wide range of acyl‐methyl esters. This innovation enables improved separation of saturated FAME ranging from C 12 to C 22 , and geometric isomers of C 14 to C 22 unsaturated FAME by thin‐layer chromatography. DA - 1998/12// PY - 1998/12// DO - 10.1007/s11746-998-0346-7 VL - 75 IS - 12 SP - 1889-1892 SN - 0003-021X KW - argentation chromatography KW - fatty acid methyl esters KW - reversed-phase thin-layer chromatography KW - separation ER - TY - JOUR TI - The potential of a summer drawdown to manage monoecious hydrilla AU - Poovey, A. G. AU - Kay, S. H. T2 - Journal of Aquatic Plant Management DA - 1998/// PY - 1998/// VL - 36 IS - 1998 July SP - 127-130 ER - TY - JOUR TI - Impact of swine waste application on ground and stream waterquality in an eastern coastal plain watershed AU - Stone, K. C. AU - Hunt, P. G. AU - Humenik, F. J. AU - Johnson, M. H. T2 - Transactions of the ASAE AB - Nonpoint source pollution from agriculture has been a major concern, particularly where intensiveagricultural operations exist near environmentally sensitive waters. To address these concerns, a water quality projectwas initiated in Duplin County, North Carolina, in the 2044-ha Herrings Marsh Run watershed. A swine farm within thismonitored watershed expanded its operation from 3,300 to more than 14,000 animals. Groundwater nitrate-N increasedsignificantly in three of the seven wells located adjacent to the spray field and in the adjoining riparian zone. Streamnitrate-N concentrations have increased after the expansion of the swine operation in the colder months, butconcentrations have remained approximately the same during the warmer months. Stream ammonia-N meanconcentrations after expansion have increased as well as the frequency and magnitude of ammonia-N concentrationspikes. Ortho-phosphate concentrations in the stream water have been relatively consistent over the study period. Theriparian zone is reducing the impact of spray field groundwater nitrate concentrations and ammonia loadings in anadjacent stream. DA - 1998/// PY - 1998/// DO - 10.13031/2013.17342 VL - 41 IS - 6 SP - 1665-1670 ER - TY - JOUR TI - Effects of a low rate, of aldicarb on soybean and associated pest interactions in fields infested with Heterodera glycines AU - Koenning, S. R. AU - Coble, H. D. AU - Bradley, J. R. AU - Barker, K. R. AU - Schmitt, D. P. T2 - Nematropica DA - 1998/// PY - 1998/// VL - 28 IS - 2 SP - 205-211 ER - TY - JOUR TI - Comparative evapotranspiration of seventeen buffalograss (Buchloe dactyloides (Nutt.) Engelm.) genotypes. AU - Bowman, D. C. AU - Devitt, D. A. AU - Huff, D. R. AU - Miller, W. W. T2 - Journal of Turfgrass Management DA - 1998/// PY - 1998/// VL - 2 IS - 4 SP - 1-10 ER - TY - JOUR TI - Zinc and copper toxicity in peanut, soybean, rice, and corn in soil mixtures AU - Borkert, CM AU - Cox, FR AU - Tucker, MR T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Applications of zinc (Zn) and copper (Cu) at excessive rates may result in phytotoxicity. Experiments were conducted with mixtures of soils that were similar except for their Zn and Cu levels. The critical toxicity levels (CTL) in the soils and plants for these elements were determined. Peanut (Arachis hypogaea L.), soybean [Glycine max (L.) Merr.], corn (Zea mays L.), and rice (Oryza sativa L.) were the crops grown. One soil mixture had Mehlich 3‐extractable Zn concentrations up to 300 mg dm‐3 with no corresponding increase in soil Cu; two soil mixtures had soil Zn concentrations up to 400 and 800 mg dm‐3 with a corresponding increase in soil Cu up to 20 and 25 mg dm‐3, respectively; and four soil mixtures had no increase in soil Zn, but had Mehlich 1‐extractable Cu concentrations from 6 to 286 mg kg‐1. Under a given set of greenhouse conditions, the estimated Mehlich 3‐extractable Zn CTL was 36 mg dm‐3 for peanut, 70 mg dm‐3 for soybean, between 160 and 320 mg dm‐3 for rice, and >300 mg dm‐3 for corn. No soil Cu CTL was apparent for peanut or soybean, but for corn it was 17 mg dm‐3 and for rice 13 mg dm‐3. With different greenhouse procedures and the Mehlich 1 extractant, the soil CTL for rice was only 4.4 mg kg‐1. Therefore, peanut and soybean were more sensitive to Zn toxicity, whereas corn and rice were more sensitive to Cu toxicity. Plant Zn CTL for peanut was 230 mg kg‐1, while that for soybean was 140 mg kg‐1. Copper appeared to be toxic to corn and rice at plant concentrations exceeding 20 mg kg‐1. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809370171 VL - 29 IS - 19-20 SP - 2991-3005 SN - 0010-3624 ER - TY - JOUR TI - Quality of hard red winter wheat grown under high temperature conditions during maturation and ripening AU - Gibson, LR AU - McCuskey, PJ AU - Tilley, KA AU - Paulsen, GM T2 - CEREAL CHEMISTRY AB - ABSTRACT High temperature during grain filling has been identified as a major factor in the end‐use properties of bread wheat ( Triticum aestivum L.). Our objectives were to assess the effect of high temperature during maturation on the grain characteristics, milling quality, and flour quality of hard red winter wheat. In three separate experiments, plants of wheat cultivar Karl 92 were subjected to regimes (day‐night) of 20–20, 25–20, 30–20, and 35–20°C from 10 and 15 days after anthesis (DAA) until ripeness, and 25–20, 30–20, and 35–20°C from 20 DAA until ripeness. In other experiments, plants of wheat cultivars Karl 92 and TAM 107 were dried at 20 and 40°C, and spikes of Karl 92 were dried at different temperature and humidity conditions to asses the effects on quality of high temperature and drying rates during grain ripening. Flour yield correlated positively with kernel weight and diameter, test weight, and proportion of large kernels. Flour yield decreased as temperature increased and correlated negatively with hardness index and proportion of small grains. High growth temperatures and rapid grain desiccation decreased mixing time and tolerance of the flours. The greatest damage occurred when high temperature was maintained continuously from early grain filling until ripeness. Weakening of dough properties by rapid desiccation during ripening suggest that temperature, humidity, and possibly soil moisture all contribute to the final quality of bread wheat. DA - 1998/// PY - 1998/// DO - 10.1094/CCHEM.1998.75.4.421 VL - 75 IS - 4 SP - 421-427 SN - 0009-0352 ER - TY - JOUR TI - Nitrate effect on carbon and nitrogen assimilating enzymes of maize hybrids representing seven eras of breeding AU - Purcino, A. A. C. AU - Arellano, C. AU - Athwal, G. S. AU - Huber, S. C. T2 - Maydica DA - 1998/// PY - 1998/// VL - 43 IS - 2 SP - 83-94 ER - TY - JOUR TI - Humic acid application affects photosynthesis, root development, and nutrient content of creeping bentgrass AU - Liu, C. H. AU - Cooper, R. J. AU - Bowman, D. C. T2 - HortScience DA - 1998/// PY - 1998/// VL - 33 IS - 6 SP - 1023-1025 ER - TY - JOUR TI - Effects of foliar insecticides on survival of northern bobwhite quail chicks AU - Palmer, WE AU - Puckett, KM AU - Anderson, , JR AU - Bromley, PT T2 - JOURNAL OF WILDLIFE MANAGEMENT AB - Reduced survival of chicks may result from exposure to insecticides and may explain declines in northern bobwhite quail (Colinus virginianus) populations on agricultural landscapes. To determine the risk insecticides pose to quail, we quantified exposure rates and hazard, Exposure rate depends on quail habitat use in relation to insecticide applications, whereas hazard depends on susceptibility to a toxin and the dose an individual receives, Because providing early-successional vegetation around row-crop fields is a typical habitat management recommendation, we determined rates of exposure of quail and their broods to insecticides applied to soybean fields with and without vegetated field borders, Radiocollared quail (n = 69) used soybean fields extensively (64% of telemetry locations) at the time of year insecticides were applied. Quail used soybean fields twice as often when vegetated borders surrounded crop fields (P = 0.04). Ten of 18 broods monitored by telemetry were located in soybean fields 88% of the time. In 1993. 4 of 6 broods 0.49). However, ChE activity was depressed (P < 0.001) and body mass was lower (P = 0.02) in chicks exposed to methyl parathion, which historically (pre-1980) received significant use in production of row crops in North Carolina. Our results, along with data on use and toxicity of other insecticides applied to row crops, collectively suggest direct affects to survival of quail chicks from use of foliar-applied insecticides does not explain reduced quail densities on agricultural landscapes. DA - 1998/10// PY - 1998/10// DO - 10.2307/3802023 VL - 62 IS - 4 SP - 1565-1573 SN - 1937-2817 KW - chick KW - cholinesterase KW - Colinus virginianus KW - habitat use KW - insecticides KW - methomyl KW - methyl parathion KW - northern bobwhite KW - quail KW - survival KW - thiodicarb ER - TY - JOUR TI - Deep soil moisture storage and transpiration in forests and pastures of seasonally-dry amazonia AU - Jipp, PH AU - Nepstad, DC AU - Cassel, DK AU - De Carvalho, CR T2 - CLIMATIC CHANGE DA - 1998/7// PY - 1998/7// DO - 10.1023/A:1005308930871 VL - 39 IS - 2-3 SP - 395-412 SN - 1573-1480 ER - TY - JOUR TI - Boron uptake and concentration in cotton and soybean as affected by boron source AU - Guertal, EA AU - Abaye, AO AU - Lippert, BM AU - Gascho, GJ AU - Miner, GS T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Continued introduction of new boron (B) fertilizer materials prompted a second examination of the efficacy of foliar‐applied B materials on B content, B uptake, and dry matter yield of cotton (Gossypium hirsutum L.) and soybean (Glycine max L.). Similar to a previous study, this greenhouse study was conducted at four participating universities using 6‐week‐old cotton (Deltapineland 90) and soybean (Pioneer 9761) plants. Sources and rates of B were 1) boric acid (17.5% B) at 0.22 kg ha‐1,2) sodium borate (Solubor® 20.5% B) at 0.22 kg ha‐1, 3) Smith & Ardussi Liquid B (10% B) at 0.22 kg ha‐1,4) Smith & Ardussi Liquid B at 0.11 kg ha‐1, 5) Borosol 10 (10% B) at 0.22 kg ha‐1, 6) Borosol 10 at 0.11 kg ha‐1, and 7) an untreated control. Control plants that did not receive B were sprayed with water. Four plants were grown in each 15‐cm diam. pot in sandy loam soil. Plants were sprayed at 6 weeks of growth and top growth was harvested at eight weeks. Whole‐plant samples were dried (70°C), ground, and analyzed for B content. Uptake of B, plant B concentration, and plant dry weight varied by state, so results were not combined over all states. In every state there were significant differences in B concentration and B uptake by cotton and soybean as affected by B treatment, but effects were not consistent with any one B source. In two of four cases (Alabama and Georgia) cotton plants receiving any B treatment had greater B concentration and B uptake than the water‐sprayed control. In Virginia and North Carolina, application of B treatments rarely affected B uptake by cotton or soybean. No one B source produced consistently greater B uptake than any other B source. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809370172 VL - 29 IS - 19-20 SP - 3007-3014 SN - 0010-3624 ER - TY - JOUR TI - Biological significance of divalent metal ion binding to 14-3-3 proteins in relationship to nitrate reductase inactivation AU - Athwal, GS AU - Huber, JL AU - Huber, SC T2 - PLANT AND CELL PHYSIOLOGY AB - In this report we address two questions regarding the regulation of phosphorylated nitrate reductase (pNR; EC 1.6.6.1) by 14-3-3 proteins. The first concerns the requirement for millimolar concentrations of a divalent cation in order to form the inactive pNR:14-3-3 complex at pH 7.5. The second concerns the reduced requirement for divalent cations at pH 6.5. In answering these questions we highlight a possible general mechanism involved in the regulation of 14-3-3 binding to target proteins. We show that divalent cations (e.g. Ca2+, Mg2+ and Mn2+) bind directly to 14-3-3s, and as a result cause a conformational change, manifested as an increase in surface hydrophobicity. A similar change is also obtained by decreasing the pH from pH 7.5 to pH 6.5, in the absence of divalent cations, and we propose that protonation of amino acid residues brings about a similar effect to metal ion binding. A possible regulatory mechanism, where the 14-3-3 protein has to be "primed" prior to binding a target protein, is discussed. DA - 1998/10// PY - 1998/10// DO - 10.1093/oxfordjournals.pcp.a029303 VL - 39 IS - 10 SP - 1065-1072 SN - 0032-0781 KW - 14-3-3 protein KW - conformational change KW - fluorescence KW - metal binding site KW - nitrate reductase KW - protonation ER - TY - JOUR TI - Zinc toxicity in soybean grown at high iron concentration in nutrient solution AU - Fontes, RLF AU - Cox, FR T2 - JOURNAL OF PLANT NUTRITION AB - Abstract Abstract Iron (Fe) deficiency in plants may be caused by heavy metal toxicity and is expressed mainly by chlorosis in young leaves. Zinc (Zn) is often the heavy metal involved. The growth of soybean (Glycine max [L.] Merr.) in a 40 μM Zn nutrient solution was studied using a factorial 2x2x2 experiment; two Fe (20 and 100 μM), two S (0.02 and 20 mM), and two Fe foliar fertilization (with and without Fe‐DTPA) levels. Lower dry matter yield, chlorosis in young leaves, and change in the periodic movement (light/dark) of unifoliate leaves were the main symptoms of Zn toxicity. Plants supplied with 100 μM Fe produced more dry matter than those supplied with 20 μM and did not show leaf chlorosis, but still showed a change in the periodic movement of the leaves. A high Fe supply prevented most of the detrimental effects of toxic Zn. There was no effect of sulfur (S) on plant symptoms, and foliar fertilization with Fe‐DTPA did not result in regreening of chlorotic leaves. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365517 VL - 21 IS - 8 SP - 1723-1730 SN - 0190-4167 ER - TY - JOUR TI - Temporal distribution of C-14 in soil water from field lysimeters treated with C-14-metolachlor AU - Keller, KE AU - Weber, JB AU - Cassel, DK AU - Wollum, AG AU - Miller, CT T2 - SOIL SCIENCE AB - In a previous study utilizing fallow field lysimeters of an undisturbed, loamy sand soil treated with 14C-metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide], 2 to 5% of the applied 14C was mobile to soil depths of 56 to 96 cm. The objective of this 120-day study was to determine the temporal distribution of 14C-metolachlor and/or metabolite(s) in soil water from similar field lysimeters and their possible contribution to groundwater contamination. Undisturbed soil column field lysimeters (20.3-cm i.d. × 101-cm long; 16 gauge steel) were driven into a conventionally tilled Dothan loamy sand (fine-loamy, siliceous, thermic Plinthic Kandiudult) and treated with 14C-metolachlor and tritiated water (3H2O) and subjected to natural rainfall or irrigation. Percent recovery of metolachlor and/or metabolite(s) in the soil, as based on 14C measurement, was 62% at 30 days, 63% at 60 days, 51% at 90 days, and 49% at 120 days. Recovery of 3H2O was 36, 24, 6 and 0.25% of the applied for the same time periods. By 30 and 60 days after application (DAA), 3H2O had distributed symmetrically in the soil profile, whereas, a large percentage of the 14C was retained in the upper 24 cm. No 14C and <1% of the applied 3H2O was recovered in leachate the first 30 days. Cumulative recovery of 14C in leachate was <1% of that applied at 60 days, 3% at 90 days, and 7% at 120 days. Cumulative recovery of 3H2O in leachate for the same time periods was 22, 39, and 39% of that applied. The symmetrical breakthrough curve for 3H2O indicated no preferential flow or immobile water, whereas the breakthrough curve for 14C was asymmetrical as a result of the sorption-desorption processes. Peak concentrations of 14C and 3H2O in the leachate occurred at 94 and 63 DAA, respectively. The sorptive tendencies of both radiolabeled species distinguished the magnitude of movement, with 3H2O much more mobile than 14C-metolachlor and/or metabolite(s). Assuming that all 14C in leachate was parent, average metolachlor concentrations in leachate were less than the National Health Advisory level, which may indicate that metolachlor should be considered a low risk chemical because of its potential to contaminate groundwater in soils with low organic matter and high clay content in the subsoil. DA - 1998/11// PY - 1998/11// DO - 10.1097/00010694-199811000-00004 VL - 163 IS - 11 SP - 872-882 SN - 1538-9243 KW - herbicide metabolites KW - herbicide volatilization KW - leaching KW - mobility index KW - tritiated water ER - TY - CONF TI - Soil hydraulic properties affected by various components of domestic wastewater AU - Amoozegar, A. AU - Niewoehner, C. P. C2 - 1998/// C3 - On-site wastewater treatment: Proceedings of the eighth national symposium on individual and small community sewage systems, March 8-10, 1998, Orlando, Florida CN - TD929 .N33 1998 DA - 1998/// SP - 155-166 PB - St. Joseph, Mich.: American Society of Agricultural Engineers ER - TY - JOUR TI - Selection response and developmental basis for early and late panicle emergence in Alamo switchgrass AU - Van Esbroeck, GA AU - Hussey, MA AU - Sanderson, MA T2 - CROP SCIENCE AB - For many determinate crop species, delayed flowering, associated with the production of more mainstem leaves and/or a reduced rate of leaf appearance, extends the vegetative phase and results in higher biomass yields. Studies were carried out on ‘Alamo’ switchgrass (Panicum virgatum L.), a potential biofuel crop, to determine the realized heritability and developmental basis for variation in the time to panicle emergence. A single cycle of divergent selection for time of panicle emergence (earliest and latest 3%) was carried out. Time panicle emergence for the parent and progeny generation was evaluated in the field for 2 yr and 1 yr in a greenhouse trial. For the parental generation, leaf emergence was monitored weekly and final leaf numbers were recorded. Panicle emergence for the selected early and late parents differed by an average of 22 d (10 d earlier and 12 d later than the original population). Realized heritabilities in the year following establishment were 1.0 and 0.92 for early and late panicle emergence, respectively. The early and late parent plants initiated growth at the same time in spring and produced leaves at the same rate; however, late plants produced from 0.7 to 2.1 more mainstem leaves than early plants. Similar leaf appearance rates, combined with higher final leaf numbers on late than on early plants, strongly suggested that late panicle emergence resulted from delayed floral initiation. This study showed that there is considerable genetic variation for flowering time in Alamo switchgrass and that the extended period of vegetative growth in late flowering types was associated with the production of more leaves. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020010x VL - 38 IS - 2 SP - 342-346 SN - 0011-183X ER - TY - JOUR TI - Roasted peanut flavor and related compositional characteristics of peanut kernels of spring and fall crops grown in Taiwan AU - Ku, KL AU - Lee, RS AU - Young, CT AU - Chiou, RYY T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - Spring and Fall crops of peanut are grown each year in Taiwan. A general consumer concept indicating that the roasted peanut flavor of the kernels of the former is inferior to the latter deserves further investigation. Tainan 11 and Tainan 12 (Spanish cultivars) were consecutively grown for two crops in an experimental field with green pea for rotation and harvested 70 days after flowering. In compositional analyses of the sound and mature kernels, the ratio of the contents of typical and atypical flavor precursors of free amino acids (T:AT) was higher while the sucrose content was lower in the kernels of Fall crops than those of Spring crops. In headspace analysis, the total volatile content varied insignificantly while the sulfur volatile content was higher in the kernels of Spring crops. When the kernels were roasted and subjected to peanut oil and flavor extraction and GC-MS analysis of the pyrazine compounds, the contents of the total pyrazines and most of the peanut flavor-related pyrazines were higher in the kernels of Fall crops than those of Spring crops. Keywords: Peanut; peanut flavor; growing season; free amino acid; headspace analysis; pyrazine; GC-MS DA - 1998/8// PY - 1998/8// DO - 10.1021/jf980134k VL - 46 IS - 8 SP - 3220-3224 SN - 0021-8561 KW - peanut KW - peanut flavor KW - growing season KW - free amino acid KW - headspace analysis KW - pyrazine KW - GC-MS ER - TY - JOUR TI - Response of four rice (Oryza sativa) cultivars to triclopyr AU - Jordan, DL AU - Sanders, DE AU - Linscombe, SD AU - Williams, BJ T2 - WEED TECHNOLOGY AB - Experiments were conducted from 1994 through 1996 to determine the response of the rice cultivars ‘Bengal,’ ‘Cypress,’ ‘Jodon,’ and ‘Kaybonnet’ to triclopyr at 0.42 (standard rate) and 0.84 kg ai/ha applied postemergence at the four-leaf and panicle initiation stages of growth. Applications at the four-leaf stage were made in close association with fertilization and flood establishment, which often increases the potential for triclopyr to injure rice. Visible injury from triclopyr was slightly higher for the cultivar Jodon than for the cultivars Bengal, Cypress, or Kaybonnet. Injury was 3% or less when triclopyr at 0.42 kg/ha was applied at panicle initiation regardless of the cultivar. Triclopyr at 0.42 and 0.84 kg/ha applied at the four-leaf growth stage injured rice 7% and 22%, respectively. Triclopyr at 0.84 kg/ha applied at the four-leaf stage of growth delayed days from seedling emergence to seed head emergence and rice grain yield, irrespective of cultivar. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00043773 VL - 12 IS - 2 SP - 254-257 SN - 0890-037X KW - triclopyr, [(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid KW - rice, Oryza sativa L. 'Bengal', 'Cypress', 'Kaybonnet' KW - crop injury KW - herbicide tolerance ER - TY - JOUR TI - Phenylpropanoid metabolism and phenolic composition of soybean [Glycine max (L.) Merr.] leaves following exposure to ozone AU - Booker, FL AU - Miller, JE T2 - JOURNAL OF EXPERIMENTAL BOTANY AB - Plants treated with the air pollutant, ozone (O3), often respond with increased transcript levels and activities of enzymes in the general phenylpropanoid and lignin pathways. This suggests that increased biosynthesis of lignin and related products also occurs. The purpose of this study was to determine whether O3 stimulated enzyme activities in these pathways in soybean [Glycine max (L.) Merr.] leaves, and if so, were hydroxycinnamic acids, lignin and suberin also produced. Plants were grown for 6 weeks in charcoal-filtered (CF) air and then treated with either CF air or CF air plus 100 nmol O3 mol−-1 7 h daily for up to 13 d in chambers in the greenhouse or in open-top chambers in the field. In greenhouse experiments, the activities of general phenylpropanoid pathway enzymes (phenylalanine ammonia-lyase and 4-coumarate:CoA ligase) were stimulated by O3 after 6 h. The activity of an enzyme in the lignin pathway (cinnamyl alcohol dehydrogenase) increased in O3-treated plants after 27 h. In greenhouse and field experiments, levels of cell-wall-bound total phenolics, acid-insoluble lignin and lignothioglycolic acid (LTGA) extracted from leaf tissue from O3-treated plants increased on average by 65%. However, histochemistry, UV and IR spectra, radiolabelling and a nitrobenzene oxidation assay all indicated that lignin and suberin did not increase with O3 treatment. Acidinsoluble lignin and LTGA extracted from O3-treated plants probably contained phenolic polymers that form in wounded or senescent tissues, thereby causing overestimates of the changes. Ozone-induced increases in phenolic metabolism, resembling certain elicited defence responses, thus occurred in concert with effects characteristic of the browning reaction and wound responses. DA - 1998/7// PY - 1998/7// DO - 10.1093/jexbot/49.324.1191 VL - 49 IS - 324 SP - 1191-1202 SN - 1460-2431 KW - phenolics KW - lignin KW - ozone KW - soybean KW - air pollution ER - TY - CONF TI - Performance of sand lined trench and conventional systems within a management entity AU - Lindbo, D. L. AU - Campbell, T. M. AU - Deal, N. AU - Hollowell, R. C2 - 1998/// C3 - On-site wastewater treatment: Proceedings of the eighth national symposium on individual and small community sewage systems, March 8-10, 1998, Orlando, Florida CN - TD929 .N33 1998 DA - 1998/// SP - 177-185 PB - St. Joseph, Mich.: American Society of Agricultural Engineers ER - TY - CONF TI - Performance of an on-site wastewater disposal system in a slowly permeable soil AU - Weymann, D. F. AU - Amoozegar, A. AU - Hoover, M. T. C2 - 1998/// C3 - On-site wastewater treatment: Proceedings of the eighth national symposium on individual and small community sewage systems, March 8-10, 1998, Orlando, Florida CN - TD929 .N33 1998 DA - 1998/// SP - 134-145 PB - St. Joseph, Mich.: American Society of Agricultural Engineers ER - TY - JOUR TI - Iron deficiency and zinc toxicity in soybean grown in nutrient solution with different levels of sulfur AU - Fontes, RLF AU - Cox, FR T2 - JOURNAL OF PLANT NUTRITION AB - Abstract A typical symptom of iron (Fe) deficiency in plants is yellowing or chlorosis of leaves. Heavy metal toxicity, including that of zinc (Zn), is often also expressed by chlorosis and may be called Fe chlorosis. Iron deficiency and Zn toxicity were evaluated in soybean (Glycine max [L.] Merr.) at two levels each of Zn (0.8 and 40 μM), Fe (0 and 20 μM), and sulfur (S) (0.02 and 20 mM). Reduction in dry matter yield and leaf chlorosis were observed in plants grown under the high level of Zn (toxic level), as well as in the absence of Fe. Zinc toxicity, lack of Fe, and the combination of these conditions reduced dry matter yield to the same extent when compared to the yield of the control plants. The symptoms of Zn toxicity were chlorosis in the trifoliate leaves and a lack of change in the orientation of unifoliate leaves when exposed to light. The main symptoms of Fe deficiency were chlorosis in the whole shoot and brown spots and flaccid areas in the leaves. The latter symptom did not appear in plants grown with Fe but under Zn toxicity. It seems that Fe deficiency is a major factor impairing the growth of plants exposed to high levels of Zn. Under Zn toxicity, Fe and Zn translocation from roots to shoots increased as the S supply to the plants was increased. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365516 VL - 21 IS - 8 SP - 1715-1722 SN - 0190-4167 ER - TY - JOUR TI - Herbicide rate recommendations: Soil parameter equations vs. registered rate recommendations AU - Gonese, JU AU - Weber, JB T2 - WEED TECHNOLOGY AB - Chlorimuron, clomazone, imazaquin, imazethapyr, and pendimethalin were each applied at five rates to soils at 10 different sites each year for three years to determine which soil properties influenced their bioactivity. Six soils in the U.S. (NC) and four in Zimbabwe were characterized for their plow-layer contents of organic matter (OM), humic matter (HM), clay mineral (CM), and silt and for pH and cation exchange capacity (CEC). At each site, the rate of each herbicide yielding 80% weed control (I 80 ) was determined by visually evaluating the treated plots. The I 80 values were then regressed with the various soil properties to determine which of them contributed to this rate. In the U.S. soils, the I 80 was highly correlated with % OM ( r 2 = 0.64–0.72) and % HM ( r 2 = 0.55–0.69) for chlorimuron, imazaquin, and pendimethalin but was less correlated with % OM ( r 2 = 0.30) and pH ( r 2 = 0.31) for imazethapyr. Equations relating the herbicide rate for 100% weed control to soil properties were derived for chlorimuron, imazaquin, imazethapyr, and pendimethalin then compared with registered recommended rates for each chemical from the label. Herbicide rate equations based on similar soil parameters were taken from the literature to compare with our rate equations and with registered rate recommendations for comparison purposes and to add validity to the use of soil parameters for making herbicide rate recommendations. The rate equations, based on selected soil parameters, produced rates comparable with registered rates for chlorimuron, pendimethalin, and metribuzin and lower rates of application than registered rates for imazaquin, imazethapyr, alachlor, and metolachlor for soils with OM levels below 3.5%. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00043748 VL - 12 IS - 2 SP - 235-242 SN - 1550-2740 KW - chlorimuron, 2[[[[(4-chloro-6-methoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]benzoic acid KW - clomazone, 2-[(2-chlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone KW - imazaquin, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylic acid KW - imazethapyr, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid KW - pendimethalin, N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine KW - herbicide bioactivity, herbicide inactivation, barnyardgrass, Echinochloa crusgalli (L.) Beauv. #(3) ECHCG KW - prickly sida, Sida spinosa L. # SIDSP KW - green foxtail, Setaria viridus (L.) Beauv. # SETVI KW - velvetleaf, Abutilon theophrasti Medik. # ABUTH KW - goosegrass, Eleusine indica (L.) Gaertn. # ELEIN KW - crowfootgrass, Dactyloctenium aegyptium (L.) Willd. # DTTAE KW - bristly starbur, Acanthosperum hispidium DC. # ACNHI KW - Florida pusley, Richardia scabra L. # RCHSC KW - jimsonweed, Datura stramonium L. # DATST KW - redroot pigweed, Amaranthus retroflexus L. # AMARE KW - large crabgrass, Digitaria sanguinalis (L.) Scop. # DIGSA KW - common ragweed, Ambrosia artemisiifolia L. # AMBEL KW - common lambsquarters, Chenopodium album L. # CHEAL KW - foxtail spp. Setaria spp. # SET KW - soybean, Glycine max (L.) Merr. ER - TY - JOUR TI - Genetic variation for modifiers controlling reduced saturated fatty acid content in soybean AU - Rebetzke, GJ AU - Burton, JW AU - Carter, TE AU - Wilson, RF T2 - CROP SCIENCE AB - Soybean [Glycine max (L.) Merr.] oils with reduced palmitic acid concentrations should comply with U.S. Food and Drug Administration (FDA) regulations for vegetable oils with lower saturated fatty acid contents. This study was designed to investigate the genetic basis for reduced palmitic and stearic acid contents in the seed oil of reduced palmitic acid germplasm, N87-2122-4. Crosses between N87-2122-4 and Midwest-adapted cultivars, Kenwood and P9273, revealed frequencies of reduced and normal palmitic acid among F2 progeny consistent with segregation at a single major locus. There was a large phenotypic variation (15–30 g kg−1) for paimitic acid content measured on progeny homozygous for either reduced or normal palmitic acid alleles, however. Repeatability of this variation was examined in 87 reduced and normal palmitic F5:7 lines randomly sampled from each cross. Reduced palmitic acid lines ranged between 54 and 72 g kg−1, and normal palmitic acid lines between 90 and 119 g kg−1 for both crosses. No line produced significantly less palmitic acid than N87-2122-4 but ≈ 55% of the reduced palmitic acid lines were significantly greater (P < 0.01). The large genotypic ranges observed for both F2 and F5:7 generations may be explained by an undetermined number of genetic modifiers associated with the major palmitic acid locus. Across both populations, the major reduced palmitic acid allele was associated with a 15% reduction in stearic acid content. However, genetic correlations for palmitic and stearic acid contents among lines homozygous for the major palmitic acid alleles were nonsignificant (rg = −0.30–0.18), enabling simultaneous selection of inbred lines producing both reduced palmitic and stearic acid contents. High narrow-sense heritabilities (>80%) for palmitic and stearic acid contents suggest that total saturates may be reduced by selection in few environments for major and modifier genes controlling reduced palmitic acid content. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020004x VL - 38 IS - 2 SP - 303-308 SN - 0011-183X ER - TY - JOUR TI - Field evaluation of calcium sulfate as a chemical flocculant for sedimentation basins AU - Przepiora, A AU - Hesterberg, D AU - Parsons, JE AU - Gilliam, JW AU - Cassel, DK AU - Faircloth, W T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Abstract Sedimentation basins are built at construction sites to reduce the load of suspended solids in runoff water discharged into surface waters. However, these basins are not effective in reducing turbidity caused by fine suspended particles such as clay and silt. The objective of this field study was to evaluate the efficiency of moulding plaster (CaSO 4 · 0.5 H 2 O) as a chemical flocculant for reducing the turbidity of water discharged from sedimentation basins equipped with a floating skimmer device. Following each of 14 rainfall events, sedimentation basins at two urban construction sites were either treated with moulding plaster or left untreated, and the turbidity and chemical properties of the impounded water and discharge water were monitored as the basins drained during a 50‐ to 70‐h time period. Each sedimentation basin was equipped with a floating skimmer device that discharged water at a controlled rate from 5‐cm below the surface of the impounded water. The turbidity of discharge water from untreated basins ranged from 100 to 1650 NTU (nephelometric turbidity units), while a surface‐applied moulding plaster treatment of 450 to 520 mg L −1 decreased the turbidity to <50 NTU. The time required for the discharge water from treated basins to reach either 100 NTU (2–20 h) or 50 NTU (5–52 h) was inversely proportional to the concentration of dissolved moulding plaster. Chemical flocculation using moulding plaster reduced the turbidity of discharge water to <50 NTU while producing dissolved SO 4 concentrations of <250 mg L −1 . DA - 1998/// PY - 1998/// DO - 10.2134/jeq1998.00472425002700030026x VL - 27 IS - 3 SP - 669-678 SN - 0047-2425 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032076630&partnerID=MN8TOARS ER - TY - JOUR TI - Combined effects of chronic ozone and elevated CO2 on Rubisco activity and leaf components in soybean (Glycine max) AU - Reid, CD AU - Fiscus, EL AU - Burkey, KO T2 - JOURNAL OF EXPERIMENTAL BOTANY DA - 1998/12// PY - 1998/12// DO - 10.1093/jexbot/49.329.1999 VL - 49 IS - 329 SP - 1999-2011 SN - 1460-2431 KW - O-3 x CO2 interaction KW - carbohydrate metabolism KW - Rubisco KW - sugars KW - non-structural carbohydrates ER - TY - JOUR TI - Changes in agronomic and seed characteristics with selection for reduced palmitic acid content in soybean AU - Rebetzke, GJ AU - Burton, JW AU - Carter, TE AU - Wilson, RF T2 - CROP SCIENCE AB - Development of soybean [Glycine max (L.) Merr.] cultivars with reduced saturated fatty acid content is an important goal of soybean breeders. The objective of this study was to determine if genes for reduced palmitic acid content in the fatty acid germplasm N87-2122-4 were associated with changes in agronomic and seed quality characteristics. Approximately 22 reduced (54–72 g kg−1) and 22 normal (90–119 g kg−1) palmitic acid F5:7 lines were sampled from each of two crosses, N87-2122-4 × ‘Kenwood’ and N87-2122-4 × ‘P9273’ and grown in replicated tests at four North Carolina locations. Lines homozygous for the major reduced palmitic acid gene produced significantly (P < 0.01) less (=10%) seed yield than lines homozygous for the normal gene. Furthermore, selection differentials for the normal palmitic acid populations were significantly (P < 0.01) larger than for the reduced palmitic acid population. Oleic and linolenic acid contents were significantly (P < 0.01) greater for reduced palmitic acid lines, while the major reduced palmitic acid gene had no significant (P > 0.05) effect on linoleic and seed protein contents. Seed oil content was significantly (P < 0.05) greater among reduced palmitic acid lines in the N87- 2122-4 × Kenwood cross only. Genetic correlations were estimated among lines to examine the influence of selection for palmitic acid genetic modifiers on agronomic traits. Palmitic acid content was significantly (P < 0.05) and negatively correlated with changes in oleic acid, and significantly (P < 0.05) and positively correlated with changes linolenic acid contents. Genetic modifiers conditioning palmitic acid content seemed independent of genes controlling seed yield, suggesting that selection for reduced palmitic acid content among lines homozygous for the reduced palmitic acid gene may be achieved without a reduction in seed yield. Efforts to further reduce palmitic acid content in populations fixed for the major palmitic acid gene should improve the quality of soybean oils produced for food processing markets. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020003x VL - 38 IS - 2 SP - 297-302 SN - 1435-0653 ER - TY - JOUR TI - Base temperature and heat unit requirement of 49 Mexican maize races AU - Ruiz, J. A. AU - Sanchez, J. J. AU - Goodman, M. M. T2 - Maydica DA - 1998/// PY - 1998/// VL - 43 IS - 4 SP - 277-282 ER - TY - JOUR TI - 3-hydroxy-3-methylglutaryl-coenzyme a reductase kinase and sucrose-phosphate synthase kinase activities in cauliflower florets: Ca2+ dependence and substrate specificities AU - Toroser, D AU - Huber, SC T2 - ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS AB - Plant 3-hydroxy-3-methylglutaryl-CoA reductase(HMGR; EC 1.1.1.34) and sucrose–phosphate synthase (SPS; EC 2.4.1.14) and synthetic peptides designed from the known phosphorylation sites of plant HMGR (SAMS*: KSHMKYNRSTKDVK), rat acetyl-CoA carboxylase (SAMS: HMRSAMSGLHLVKRR), spinach SPS (SP2: GRRJRRISSVEJJDKK), and spinach NADH:nitrate reductase (NR6: GPTLKRTASTPFJNTTSK) were used to characterize kinase activities from cauliflower (Brassica oleraceaL.) inflorescences. The three major peaks of protein kinase activity resolved by anion-exchange FPLC are homologs of those observed previously in spinach leaves and thus are designated PKI, PKIV, and PKIII, listed in order of elution. PKIVwas the most active in terms of phosphorylation and inactivation of recombinantNicotianaHMGR and was also strictly Ca2+dependent. The novel aspects are that PKIIIhas not been detected in previous cauliflower studies, that SAMS* is a more specific peptide substrate to identify potential HMGR kinases, and that the major HMGR kinase in cauliflower is Ca2+dependent. Of the three major kinases that phosphorylated the SP2 peptide only PKI(partially Ca2+sensitive) and PKIII(Ca2+insensitive) inactivated native spinach leaf SPS. Cauliflower extracts contained endogenous SPS that was inactivated by endogenous kinase(s) in an ATP-dependent manner and this may be one of the substrate target proteins for PKIand/or PKIII. The substrate specificity of the three kinase peaks was studied using synthetic peptide variants of the SP2 sequence. All three kinases had a strong preference for peptides with a basic residue at P-6 (as in SP2 and SAMS*; SAMS has a free amino terminus at this position) or a Pro at P-7 (as in NR6). This requirement for certain residues at P-6 or P-7 was not recognized in earlier studies but appears to be a general requirement. In plant HMGR, a conserved His residue at P-6 is involved directly in catalysis and this may explain why substrates reduced HMGR phosphorylationin vitro. DA - 1998/7/15/ PY - 1998/7/15/ DO - 10.1006/abbi.1998.0740 VL - 355 IS - 2 SP - 291-300 SN - 0003-9861 KW - protein kinase KW - 3-hydroxy-3-methylglutaryl-CoA reductase KW - Brassica oleracea KW - sucrose-phosphate synthase KW - phosphorylation motif ER - TY - JOUR TI - Winter annual small grain forage potential. I. Dry matter yield in relation to morphological characteristics of four small grain species at six growth stages AU - Edmisten, KL AU - Green, JT AU - Mueller, JP AU - Burns, JC T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Small grains offer a potential animal feed at a time when moisture is usually available in the Southeast. The four major winter annual small grains, barley, oats, rye, and wheat, have not been compared as potential feed sources in the same study in the past. These four small grains were harvested at six stages of growth: vegetative, boot, heading, milk, soft dough, and hard dough. Harvest dates, dry matter (DM) yield, DM yield of regrowth following initial harvest, DM concentration, and the proportions of leaf, stem and inflorescence were measured and used to evaluate the four species for silage production and grazing potential. Rye and barley reached boot prior to the suggested planting date for corn in the Piedmont of North Carolina and dry matter yields ranged from 4.72 to 6.71 Mg ha‐1 and were harvested. Barley reached milk, soft dough, and hard dough earlier than the other species and was equal to or higher than the other species in proportion of DM in leaf DM yield and total DM yield in 1982 and 1983. Wheat DM yield was second to barley from heading to hard dough in 1982 and 1983. Barley DM yield was 69 to 80% of wheat from boot through soft dough in 1984. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809369992 VL - 29 IS - 7-8 SP - 867-879 SN - 1532-2416 ER - TY - JOUR TI - Variability associated with testing shelled corn for fumonisin AU - Whitaker, T. B. AU - Trucksess, M. W. AU - Johansson, A. S. AU - Giesbrecht, F. G. AU - Hagler, W. M. AU - Bowman, D. T. T2 - Journal of AOAC International DA - 1998/// PY - 1998/// VL - 81 IS - 6 SP - 1162-1168 ER - TY - JOUR TI - Using crop performance data to select hybrids and varieties AU - Bowman, DT T2 - JOURNAL OF PRODUCTION AGRICULTURE AB - The proliferation of hybrids and varieties available to growers and the availability of data in various formats make varietal selection difficult. This report seeks to guide growers, consultants, and extension agents on how to use the most appropriate data sets from university trials in varietal selection. Six crops (barley [Hordeum vulgare L.], corn [Zeu mays L], cotton [Gossypium hirsutum L], oats [Avena sativa L.], soybean [Glycine max (L.) Merr.], and wheat [Triticum aestivum L.]) in the North Carolina Official Variety Trials were examined for turnover rate, variety × environmental interactions, and probabilities of predicting the top varieties in a subsequent year based on single and 2-yr data. Single-year turnover rates ranged from 27 to 51%. There were no variety × location interactions but there were variety × year interactions in barley and early and medium maturing cotton, and variety × location × year interactions in barley, MGVI soybean, and wheat. Based on all data examined in this study, single-year multi-location data would be appropriate to use in selecting midseason corn hybrids. Two-year multi-location data would be useful for barley, early and full-season corn, early and medium cotton, oats, MG V and VI soybean, and wheat. The protocol used in this study could be applied to other crops in other states recognizing that not all crops are tested equally and best data sets may be different for the various crops. Research Question University-run state crop performance trials provide unbiased information for growers, consultants, extension agents, and seed company representatives to use in making varietal selection decisions. The trials include many entries from several different companies or public institutions and are located at several sites in each state. This vast data set serves to confuse the grower and agricultural professional; they have to know the most helpful data to use in their varietal selection process. Literature Summary In Missouri and North Dakota, 2-yr multi-location means were found to be best for choosing corn hybrids. Multi-location data were the best predictors of future performance of soybean varieties in Minnesota. Private seed companies are advising that crop performance data be explained and presented in a manner that aids in interpreting the data. Study Description Six crops from the North Carolina Official Variety Trials were examined for turnover rate, significant interactions, and predictability. Ten years of data were available for barley, corn, oats, soybean, and wheat while 8 yr of data were available for cotton. The percentage of new varieties or turnover rate was determined for each year and every 2 yr. The probability of choosing high-yielding varieties or the top variety was determined from three different data sets. Applied Questions How often are new varieties entered in the crop performance trials and what are the ramifications? The turnover rate ranged from 51% of the early-season corn hybrids to only 27% of the barley varieties each year. Every 2 yr, 71% of the corn hybrids are new and only 40% of the barley varieties are new. Therefore for crops like the early-season corn hybrids, choosing hybrids from 3- and 4-yr data sets would mean some of the newer and possibly higher-yielding corn hybrids on the market would be ignored. What interactions are important and what impact will they have on interpreting that data? There were no variety × location interactions for any of the six crops, suggesting that multi-location data can be used. Variety × year interactions occurred with barley and cotton, indicating a need to use a minimum of 2-yr data. The three-way interaction (variety × location × year) was important for barley, MG VI soybean, and wheat; this would suggest the use of multi-location multi-year data. For what crops can we use single-year multi-location data to choose varieties or hybrids? These data proved adequate for mid-season corn hybrids. Which crops require multi-location 2-yr data for the best predictions and how predictive are they? Barley, early- and full-season corn hybrids, cotton, oats, MG V and VI soybean, and wheat all require 2-yr multi-location data. Predictions ran from 0.54 for medium-maturing cotton varieties to 0.94 for full-season corn hybrids for choosing the high-yielding entries. Recommendation The conclusions reached in this research pertain to North Carolina, but the principles are applicable to other states and regions. This approach should be followed whenever crop performance data are published so that growers and agricultural professionals can more efficiently select hybrids and varieties for their particular operation. DA - 1998/// PY - 1998/// DO - 10.2134/jpa1998.0256 VL - 11 IS - 2 SP - 256-259 SN - 0890-8524 ER - TY - JOUR TI - Root architecture affects nitrate leaching from bentgrass turf AU - Bowman, DC AU - Devitt, DA AU - Engelke, MC AU - Rufty, TW T2 - CROP SCIENCE AB - Understanding the determinants of nitrate leaching should improve nitrogen uptake efficiency and reduce ground water contamination. This column lysimeter study examined the effect of root architecture on NO 3 leaching from two genotypes of creeping bentgrass ( Agrostis palustris Huds.) differing in rooting characteristics. Ammonium nitrate was applied (50 kg N ha −1 ) and the columns were irrigated with 1, 2 or 3 cm day −1 (Exp. 1) or irrigation was delayed 1, 3 or 5 d (Exp. 2). In Exp. 1, leachate NO 3 concentrations and total N leached from the shallow‐rooted (SR) genotype were approximately twice those from the deep‐rooted (DR) genotype. An average of 38 and 18% of the applied N leached from the SR and DR genotypes, respectively. Cumulative leaching losses increased with irrigation depth. In Exp. 2, NO 3 leaching was reduced 90% or more by increasing the time period for immobilization from 1 to 5 d. Recovery of applied 15 N in the tissue averaged 87% after 2 mo. Absorption of NO 3 and NH 4 was measured in nutrient solution culture. The SR genotype had significantly higher uptake rates than DR for both forms of N, expressed on a root weight basis. Collectively these data indicate that a deep‐rooted turfgrass absorbs N more efficiently than a shallowrooted turf, reducing the concentration and total amount of NO 3 leached. The effect is apparently not due to differences in N uptake, but rather to rooting patterns. Environmental conditions and management practices that affect rooting depth and density may thus affect N nutrition and NO 3 leaching. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800060036x VL - 38 IS - 6 SP - 1633-1639 SN - 0011-183X ER - TY - JOUR TI - Role of foliar phenolics in host plant resistance of Malus taxa to adult Japanese beetles AU - Fulcher, A. F. AU - Ranney, T. G. AU - Burton, J. D. AU - Walgenbach, J. F. AU - Danehower, D. A. T2 - HortScience DA - 1998/// PY - 1998/// VL - 33 IS - 5 SP - 862-865 ER - TY - JOUR TI - Influence of humic substances on rooting and nutrient content of creeping bentgrass AU - Cooper, RJ AU - Liu, CH AU - Cooper, RJ T2 - CROP SCIENCE AB - Two greenhouse experiments were conducted to determine if application of humic substances to creeping bentgrass ( Agrostis stolonifera L.) turf would improve root mass, root length, or nutrient uptake. A commercially mined granular humate, a commercial liquid humic acid (HA), and liquid HAs extracted from leonardite, peat, and soil were applied to creeping bentgrass growing in either sand or solution culture and maintained at a height of 6 mm. Foliar applications included monthly or biweekly applications of HAs at 0, 100, 200, or 400 mg HA L −1 . In sand culture, humate incorporated to a depth of 10 cm stimulated a 45% increase in root mass at the 0‐ to 10‐cm depth and a 38% increase in root mass at the 10‐ to 20‐cm depth compared with the control. Incorporation of granular humate increased maximum root length 15% compared with non‐treated turf in sand culture. No foliar applied HA source consistently provided rooting superior to the control in either sand or solution culture. Nitrogen, Ca, Mg, and Fe uptake were relatively unaffected by humic substance application. The phosphorous concentration of plants in sand culture was increased 3 to 5% by incorporated humate and foliar application of soil, peat, or Leonardite‐derived HA. In solution culture, however, P uptake was unaffected by HA application. The lack of improved rooting or increased P uptake in solution culture supports the hypothesis that humic acids may have limited growth promoting effects on plants adequately supplied with nutrients. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800060037x VL - 38 IS - 6 SP - 1639-1644 SN - 1435-0653 ER - TY - JOUR TI - GLEAMS simulation of groundwater nitrate-N from row crop and swine wastewater spray fields in the eastern coastal plain AU - Stone, K. C. AU - Hunt, P. G. AU - Johnson, M. H. AU - Coffey, S. W. T2 - Transactions of the ASAE AB - Nonpoint source pollution of surface and groundwater resulting from agricultural management practices is amajor water quality problem. This problem was assessed on a demonstration watershed in the Cape Fear River Basin of North Carolina, during a five-year study. Groundwater was monitored in a row crop field (corn/wheat/soybean) and a swine waste spray field (Coastal bermuda grass). Groundwater nitrate-N concentrations averaged 6.5 mg/L in the row crop field. Nitrate-N concentrations in groundwater at the swine waste spray field exceeded 80 mg/L. Nitrate-N concentrations were simulated in both fields with the GLEAMS model. The GLEAMS model simulated groundwater nitrate-N concentrations with mean residuals (simulated-observed) 1.3 mg/L and 19 mg/L, respectively, for the row crop and the swine waste spray field. Groundwater nitrate-N concentrations have been reduced in the spray field by using improved management practices and the GLEAMS model simulated this nitrate-N concentration reduction. These simulation results show that the GLEAMS model can be used to predict nitrate-N loading of groundwater of these agricultural management systems. DA - 1998/// PY - 1998/// DO - 10.13031/2013.17156 VL - 41 IS - 1 SP - 51-57 ER - TY - JOUR TI - Fractionation and characterization of a protein fraction producing off-flavor volatiles in peanut seed AU - Basha, SM AU - Ying, M AU - Vives, MR AU - Young, CT AU - Boyd, LC T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - A high molecular weight protein fraction (peak I) obtained from peanut (Arachis hypogaea L. cv. Florunner) seed was fractionated using ammonium sulfate and methanol to isolate the protein(s) involved in off-flavor volatile production during roasting of peanut. The results showed that maximum off-flavor volatile-producing activity is associated with the 20% ammonium sulfate precipitate and 85% methanol-soluble fraction of this protein. Peak I protein was found to be lipoprotein in nature and is rich in oleic acid (63%) and palmetic acid (8%). Furthermore, the 85% methanol-soluble fraction of peak I protein was found to contain a mixture of low molecular weight proteins and major amounts of glycine (11%), alanine (11%), proline (15%), phenylalanine (8%), and lysine (8%). Keywords: Amino acids; electrophoresis; fatty acids; fractionation; lipoprotein; off-flavor; peanut; protein DA - 1998/6// PY - 1998/6// DO - 10.1021/jf971068+ VL - 46 IS - 6 SP - 2130-2135 SN - 0021-8561 KW - amino acids KW - electrophoresis KW - fatty acids KW - fractionation KW - lipoprotein KW - off-flavor KW - peanut KW - protein ER - TY - JOUR TI - Barley yellow dwarf virus: effects on carbohydrate metabolism in oat (Avena sativa) during cold hardening AU - Livingston, DP AU - Gildow, FE AU - Liu, SY T2 - NEW PHYTOLOGIST AB - Barley yellow dwarf virus (BYDV) causes significant losses in yield and in overwintering ability of winter cereals. Mechanisms by which the physiology of plants is affected by the virus are not clear. To see how carbohydrates in the crown of winter cereals were affected by BYDV, fructan isomers of degree of polymerization (DP) 3–5, fructan DP>6 and the simple sugars, glucose, fructose and sucrose, were measured before and during cold hardening in three oat ( Avena sativa L.) cultivars, ‘Wintok’, ‘Coast Black’ and ‘Fulghum’. On a fresh weight basis fructan DP>6 decreased by 50% in infected ‘Wintok’ and ‘Coast Black’ and by 25% in ‘Fulghum’. Two DP3, one DP4 and one DP5 isomer were significantly higher than non‐infected controls. The percentages of simple sugars in infected crowns were significantly higher than controls in all three cultivars in every week except the first week of hardening. Crude enzyme extracts from BYDV infected plants incubated with sucrose suggested higher invertase and lower sucrose‐sucrosyl transferase activity. When incubated with 1‐kestose and neokestin, no significant difference was found in fructose fructosyl transferase or in hydrolase activity. The activity of unidentified enzymes catalysing the synthesis of larger (DP>5) fructan was altered by BYDV. The decrease of carbohydrates in the crown induced indirectly by BYDV may alter the plant's capacity to regenerate tillers in the spring. The ability of plants to prevent or tolerate carbohydrate fluctuations induced by BYDV infection may be an important genetically regulated characteristic for developing virus‐resistant cultivars. DA - 1998/12// PY - 1998/12// DO - 10.1046/j.1469-8137.1998.00308.x VL - 140 IS - 4 SP - 699-707 SN - 0028-646X KW - barley yellow dwarf virus KW - carbohydrate metabolism KW - cold hardening KW - Avena sativa L. (oat) KW - fructans ER - TY - CONF TI - A risk-based approach to on-site system siting, design and management AU - Hoover, M. T. AU - Arenovski, A. AU - Daly, D. AU - Lindbo, D. C2 - 1998/// C3 - On-site wastewater treatment: Proceedings of the eighth national symposium on individual and small community sewage systems, March 8-10, 1998, Orlando, Florida CN - TD929 .N33 1998 DA - 1998/// SP - 66-78 PB - St. Joseph, Mich.: American Society of Agricultural Engineers ER - TY - JOUR TI - Winter annual small grain forage potential. II. Quantification of nutritive characteristics of four small grain species at six growth stages AU - Edmisten, KL AU - Green, JT AU - Mueller, JP AU - Burns, JC T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Four small grain species, barley, oat, rye, and wheat were harvested at six growth stages to investigate their nutritive quality as a possible replacement for corn silage. Crude protein (CP), in vitro dry matter disappearance (IVDMD), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents were measured on fresh and ensiled samples. The IVDMD, an estimate of forage ruminant digestibility, of all species generally decreased from the vegetative (765–854 g kg‐1) through the milk stage (505–662 g kg‐1) and then remained unchanged or increased slightly through hard dough with the exception of oats which often decreased during later stages of growth. The IVDMD of rye was usually lower than the other species from the milk to hard dough stage. The IVDMD of barley was generally higher than the other species at the soft and hard dough stages. The NDF, ADF, and lignin fractions usually increased from the vegetative to milk stages and remained unchanged or increased slightly through the hard dough stage. The ADF and lignin are negatively associated with forage digestibility while NDF values are negatively related to dry matter intake. The ADF of rye was generally higher than the other species at the milk and soft dough stages. Rye and barley contained more lignin than the other species from the heading through hard dough stage. Crude protein content generally decreased from the vegetative through milk stages and then leveled off or decreased slightly through the hard dough stage. Crude protein of oats was lower than other species at the vegetative stage, while rye generally contained more crude protein than the other species at the vegetative and boot stages. These data in combination with forage yield data reported in an associated paper suggest that small grains can offer a nutritious source of animal feed for farmers in the southeastern United States. Rye tended to stand out among the species at the early stages of growth (vegetative to boot) as a highly digestible green chop or grazing crop that is also high in protein. Barley and wheat stand out as excellent high yielding, nutritious silage choices at the soft dough stage. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809369993 VL - 29 IS - 7-8 SP - 881-899 SN - 1532-2416 ER - TY - JOUR TI - Using the DRAINMOD-N model to study effects of drainage system design and management on crop productivity, profitability and NO3-N losses in drainage water AU - Breve, MA AU - Skaggs, RW AU - Parsons, JE AU - Gilliam, JW T2 - AGRICULTURAL WATER MANAGEMENT AB - The environmental impacts of agricultural drainage have become a critical issue. There is a need to design and manage drainage and related water table control systems to satisfy both crop production and water quality objectives. The model DRAINMOD-N was used to study long-term effects of drainage system design and management on crop production, profitability, and nitrogen losses in two poorly drained soils typical of eastern North Carolina (NC), USA. Simulations were conducted for a 20-yr period (1971–1990) of continuous corn production at Plymouth, NC. The design scenarios evaluated consisted of three drain depths (0.75, 1.0, and 1.25 m), ten drain spacings (10, 15, 20, 25, 30, 40, 50, 60, 80, and 100 m), and two surface conditions (0.5 and 2.5 cm depressional storage). The management treatments included conventional drainage, controlled drainage during the summer season and controlled drainage during both the summer and winter seasons. Maximum profits for both soils were predicted for a 1.25 m drain depth and poor surface drainage (2.5 cm depressional storage). The optimum spacings were 40 and 20 m for the Portsmouth and Tomotley soils, respectively. These systems however would not be optimum from the water quality perspective. If the water quality objective is of equal importance to the productivity objective, the drainage systems need to be designed and managed to reduce NO3–N losses while still providing an acceptable profit from the crop. Simulated results showed NO3–N losses can be substantially reduced by decreasing drain depth, improving surface drainage, and using controlled drainage. Within this context, NO3–N losses can be reduced by providing only the minimum subsurface drainage intensity required for production, by designing drainage systems to fit soil properties, and by using controlled drainage during periods when maximum drainage is not needed for production. The simulation results have demonstrated the applicability of DRAINMOD-N for quantifying effects of drainage design and management combinations on profits from agricultural crops and on losses of NO3–N to the environment for specific crop, soil and climatic conditions. Thus, the model can be used to guide design and management decisions for satisfying both productivity and environmental objectives and assessing the costs and benefits of alternative choices to each set of objectives. DA - 1998/1// PY - 1998/1// DO - 10.1016/S0378-3774(97)00035-8 VL - 35 IS - 3 SP - 227-243 SN - 1873-2283 KW - DRAINMOD-N model KW - drainage KW - controlled drainage KW - nitrogen losses KW - water quality KW - productivity KW - profitability ER - TY - JOUR TI - The impact of pesticide use on groundwater in North Carolina AU - Wade, HF AU - York, AC AU - Morey, AE AU - Padmore, JM AU - Rudo, KM T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Abstract A North Carolina study revealed that certain pesticides have impacted groundwater above health‐based standards in vulnerable areas. Ninety‐seven shallow, surficial aquifer‐monitoring wells were sampled at least twice. Sites for the monitoring wells were chosen based on an evaluation with the Pesticide DRASTIC model and a known record of pesticide use. Where possible, areas of greater risk were intentionally selected. Twenty‐three pesticides or pesticide degradates were detected in 26 of the 97 wells. Nine of the pesticides or degradates are no longer registered for use; two of these chemicals, dibromochloropropane and methylene chloride, were found in excess of health‐based guidance levels (HBGL) or state groundwater quality standards (GWQS). Of the registered pesticides or their degradates, the herbicides dichlorprop and simazine and the insecticide isomers BHC‐alpha and BHC‐delta were in excess of HBGL. The herbicide atrazine was detected at 83% of its GWQS. The U.S. Environmental Protection Agency (USEPA) Pesticides and Groundwater State Management Plans will be required for atrazine and simazine to be sold and used, which will provide additional protection to public health and the environment. Pesticide DRASTIC ratings or soil‐leaching potential values and the proportion of wells were unrelated to pesticide detections. DA - 1998/// PY - 1998/// DO - 10.2134/jeq1998.00472425002700050006x VL - 27 IS - 5 SP - 1018-1026 SN - 0047-2425 ER - TY - CONF TI - Stream water level control to enhance riparian buffer effectiveness removing nitrate-nitrogen AU - Parsons, J. E. AU - Gilliam, J. W. AU - Mikkelsen, R. L. C2 - 1998/// C3 - Drainage in the 21st century: Food production and the environment: Proceedings of the seventh International Drainage Symposium CN - TC970 .I56 1998 DA - 1998/// SP - 551-558 PB - St. Joseph, Michigan: American Society of Agricultural Engineers ER - TY - JOUR TI - Software for mapping and analyzing weed distributions: gWeedMap AU - Krueger, DW AU - Coble, HD AU - Wilkerson, GG T2 - AGRONOMY JOURNAL AB - Abstract The spatial pattern of weeds in a field is often patchy. This pattern can be visualized with maps created by geographical information system (GIS) software. However, this software is often difficult to use and/or expensive, especially if not all of the GIS functionality is needed. The objective of this project was to develop a means of easily and economically generating weed maps. This was accomplished by creating a PC‐based Windows software tool to generate weed maps from scouting information. The scout enters weed data that has been collected in a gridded, systematic sampling protocol. From this information, the program creates a map for each weed species in the field. Scouting data can be density, percent cover, or any other type of measurement. Five data ranges are displayed on the map, with the user specifying the data values and map colors associated with each range. Various statistics are calculated, such as the average density of each species. Weed diversity in each field is determined with Shannon's diversity index and evenness index. These indices are also calculated with the density data weighted by the competitiveness of each weed species. This gives the weed ecologist a quantitative measure of the competitive diversity, which is related to the impact of the weed population on yield loss. DA - 1998/// PY - 1998/// DO - 10.2134/agronj1998.00021962009000040018x VL - 90 IS - 4 SP - 552-556 SN - 1435-0645 ER - TY - JOUR TI - Site-specific regulatory interaction between spinach leaf sucrose-phosphate synthase and 14-3-3 proteins AU - Toroser, D AU - Athwal, GS AU - Huber, SC T2 - FEBS LETTERS AB - We report an Mg2+-dependent interaction between spinach leaf sucrose-phosphate synthase (SPS) and endogenous 14-3-3 proteins, as evidenced by co-elution during gel filtration and co-immunoprecipitation. The content of 14-3-3s associated with an SPS immunoprecipitate was inversely related to activity, and was specifically reduced when tissue was pretreated with 5-aminoimidazole-4-carboxamide riboside, suggesting metabolite control in vivo. A synthetic phosphopeptide based on Ser-229 was shown by surface plasmon resonance to bind a recombinant plant 14-3-3, and addition of the phosphorylated SPS-229 peptide was found to stimulate the SPS activity of an SPS:14-3-3 complex. Taken together, the results suggest a regulatory interaction of 14-3-3 proteins with Ser-229 of SPS. DA - 1998/9/11/ PY - 1998/9/11/ DO - 10.1016/S0014-5793(98)01048-5 VL - 435 IS - 1 SP - 110-114 SN - 0014-5793 KW - sucrose-phosphate synthase KW - 14-3-3 protein KW - Spinach KW - protein : protein interaction KW - surface plasmon resonance ER - TY - JOUR TI - Selection for resistance and tolerance to oat mosaic virus and oat golden stripe virus in hexaploid oats AU - Walker, SL AU - Leath, S AU - Murphy, JP AU - Lommel, SA T2 - PLANT DISEASE AB - Coker 716, a hexaploid oat cultivar resistant to both oat mosaic virus (OMV) and oat golden stripe virus (OGSV) was crossed to three susceptible cultivars (Brooks, Madison, and Tech) to form three individual populations. Individual breeding lines were derived from each cross in the F2 generation and tested in plots consisting of equally spaced individual hills in OMV- and OGSV-infested soils and non-infested soils to evaluate resistance and yield loss of individual lines. Foliar symptoms, harvest index, and yield loss were examined as selection criteria for resistant genotypes. The study was conducted over 2 years at two North Carolina locations that differed in soil type and climate. Multiple regression models describing yield loss in each cross due to rating, year, and location were calculated. Coefficients of multiple determination in these models ranged from 0.39 to 0.51. Yield loss ranged from 39 to 60% among different crosses. Infection by OMV and OGSV accounted for the majority of yield loss in two of the populations. Disease severity varied widely over years and locations. The results suggest that selection of lines with symptomatic tissue of 10% or less, or selection of tolerant lines, is needed for breeding progress. DA - 1998/4// PY - 1998/4// DO - 10.1094/PDIS.1998.82.4.423 VL - 82 IS - 4 SP - 423-427 SN - 0191-2917 KW - multiple regression model KW - soil-borne virus ER - TY - JOUR TI - Relationship of soil properties to parent material and landscape position in eastern Madre de Dios, Peru AU - Osher, LJ AU - Buol, SW T2 - GEODERMA AB - Properties of soils in the eastern part of Madre de Dios, Peru, were characterized and related to landscape position and parent material texture. Level uplands, dissected side slopes and recent flood plains dominate the topography in this region. Soil textures vary from clayey to sandy, depending on the texture of sedimentary materials from which each pedon formed. Parent material textural variation is a result of differences in the energy of the meandering rivers that deposited the ancient alluvium. Fourteen soil profiles were described and sampled in the field and analyzed in the laboratory. Data for eight soil profiles representative of the region are presented here. The profiles include soils formed in both sandy and fine-textured parent materials and soils with moisture status ranging from well drained to poorly drained. Soil moisture conditions vary with position on the landscape, such that as distance from streams increases, average depth to the fluctuating water table decreases. Redoximorphic features are present in all mineral soils. The average depth to redoximorphic features is least in locations furthest from streams. Soils in landscape positions that are poorly or somewhat poorly drained contain significant amounts of plinthite. In all soils, kaolinite is the dominant mineral in the <0.2 μm fraction, while quartz is the dominant mineral in very fine and fine sand fractions. All soils have low cation exchange capacity (CEC), low base saturation, and acid pH. Coarse-textured spodic soils with well developed zones of iron and organic matter translocation are formed in recent sand deposits of flood plains of 2nd-order streams. Organic soils are found in the wetlands associated with flood plains of some 3rd-order streams. Most properties of these soils appear to be controlled by the textures of their sedimentary parent materials and by their position on the landscape. The soils classify as Paleustults, Plinthaquults, Kandiustults, Placaquods and Troposaprists according to Soil Taxonomy. New subgroups of Paleustult are proposed. DA - 1998/4// PY - 1998/4// DO - 10.1016/S0016-7061(97)00133-X VL - 83 IS - 1-2 SP - 143-166 SN - 0016-7061 KW - plinthite KW - kandic horizon KW - Kandiustult KW - Plinthaquult KW - Paleustult KW - Placaquod ER - TY - JOUR TI - Properties of ultisols and oxisols related to Mehlich-3 phosphorus buffer coefficients AU - Aquino, BF AU - Sobral, LF AU - Cox, FR T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract The accuracy of phosphorus (P) fertilizer recommendations can be improved by knowing the soil buffering capacity. Field estimates of the change in Mehlich‐3 P per unit of P applied after one year, termed the Field Mehlich‐3 P Buffer Coefficient (M3PBC), were available from five Ultisols and five Oxisols. Specific surface area (SSA), clay content, and iron (Fe) and aluminum (Al) extractable by both citrate‐bicarbonate‐dithionite (CBD) and oxalate (Oxa) were determined on these soils and the results related to the Field M3PBC. The Field M3PBC was highly correlated linearly with SSA and clay content. Also, Field M3PBC was related well with CBDFe, CBDAl, and their summation. Neither OxaFe, OxaAl, nor their summation was correlated with Field M3PBC. The relationship between Field M3PBC and these factors was exponential. Specific surface area and clay gave the best relationships, but Field M3PBC could also be predicted from the CBD summation of Fe and Al, CBDFe alone, or CBDAl alone, in that order. Knowledge of CBD‐extractable Fe and/or Al can be used to establish the rate of fertilizer required to increase the Mehlich‐3 P to a sufficient level on Ultisols and Oxisols. An estimate of CBDFe is available from soil survey data and it should be applicable within a region. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809370016 VL - 29 IS - 9-10 SP - 1155-1166 SN - 0010-3624 ER - TY - JOUR TI - Nitrogen and defoliation management: Effects on yield and nutritive value of flaccidgrass AU - Burns, J. C. AU - Chamblee, D. S. AU - Belesky, D. P. AU - Fisher, D. S. AU - Timothy, D. H. T2 - Agronomy Journal AB - Abstract ‘Carostan’ flaccidgrass ( Pennisetum flaccidum Griseb.), a C 4 perennial grass, has shown high quality potential in animal trials. Its yield response to defoliation frequency and N fertilization, however, has not been reported. We examined the influence of stubble height and of a range of N applications in two defoliation experiments over 4 yr. Experiment 1 (Raleigh, NC) combined two harvest heights, 76 and 38 cm, with two stubble heights, 25 and 15 cm (76–25, 76–15, 38–25, 38–15); all treatments received 380 kg N ha −1 yr −1 . After Year 1, the 76–15 defoliation produced higher yields than 76–25 (Year 2: 11 330 vs. 7930 kg ha −1 , P < 0.001; Year 3:8950 vs. 6270 g kg −1 , P < 0.001), while in vitro dry matter disappearance (IVDMD) was similar (Year 3) (mean = 582 g kg −1 ). Compared with 38–15, the 38–8 defoliation resulted in lower yields (Year 2: 8638 vs. 9344 kg ha −1 , P = 0.001; Year 3, 6173 vs. 8090 kg ha −1 , P = 0.07) but higher IVDMD (Year 3, 651 vs. 635 g kg −1 , P < 0.01). Experiment 2 (Raleigh, NC, and Watkinsville, GA) had four defoliations: clipping to 5 cm at 20 and 51 cm (vegetative) and to 8 cm at boot and anthesis stages (20–5, 51–5, Boot—8, Anthesis—8). All defoliation treatments were topdressed with 291 kg N ha −1 , and 51–5 and Boot—8 were also evaluated with 179 and 403 kg N ha −1 (eight N—defoliation treatments in all). At both locations, highest yields were obtained with Anthesis—8, averaging 19 010 kg ha −1 at Raleigh and 12 390 kg ha −1 at Watkinsville. The 20–5 defoliation resulted in lowest yields at both locations, averaging 7648 kg ha −1 at Raleigh and 5100 kg ha −1 at Watkinsville. Defoliation frequency altered IVDMD (range = 550 to 789 g kg −1 ), but N application did not; however, increasing N application increased N concentrations linearly ( P = 0.05). Flaccidgrass had high yield potential and high nutritive value at the Raleigh location, and warrants further evaluation in the upper South. DA - 1998/// PY - 1998/// DO - 10.2134/agronj1998.00021962009000010016x VL - 90 IS - 1 SP - 85-92 ER - TY - JOUR TI - Nitrogen and carbon cycling in relation to cover crop residue quality AU - Wagger, M. G. AU - Cabrera, M. L. AU - Ranells, N. N. T2 - Journal of Soil & Water Conservation DA - 1998/// PY - 1998/// VL - 53 IS - 3 SP - 214-218 ER - TY - PAT TI - Modified urf13-T protein C2 - 1998/// DA - 1998/// PY - 1998/// ER - TY - JOUR TI - Interaction of bromoxynil and postemergence graminicides on large crabgrass (Digitaria sanguinalis) AU - Culpepper, AS AU - York, AC AU - Jennings, KM AU - Batts, RB T2 - WEED TECHNOLOGY AB - The effect of bromoxynil on large crabgrass control by clethodim, sethoxydim, fluazifop-P, fluazifop-P plus fenoxaprop-P, and quizalofop-P was evaluated in 1996 and 1997 in bromoxynil-tolerant cotton and in fallow areas. Bromoxynil at 560 g ai/ha reduced large crabgrass control 4 weeks after treatment (WAT) when mixed with labeled rates of fluazifop-P, fluazifop-P plus fenoxaprop-P, or quizalofop-P. Control 9 WAT was reduced when bromoxynil was mixed with any of the graminicides. Antagonism with the mixtures was greatest with quizalofop-P, intermediate with fluazifop-P plus fenoxaprop-P and fluazifop-P, and least with clethodim and sethoxydim. Increasing the graminicide rate 50% in mixtures with bromoxynil alleviated antagonism only for clethodim. No antagonism was noted 9 WAT when bromoxynil was applied 3 d before or 3 d after application of clethodim or sethoxydim or when bromoxynil was applied 3 d after fluazifop-P plus fenoxaprop-P. Antagonism was observed when bromoxynil was applied 3 d before fluazifop-P plus fenoxaprop-P or when applied 3 d before or 3 d after fluazifop-P and quizalofop-P. Regardless of bromoxynil application, greatest yields were obtained from cotton treated with clethodim or sethoxydim. Bromoxynil applied 3 d before or 3 d after clethodim, sethoxydim, or fluazifop-P plus fenoxaprop-P did not reduce yield. Yield was reduced when bromoxynil was applied 3 d before or 3 d after application of fluazifop-P or quizalofop-P and when bromoxynil was mixed with any graminicide. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00044304 VL - 12 IS - 3 SP - 554-559 SN - 1550-2740 KW - Bromoxynil, 3,5-dibromo-4-hydroxybenzonitrile KW - clethodim, (E,E)-(+/-)-2-[1-[[(3-chloro-2-propenyl)oxy]imino]propyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one KW - fenoxaprop-P, (R)-2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid KW - fluazifop-P, (R)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid KW - quizalofop-P, (R)-2-[4-[(6-chloro-2-quinoxalinyl)oxy]phenoxy]propanoic acid KW - sethoxydim, 2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one KW - large crabgrass, Digitaria sanguinalis (L.) Scop. # DIGSA KW - cotton, Gossypium hirsutum L, 'Stoneville BXN 47' KW - antagonism KW - herbicide-tolerant crops KW - DIGSA ER - TY - JOUR TI - Hydration and removal of supported phospholipid films in aqueous surfactant solutions AU - Colberg, MT AU - Carnes, K AU - Saez, AE AU - Grant, CS AU - Hutchinson, K AU - Hesterberg, D T2 - THIN SOLID FILMS AB - Dynamic studies of the hydration and removal of phospholipid films attached to solid substrates were performed. The phospholipids used were 1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine (DPPE), and a modification of DPPE containing a fluorescent molecular probe: n-(5-fluoresceinthicarbamoyl)-1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine, triethylammonium salt (FITC-DPPE). The phospholipid films were exposed to water and aqueous solutions of the anionic surfactant sodium dodecyl sulfate (SDS). The film mass was determined as a function of time by means of a quartz crystal microbalance (QCM). The crystalline structure of the film during the hydration process was analyzed by means of wide-angle X-ray diffraction. At low surfactant concentrations (below 20% of the critical micelle concentration (CMC)), the presence of surfactant increased the hydration rate of the film, as well as its maximum water uptake. At surfactant concentrations as low as 50% of the CMC, competitive hydration and removal of the phospholipid film were observed. X-Ray diffraction measurements show that the crystal structure of the DPPE films did not change significantly upon exposure to water and surfactant solutions. In contrast, FITC-DPPE films exhibited changes in the long-range spacing of their crystalline structure upon hydration. DA - 1998/8/31/ PY - 1998/8/31/ DO - 10.1016/s0040-6090(98)00638-5 VL - 327 IS - 1998 Aug. 31 SP - 247-251 SN - 0040-6090 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032141167&partnerID=MN8TOARS KW - phospholipid KW - quartz crystal microbalance KW - hydration KW - surfactant ER - TY - JOUR TI - Heritability and resource allocation of aluminum tolerance derived from soybean PI 416937 AU - Bianchi-Hall, CM AU - Carter, TE AU - Rufty, TW AU - Arellano, C AU - Boerma, HR AU - Ashley, DA AU - Burton, JW T2 - CROP SCIENCE AB - AIuminum toxicity restricts soybean [Glycine max (L.) Merr.] yield included many growing areas. When correction of toxicity by management is impractical, an economically sound alternative is to develop AI tolerant cultivars. Heritability (h2) estimates for AI tolerance in hydroponics would aid in the efficient design of selection programs for cultivar development. Our objectives were to determine the h2 of AI tolerance in a F4-derived population using tap root extension in hydroponics culture as the indicator of tolerance. The 120 random F4-derived lines of sensitive ‘Young’ × tolerant PI 416937 were evaluated in the absence (NOAL) and presence (HIAL) of AI (2 μM AI3+ activity) by means of a split-plot design. AIuminum stress increased seedling tap root extension 3% in PI 416937 and decreased extension in Young 53%. Mean progeny performance decreased 31%. Analysis of variance revealed significant (P < 0.05) progeny and progeny × AI interaction effects, indicating heritable genetic variation for AI tolerance. The h2 under HIAL was moderate (0.57) on a single-replication basis and high (0.87) based upon five replicates, indicating the relative ease by which AI tolerance may be improved. Tolerance expressed as percent of control (PC) had a similar h2. Approximately 6% of the F4-derived progeny in this study were numerically similar to the parents for AI response under HIAL, suggesting that three to five genes may control AI tolerance and that a population size of 150 random inbred lines may be needed to assure full recovery of AI tolerance in the progeny of future breeding populations. Expected gain and risk avoidance analysis suggested that two or three replications are sufficient for initial screening of single seed descent (SSD) populations derived from the PI 416937 and that employment of this PI as a control enhances the ability of the breeder to discard inferior types during screening. Practical advice is presented to assist plant breeders in the efficient improvement of AI tolerance in soybean. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020040x VL - 38 IS - 2 SP - 513-522 SN - 1435-0653 ER - TY - JOUR TI - Biogeochemical cycles and processes leading to changes in mobility of chemicals in soils AU - Hesterberg, D T2 - AGRICULTURE ECOSYSTEMS & ENVIRONMENT AB - There is a general lack of long-term field research showing the environmental fate of soil contaminants after agricultural land is converted to other uses. One concern is that long-term changes in soil properties induced by an alternative land use might cause a non-linear increase in the solubility and mobility of soil chemical contaminants. If a fairly rapid increase in contaminant mobility is delayed for years, then this event may be difficult to predict and to control. To help provide insights to long-term fate of soil contaminants, this paper gives an overview of some factors controlling their solubility and mobility. Because of their indefinite residence time in soils, heavy metals and other trace elements input to agricultural lands with soil amendments may pose the greatest (albeit undetermined) long-term threat. Certain macronutrients, especially N and P, and organic pesticides may have shorter-term detrimental effects on water quality and the environment. Important properties influencing soil contaminant solubility and mobility are the type of contaminant (e.g., heavy metal cation, oxyanion, pesticide), soil matrix composition (e.g., mineralogy and organic matter content), soil heterogeneity, pH, redox potential, and variations in dissolved organic matter concentration. By understanding the mechanisms of contaminant binding in the soil in relation to these properties, the long-term fate of contaminants is more predictable. DA - 1998/2// PY - 1998/2// DO - 10.1016/S0167-8809(97)00110-2 VL - 67 IS - 2-3 SP - 121-133 SN - 1873-2305 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031955778&partnerID=MN8TOARS KW - contaminant KW - heavy metals KW - sorption KW - solubility KW - environment KW - agriculture ER - TY - JOUR TI - Barnyardgrass (Echinochloa crus-galli) control with postemergence applications of propanil and clomazone in dry- seeded rice (Oryza sativa) AU - Jordan, D. L. AU - Kendig, J. A. T2 - Weed Technology AB - Field experiments were conducted to compare barnyardgrass control and rice grain yield following a single postemergence (POST) application of propanil plus clomazone with single or repeat POST applications of propanil alone or single POST applications of propanil plus pendimethalin, molinate, quinclorac, or thiobencarb. In four of 10 experiments, propanil plus clomazone controlled barnyardgrass better than single or repeat applications of propanil alone or single applications of propanil plus pendimethalin, molinate, quinclorac, or thiobencarb. The most consistent increase in rice yield over a single application of propanil occurred where clomazone was applied in mixture with propanil. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00044274 VL - 12 IS - 3 SP - 537-541 ER - TY - JOUR TI - Utility of SSRs for determining genetic similarities and relationships in maize using an agarose gel system AU - Senior, ML AU - Murphy, JP AU - Goodman, MM AU - Stuber, CW T2 - CROP SCIENCE AB - Among maize ( Zea maize L.) breeders, there is a heightened awareness of the necessity for both maintaining genetic diversity for crop improvement and improving the quality of genetic resource management. Restriction fragment length polymorphisms (RFLPs) and isozymes can serve as genetic markers for estimating divergence or diversity; however, the limited number of polymorphic isozyme loci available and the labor intensive and time consuming nature of RFLPs make their use for this purpose prohibitive. Simple sequence repeats (SSRs), when resolved using agarose gels, may be a viable and costeffective alternative to RFLPs and isozymes. Ninety‐four elite maize inbred lines, representative of the genetic diversity among lines derived from the Corn Belt Dent and Southern Dent maize races, were assayed for polymorphism at 70 SSR marker loci using agarose gels. The 365 alleles identified served as raw data for estimating genetic similarities among these lines. The patterns of genetic divergence revealed by the SSR polymorphisms were consistent with known pedigrees. A cluster analysis placed the inbred lines in nine clusters that correspond to major heterotic groups or market classes for North American maize. A unique fingerprint for each inbred line could be obtained from as few as five SSR loci. The utility of polymerase chain reaction (PCR)‐based markers such as SSRs for measuring genetic diversity, for assigning lines to heterotic groups and for genetic fingerprinting equals or exceeds that of RFLP markers, a property that may prove a valuable asset for a maize breeding program. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800040034x VL - 38 IS - 4 SP - 1088-1098 SN - 0011-183X ER - TY - JOUR TI - Temperature effects on tocopherol composition in soybeans with genetically improved oil quality AU - Almonor, GO AU - Fenner, GP AU - Wilson, RF T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Tocopherol, a natural antioxidant, typically accounts for a small percentage of soybean ( Glycine max L. Merr.) oil. Alleles that govern the expression of polyunsaturated fatty acids in soybean germplasm are influenced by temperature. However, little is known about the environmental influences on tocopherol expression. The objective of this study was to assess the influence of temperature on tocopherol composition in soybean germplasm that exhibit homozygous recessive and dominant alleles that govern the predominant ω‐6 and ω‐3 desaturases. The control cv. Dare and three low‐18:3 genotypes (N78‐2245, PI‐123440, N85‐2176) were grown under controlled‐temperature environments during reproductive growth. Analysis of crude oil composition at various stages of seed development revealed a strong negative correlation between total tocopherol content and growth temperature. The relative strength of this correlation was greater in the germplasm that exhibited homozygous alleles governing the ω‐6 desaturase than those governing the ω‐3 desaturase. The decline in total tocopherol with reduced temperature was attributed predominantly to loss of γ‐tocopherol. However, γ‐tocopherol concentration also was directly related to 18:3 concentration in all genotypes. Thus, low‐18:3 oils contained both a lower content and a lower concentration of γ‐tocopherol. Although the biochemical basis for this observation is unknown, the antioxidant capacity of γ‐tocopherol appeared to be directly associated with changes in oil quality that were mediated more by genetic than by environmental influences on 18:3 concentration. Another aspect of this work showed that low‐18:3 soybean varieties should be expected to contain more α‐tocopherol, especially when grown under normal commercial production environments. This condition should be regarded as another beneficial aspect of plant breeding approaches to the improvement of soybean oil quality. DA - 1998/5// PY - 1998/5// DO - 10.1007/s11746-998-0070-3 VL - 75 IS - 5 SP - 591-596 SN - 0003-021X KW - environmental variation KW - genetics KW - Glycine max L. Merr. KW - linoleic acid KW - oil quality KW - alpha-tocopherol KW - gamma-tocopherol KW - tocopherol composition ER - TY - JOUR TI - Relation between diacylglycerol acyltransferase activity and oil concentration in soybean AU - Settlage, S. B. AU - Kwanyuen, P. AU - Wilson, R. F. T2 - Journal of the American Oil Chemists Society AB - Abstract Diacylglycerol acyltransferase (EC 2.3.1.20; DGAT) catalyzes synthesis of triacylglycerol from acyl‐CoA and diacylglycerol. Activity of this enzyme and developmental changes in oil accumulation were estimated at various stages of seed growth in soybean germplasm with phenotypic differences in oil content. Oil deposition in seed of these genotypes followed a sigmoid pattern that was modeled to predict incremental rates of oil accumulation during seed development. A strong positive correlation was found between the estimated peak rate of oil deposition (near the mid‐term of seed development) and oil concentration in mature seed. At saturating substrate levels, DGAT activity measured near the peak rate of oil deposition also was correlated positively with oil phenotype. In the latter stages of seed development, a positive correlation between estimates of enzyme activity at or below the apparent K m for diolein and comparable oil accumulation rates was attributed to reduced synthesis of substrates and/or potential change in affinity for substrate as suggested by an increase in apparent K m for diolein in older seed. These data indicated that DGAT activity may be a rate‐limiting step in triacylglycerol synthesis. However, it is difficult to accept the idea of a single rate‐limiting step at the end of a complex metabolic pathway. Because oil is a quantitatively inherited trait, several genes determine genotypic differences in oil content among soybeans. Hence, DGAT activity may be an indicator of coordinated genetic expression of gene‐products in the entire glycerolipid synthetic pathway for a given genotype. In any case, results of this investigation demonstrated that genotypic differences in DGAT activity contributed to expression of genetic variation in oil content among soybean gemplasm. DA - 1998/// PY - 1998/// DO - 10.1007/s11746-998-0225-2 VL - 75 IS - 7 SP - 775-781 ER - TY - JOUR TI - Phosphorus-deficiency effects on response of symbiotic N-2 fixation and carbohydrate status in soybean to atmospheric CO2 enrichment AU - Sa, TN AU - Israel, DW T2 - JOURNAL OF PLANT NUTRITION AB - Abstract The impact of phosphorus (P) deficiency on response of symbiotic N2 fixation and carbohydrate accumulation in soybean (Glycine max [L.] Merr.) to atmospheric CO2 enrichment was examined. Plants inoculated with Bradyrhizobium japonicum MN 110 were grown in growth chambers with controlled atmospheres of 400 and 800 μL CO2 L‐1 and supplied either 1.0 mM‐P (P‐sufficient) or 0.05 mM‐P (P‐deficient) nitrogen (N)‐free nutrient solution. When plants were supplied with sufficient P, CO2 enrichment significantly increased whole plant dry mass (83%), nodule mass (67%), total nitrogenase activity (58%), and N (35%) and P (47%) accumulation at 35 days after transplanting (DAT). Under sufficient P supply, CO2 enrichment significantly increased starch concentrations in nodules compared to the normal atmospheric CO2 treatment. Under normal CO2 levels (400 μL L‐1) nonstructural carbohydrate concentration (starch plus soluble sugar) was significantly higher in leaves of P‐deficient plants than in leaves of P‐sufficient plants in which nonstructural carbohydrate concentration exhibited a strong diurnal pattern. Under deficient P supply whole plant dry mass, symbiotic N2‐fixation parameters, and N and P accumulation were not enhanced by atmospheric CO2 enrichment. Phosphorus deficiency decreased nonstructural carbohydrate accumulation in nodules at the end of a 10‐day period in which functional activity was developing by 86% relative to P‐sufficient controls. While P deficiency elicited significant increases in the nonstructural carbohydrate concentration in leaves, it caused significant decreases in the nonstructural carbohydrate concentration in nodules over the diurnal cycle from 30 to 31 DAT. Collectively, these results indicate that the lack of a symbiotic N2‐fixation response to atmospheric CO2 enrichment by P‐deficient plants may be related to the decreased carbohydrate status of nodules. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365555 VL - 21 IS - 10 SP - 2207-2218 SN - 0190-4167 ER - TY - JOUR TI - Novel developmentally regulated phosphoinositide binding proteins from soybean whose expression bypasses the requirement for an essential phosphatidylinositol transfer protein in yeast AU - Kearns, MA AU - Monks, DE AU - Fang, M AU - Rivas, MP AU - Courtney, PD AU - Chen, J AU - Prestwich, GD AU - Theibert, AB AU - Dewey, RE AU - Bankaitis, VA T2 - EMBO JOURNAL AB - Article15 July 1998free access Novel developmentally regulated phosphoinositide binding proteins from soybean whose expression bypasses the requirement for an essential phosphatidylinositol transfer protein in yeast M. A. Kearns M. A. Kearns Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author D. E. Monks D. E. Monks Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author M. Fang M. Fang Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author M. P. Rivas M. P. Rivas Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author P. D. Courtney P. D. Courtney Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author J. Chen J. Chen Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT, 84112-5820 USA Search for more papers by this author G. D. Prestwich G. D. Prestwich Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT, 84112-5820 USA Search for more papers by this author A. B. Theibert A. B. Theibert Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author R. E. Dewey R. E. Dewey Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author V. A. Bankaitis Corresponding Author V. A. Bankaitis Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author M. A. Kearns M. A. Kearns Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author D. E. Monks D. E. Monks Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author M. Fang M. Fang Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author M. P. Rivas M. P. Rivas Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author P. D. Courtney P. D. Courtney Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author J. Chen J. Chen Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT, 84112-5820 USA Search for more papers by this author G. D. Prestwich G. D. Prestwich Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT, 84112-5820 USA Search for more papers by this author A. B. Theibert A. B. Theibert Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author R. E. Dewey R. E. Dewey Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA Search for more papers by this author V. A. Bankaitis Corresponding Author V. A. Bankaitis Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA Search for more papers by this author Author Information M. A. Kearns1, D. E. Monks2, M. Fang1, M. P. Rivas1, P. D. Courtney2, J. Chen3, G. D. Prestwich3, A. B. Theibert4, R. E. Dewey2 and V. A. Bankaitis 1 1Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA 2Department of Crop Science, North Carolina State University, Raleigh, NC, 27695-7620 USA 3Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT, 84112-5820 USA 4Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0005 USA *Corresponding author. E-mail: [email protected] The EMBO Journal (1998)17:4004-4017https://doi.org/10.1093/emboj/17.14.4004 PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info Phosphatidylinositol transfer proteins (PITPs) have been shown to play important roles in regulating a number of signal transduction pathways that couple to vesicle trafficking reactions, phosphoinositide-driven receptor-mediated signaling cascades, and development. While yeast and metazoan PITPs have been analyzed in some detail, plant PITPs remain entirely uncharacterized. We report the identification and characterization of two soybean proteins, Ssh1p and Ssh2p, whose structural genes were recovered on the basis of their abilities to rescue the viability of PITP-deficient Saccharomyces cerevisiae strains. We demonstrate that, while both Ssh1p and Ssh2p share ∼25% primary sequence identity with yeast PITP, these proteins exhibit biochemical properties that diverge from those of the known PITPs. Ssh1p and Ssh2p represent high-affinity phosphoinositide binding proteins that are distinguished from each other both on the basis of their phospholipid binding specificities and by their substantially non-overlapping patterns of expression in the soybean plant. Finally, we show that Ssh1p is phosphorylated in response to various environmental stress conditions, including hyperosmotic stress. We suggest that Ssh1p may function as one component of a stress response pathway that serves to protect the adult plant from osmotic insult. Introduction Phosphatidylinositol/phosphatidylcholine transfer proteins (PITPs) transfer either phosphatidylinositol (PI) or phosphatidylcholine (PC) between membrane bilayers in vitro (Cleves et al., 1991a; Wirtz, 1991), and this class of proteins exhibits two hallmark features of interest. First, PITPs are unique in that while these polypeptides contain one phospholipid (PL) binding site per protein monomer, PITPs have the ability to accommodate binding of two dissimilar PLs (PI and PC) in a mutually exclusive binding reaction. Secondly, PITPs exhibit a high level of primary sequence conservation. These homologies among PITPs are presently bifurcated into two distinct branches. PITPs of mammalian and insect origin share at least 40% primary sequence identity (Dickeson et al., 1989; Vihtelic et al., 1993; Tanaka and Hosaka, 1994; Chang et al., 1997). Fungal PITPs are also highly similar to each other at the primary sequence level (Bankaitis et al., 1989, 1990; Salama et al., 1990; Lopez et al., 1994), but share no primary sequence similarity with metazoan PITPs (Bankaitis et al., 1989; Dickeson et al., 1989; Vihtelic et al., 1993). The Saccharomyces cerevisiae SEC14 gene product (Sec14p) represents the major PITP of yeast, and plays an essential role in protein exit from the yeast Golgi complex (Bankaitis et al., 1989, 1990). A dissection of how Sec14p translates its PI/PC-exchange activity to biological function has been driven by the characterization of mutations that relieve cells of the normally essential Sec14p requirement for Golgi function and cell viability (Cleves et al., 1989, 1991b; Alb et al., 1996; Fang et al., 1996). Characterization of these ‘bypass Sec14p’ mutations has generated the proposal that Sec14p maintains the integrity of a critical Golgi diacylglycerol (DAG) pool that is required for Golgi secretory function (McGee et al., 1994; Kearns et al., 1997). An important aspect of this function is the ability of the PC-bound form of Sec14p to repress the activity of the CDP-choline pathway for PC biosynthesis (a potent DAG consumer) in yeast Golgi membranes (McGee et al., 1994; Skinner et al., 1995). The PI-bound form of Sec14p may function independently in potentiating PI metabolism in an action which would resupply the Golgi DAG pool. This mode of action is inferred from the demonstration that accelerated PI-turnover represents one in vivo mechanism for effecting a ‘bypass Sec14p’ phenotype (Kagiwada et al., 1996; Kearns et al., 1997), that the PI-transfer activity of mammalian PITP is necessary for rescue of Sec14p defects (Alb et al., 1995), and that both Sec14p and mammalian PITPs stimulate PI-metabolism in phosphoinositide-dependent reactions that have been reconstituted in permeabilized mammalian cells (Hay and Martin, 1993; Thomas et al., 1993; Hay et al., 1995; Cunningham et al., 1996). Indeed, PITP function prevents the onset of specific neurodegenerative diseases in Drosophila and mammals, although the in vivo mechanisms of PITP action remain unclear (Hamilton et al., 1997; Milligan et al., 1997). While fungal and metazoan PITPs have been analyzed in some detail, plant PITPs remain uncharacterized. Herein, we report the identification and characterization of two novel soybean Sec14p homologs, designated Ssh1p and Ssh2p. These homologs share some 25% sequence identity with Sec14p, and expression of these proteins is developmentally regulated in the plant. The primary sequence homologies shared by these SSH proteins with Sec14p translate to some level of functional relatedness since high-level expression of either Ssh1p or Ssh2p is sufficient for rescue of the growth and Golgi secretory defects associated with haploid lethal sec14Δ mutations. While Ssh2p exhibits robust PI-transfer activity in vitro, Ssh1p exhibits no such activity. Moreover, neither Ssh1p nor Ssh2p are capable of effecting PC transfer in vitro. In fact, both Ssh1p and Ssh2p are high-affinity phosphoinositide binding proteins that exhibit distinct phospholipid binding specificities. As such, Ssh1p and Ssh2p represent new members of the Sec14p family of proteins that exhibit novel biochemical properties. Finally, we report that Ssh1p is rapidly phosphorylated in response to the exposure of cells to a variety of environmental stresses (e.g. hyperosmotic stress) and that the phosphorylated form of Ssh1p fails to associate with membranes. The distinct biochemical properties of Ssh1p and Ssh2p, when coupled with their differentially regulated patterns of expression in the plant, suggest that Ssh1p and Ssh2p play distinct physiological roles. Ssh1p, in particular, may play a role in regulating the response of soybean plants to environments of high osmolarity. Results Identification of two functional homologs of yeast Sec14p from a higher plant Functional rescue of yeast Sec14p defects represents a simple method for recovering genes encoding heterologous PITPs (Skinner et al., 1993; Tanaka and Hosaka, 1994). To isolate higher plant PITP genes, we constructed a developing soybean seed cDNA library that was engineered for high-level expression in yeast (see Materials and methods). Fifteen cDNA clones, representing two distinct cDNA species designated SSH1 and SSH2, were recovered by virtue of their ability to rescue the growth defects of a sec14-1ts strain at 37°C (Figure 1A). Importantly, plasmid shuffle experiments (see Lopez et al., 1994) demonstrated that SSH1 and SSH2 expression also remedied the unconditional lethality associated with sec14Δ alleles (Figure 1A). Thus, the SSH1 and SSH2 gene products were able to substitute for Sec14p when expressed in yeast. However, this functional substitution required high-level expression of Ssh1p or Ssh2p, as evidenced by our finding that the introduction of centromeric plasmids bearing PPGK::SSH1 or PPGK::SSH2 cassettes was insufficient to support rescue of either sec14Δ or sec14-1ts alleles (e.g. strains CTY1013 and CTY1015; see Table I). Moreover, Ssh2p expression consistently yielded a superior improvement in growth of Sec14p-deficient strains relative to Ssh1p expression (Figure 1A). Figure 1.(A) Expression of soybean SSH1 and SSH2 genes rescues the growth defects of Δsec14 yeast and sec14-1ts strains. Growth properties of a wild-type yeast strain (CTY182), its isogenic sec14-1ts derivative (CTY1-1A), and various sec14 derivative strains carrying either YEp(SSH1) or YEp(SSH2) plasmids are shown. The sec14ts strains (CTY937 and CTY938) all represent strain CTY1-1A carrying the indicated plasmid, while the Δsec14 strains (CTY897 and CTY898) were generated by plasmid shuffle exactly as described by Lopez et al. (1994). These yeast strains were streaked onto YPD plates and incubated for 36 h at the indicated temperatures. High-level expression of either SSH1 or SSH2 not only restored growth of sec14-1ts strains at the normally restrictive temperature at 37°C, but also restored viability at all temperatures to yeast strains carrying the haploid-lethal Δsec14 allele. Thus, when expressed at high levels, Ssh1p and Ssh2p are individually able to fulfill in yeast the essential cellular functions of Sec14p. (B) Efficiency of invertase secretion at 37°C for Δsec14 strains carrying the indicated YEp(SSH) plasmids. The secretion index relates extracellular secreted invertase to total cellular invertase as described (Salama et al., 1990). The secretion indices of wild-type and sec14-1ts strains represent measures of normal secretory proficiency and the magnitude of the sec14-1ts Golgi secretory block, respectively. The Δsec14 strains CTY897 and CTY898 (see Table I) were analyzed for secretory competence to determine the efficiency with which SSH1 and SSH2 expression rescued Δsec14-associated secretory defects, respectively. These data indicate that Ssh1p and Ssh2p expression in yeast significantly alleviated the Golgi secretory defect associated with complete loss of Sec14p function. (C) Ssh1p and Ssh2p share primary sequence homology with fungal PITPs. An alignment of the entire Sec14p, Ssh1p, and Ssh2p primary sequences is shown, and corresponding residue numbers are designated at the far right of each column. These soybean polypeptides each share ∼25% primary sequence identity (and 50% similarity) with Sec14p. Composite identities are indicated by the residues boxed in black, while the Sec14p residues within the white boxes represent amino acid residues conserved in four of the fungal Sec14ps (i.e. Saccharomyces cerevisiae, Kluyveromyces lactis, Yarrowia lipolytica and Schizosaccharomyces pombe) we have characterized to date. Download figure Download PowerPoint Table 1. Yeast strains CTY-1A MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts CTY809 MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts/YEp lac195 CTY182 MATa, ura3-52, Δhis3-200, lys2-801am CTY807 MATa, ura3-52, Δhis3-200, lys2-801am/YEp lac195 CTY303 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG CTY808 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG/YEp lac195 CTY897 MATa, ade2, ade3, ura3-52, Δhis3-200, leu2, sec14ΔP::hisG/YEp(SSH1, URA3) CTY898 MATa, ade2, ade3, ura3-52, Δhis3-200, leu2, sec14ΔP::hisG/YEp(SSH2, URA3) CTY899 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG/YEp(SSH1) CTY900 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG/YEp(SSH2) CTY920 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG/YEp(SSH1HIS6) CTY937 MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts/YEp(SSH1) CTY938 MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts/YEp(SSH2) CTY940 MATa, ura3-52, Δhis3-200, cki, sec14ΔP::hisG/YEp(SSH2myc) CTY1013 MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts/YCp(PPGK::SSH1) CTY1015 MATa, ura3-52, Δhis3-200, lys2-801am, sec14-1ts/YCp(PPGK::SSH2) SSH1 or SSH2 expression alleviated sec14 growth defects and elicited significant relief of the secretory block associated with Sec14p insufficiencies. As shown in Figure 1B, wild-type strains grown at 37°C exhibited a secretion index (90.9 ± 0.4%) that indicated efficient trafficking of invertase through the secretory pathway to the cell surface. In contrast, an isogenic sec14-1ts strain exhibited a secretion index of only 28.2 ± 2.4%. This value was diagnostic of the accumulation of a major intracellular pool of invertase that is blocked in transit from the yeast Golgi complex (Bankaitis et al., 1989; Franzusoff and Schekman, 1989; Cleves et al., 1991b). However, expression of SSH1 and SSH2 elevated the secretion index of a sec14 null strain grown at 37°C to 55.8 ± 6.2% and 80.2 ± 1.8%, respectively, i.e. values substantially greater than those determined for the sec14-1ts strain at the restrictive temperature (Figure 1B). Again, in accordance with the growth phenotypes described above, Ssh2p expression elicited a reproducibly more efficient rescue of Sec14p-related Golgi secretory defects than did Ssh1p expression. Ssh1p and Ssh2p share primary sequence homology with fungal Sec14ps The nucleotide sequences of the SSH1 and SSH2 cDNAs were determined and found to encode respective open reading frames of 975 and 771 bp, respectively. These sequences have been registered with the DDBJ/EMBL/GenBank database with the following accession numbers: AF024651 (SSH1) and AF024652 (SSH2). SSH1 and SSH2 are inferred to encode proteins of 324 and 256 amino acid residues, respectively, with corresponding molecular masses of 36.9 and 29 kDa. Immunodetection of Ssh1p and Ssh2p, both from producing yeast strains and from soybean sources, provided data in excellent agreement with these expectations (see below). As shown in Figure 1C, Ssh1p and Ssh2p share ∼25% primary sequence identity and 50% similarity with each other, and with Sec14p. The alignments in Figure 1C indicate that the shared primary sequence motifs correspond to motifs that are highly conserved in all characterized fungal Sec14ps, including those from the budding yeast Kluyveromyces lactis (Salama et al., 1990), the dimorphic yeast Yarrowia lipolytica (Lopez et al., 1994), and the fission yeast Schizosaccharomyces pombe (H.B.Skinner and V.A. Bankaitis, unpublished data). In particular, the signature motifs LLRFLRARKF, DGRPVY, YYPERMGKFY and INAP of fungal Sec14ps were all clearly recognizable in the inferred Ssh1p and Ssh2p primary sequences (Figure 1C). No cDNAs from germinating soybean seed that encode proteins exhibiting primary sequence relatedness with mammalian PITPs were obtained in this functional screen. Expression of SSH genes is developmentally regulated in soybean The high frequency of recovery for SSH2 cDNA clones, relative to SSH1 cDNA clones, in our functional screen suggested the possibility that SSH2 was more highly expressed in developing seeds than was SSH1. Northern blot analyses indicated that such was indeed the case. The steady-state abundance of SSH1 transcripts was greatest in leaf and root tissue, and was of only low abundance in developing seeds (Figure 2). In contrast, SSH2 transcripts were most abundant in developing seeds. Only low levels of SSH2 poly(A)+-RNA were detected in leaf tissue and we were unable to detect SSH2 expression in roots (Figure 2). Immunoblotting experiments with the corresponding tissue extracts were entirely consistent with the Ssh1p and Ssh2p expression pattern as deduced from the Northern blot analysis (not shown). Finally, Southern blot analyses, where soybean genomic DNA was individually probed with SSH1 or SSH2 cDNA, revealed a rather simple banding pattern. While the intron/exon organization and pseudogene repertoire for each SSH gene remains undetermined, the banding complexity obtained is consistent with each SSH gene being either unique, or belonging to a small multigene family (Figure 2). Figure 2.Expression of SSH1 and SSH2 is developmentally regulated in the soybean plant. Total genomic DNA from young soybean leaves was isolated as described (Murray and Thompson, 1980). Genomic DNA (10 μg) was restricted with the indicated restriction enzymes, resolved by electrophoresis on 1% agarose gels, and hybridized to radiolabeled SSH1 and SSH2 probes. The restriction enzymes employed do not cleave the corresponding SSH cDNAs. Molecular length markers are presented at the left in kilobase units. Northern (mRNA) blot assays were conducted using 10 μg of poly(A)+ RNA recovered from the specified tissues. The molecular lengths of the hybridizing transcripts were estimated using RNA size standards (not shown). Download figure Download PowerPoint Ssh1p and Ssh2p are not typical PITPs High-level expression of mammalian PITP in yeast is sufficient to rescue the growth and secretory defects associated with sec14-1ts defects (Skinner et al., 1993). The rescue of sec14 defects associated with expression of Ssh1p or Ssh2p in yeast, when coupled with the primary sequence relatedness of Ssh1p and Ssh2p to Sec14p (Figure 1C), suggested that Ssh1p and Ssh2p represented soybean PITPs. As a qualitative test of this possibility, we individually expressed Ssh1p and Ssh2p in the cki, sec14Δ yeast strain CTY303 (Table I) and measured the ability of cytosol prepared from these strains to effect PI and PC transfer in vitro. CTY303 was employed for these studies because it is devoid of endogenous PI- or PC-transfer activity as a consequence of the sec14Δ lesion. This strain retains full viability, in spite of the haploid-lethal nature of sec14Δ, because of the ‘bypass Sec14p’ property of the cki lesion which inactivates choline kinase, the first enzyme of the CDP–choline pathway for PC biosynthesis (Cleves et al., 1991b; Skinner et al., 1993). In these experiments, cytosol represented a clarified salt-stripped fraction of broken cell lysate (see Materials and methods). Salt-stripping was performed because significant fractions of both Ssh1p and Ssh2p were membrane associated (see below). Analysis of the phospholipid transfer properties of Ssh1p and Ssh2p cytosol, prepared from CTY303, yielded unanticipated results, and data are shown in Figure 3A and B. As positive control, the phospholipid transfer activities of wild-type yeast (Sec14p) cytosol were individually measured, and robust PI- and PC- transfer activities were recorded. Both transfer activities were linear in the range of 0 to at least 2 mg added cytosol, and 2 mg wild-type yeast cytosol effected ∼8 and 16% of total input radiolabeled PI- and PC-substrate, respectively, under the employed experimental conditions. Ssh2p cytosol also exhibited robust PI-transfer activity. Indeed, the PI-transfer activity of Ssh2p cytosol was in excess of that measured for Sec14p cytosol, which resulted from Ssh2p expression being driven by a powerful promoter from an expression cassette carried by a multicopy plasmid. Immunoblotting data were consistent with Ssh2p levels in cytosol preparations markedly exceeding those recorded for Sec14p in wild-type yeast cytosol (not shown). Yet, PC-transfer activity was essentially undetectable in Ssh2p cytosol (Figure 3A and B). The demonstration that Ssh2p cytosol effected efficient PI-transfer indicated that our inability to measure PC-transfer was neither the trivial result of inefficient recovery of Ssh2p, nor the result of catastrophic degradation of Ssh2p during cytosol preparation. Characterization of Ssh1p cytosol also provided unanticipated results as it failed to support significant PI- or PC-transfer activity, even at high concentrations (Figure 3A and B). The stability of Ssh1p during the cytosol preparation was not a contributory factor to our inability to record PI- and PC-transfer activity since high levels of full-length Ssh1p were detected by immunoblotting of input cytosol (not shown). Figure 3.Phospholipid transfer activities of cytosol prepared from Ssh1p- and Ssh2p-expressing strains of yeast. A wild-type yeast strain carrying a YEpURA3 plasmid (CTY807), and strains CTY808, Δsec14cki/YEp(URA3); CTY899, Δsec14cki/YEp(PADH::SSH1); and CTY900 Δsec14cki/YEp(PADH::SSH2) were grown in minimal media lacking uracil to mid-logarithmic phase and cells harvested by centrifugation. Cytosol was prepared by adjustment of cell-free extracts to a final concentration of 500 mM KCl and collection of the 100 000 g supernatant fraction (see Materials and methods). The protein concentrations of the resulting cytosolic fractions were determined and the samples were assayed for PI- and PC-transfer activity as described elsewhere (Aitken et al., 1990). PI- and PC-transfer data are shown separately in (A) and (B), respectively. Activity is expressed as the percent of total radiolabeled PI or PC in the assay that was transferred during the course of the experiment after subtraction of background. The background was represented by the transfer values acheived with the PI-/PC-transfer protein deficient cytosol prepared from strain CTY808. Values recorded for the wild-type yeast strain CTY807 (closed circles; designated WT) measure the Sec14p activity normally present in yeast cytosol and serve as positive controls. Values recorded for Ssh1p cytosol (CTY899) and Ssh2p cytosol (CTY900) are represented by stippled squares [YEp(SSH1)] and open circles [YEp(SSH2)], respectively. Data represent the averages of at least three independent experiments. (C) Phospholipid transfer properties of purified Ssh1p and Ssh2p. Recombinant His6-tagged Ssh1p, Ssh2p and Sec14p were purified from E.coli and assayed for PI- and PC-transfer activity as described in the Materials and methods. The efficiency of phospholipid transfer for each Sec14p assay was set at 100% transfer, and the transfer activities of Ssh1p and Ssh2p were compared accordingly. In these assays, recombinant proteins were added at amounts that sustained transfer activity in the linear range with respect to protein concentration, and these amounts are indicated at the bottom. Data represent the averages of at least three independent experiments. Note that >5 μg of Sec14p saturated the PI- and PC-transfer assays, whereas 10-fold greater amounts of recombinant Ssh2p were required to generate comparable PI-transfer activity. Even large amounts of purified recombinant Ssh1p (200 μg) failed to yield measurable PI- or PC-transfer activity. Assay of 200 μg of Ssh2p also failed to generate significant PC-transfer activity. For transfer assays, total input [3H]phosphatidylinositol and [14C]phosphatidycholine equalled ∼7000 and 27 000 c.p.m. per assay, respectively. Background for PI- and PC-transfer assays ranged between 100–198 and 643–800 c.p.m. per transfer reaction, respectively. Download figure Download PowerPoint The yeast cytosol data suggested that neither Ssh1p nor Ssh2p represented typical PITPs, i.e. proteins that exhibit both PI- and PC-transfer activity. To effect a more quantitative comparison of the phospholipid transfer activities of these Sec14p homologs, we expressed His6-tagged Ssh1p and Ssh2p in E.coli. The phospholipid transfer properties of the purified proteins were then determined. As illustrated in Figure 3C, the data obtained with Ssh1p and Ssh2p purified from E.coli broadly recapitulated the results generated with the corresponding yeast cytosol preparations. Ssh1p was inactive with respect to PI- or PC-transfer activity, even when 200 μg of purified protein were assayed. Yet, we believe that the relevant functional properties of Ssh1p are retained in the recombinant protein (see below). Recombinant Ssh2p scored as an active PI-transfer protein (Figure 3C), but was substantially weaker than Sec14p in activity. From titration experiments, we estimate His6-Sec14p purified from E.coli exhibited ∼10-fold greater specific activity for PI-transfer than did His6-Ssh2p recovered from the same source. As expected, in marked contrast to the robust PC-transfer activity elaborated by His6-Sec14p, purified His6-Ssh2p was inactive for PC transfer (Figure 3C), even at 200 μg Ssh2p per PC-transfer assay (not shown). The collective data indicate Ssh1p and Ssh2p exhibit biochemical properties that diverge from those associated with all other presently known PITPs that are characterized by their abilities to effect both PI and PC transfer. Ssh1p is devoid of both PI- and PC-transfer activity, whereas Ssh2p is a novel PI-transfer protein that elaborates PI-transfer activity in the absence of accompanying PC-transfer activity. Ssh1p and Ssh2p are novel phosphoinositide binding proteins We had previously demonstrated that the PI-transfer activity of mammalian PITP was required for expression of this protein to effect a heterologous rescue of Sec14p growth and secretory defects in yeast (Alb et al., 1995). Since mammalian PITP stimulates phosphatidylinositol-4,5-bisphosphate (PIP2) synthesis in permeabilized cells (Cunningham et al., 1995; Hay et al., 1995), we used a photoaffinity radiolabeling strategy to ascertain whether Ssh1p and Ssh2p represented phosphoinositide binding proteins. Specifically, we employed [3H]triester-BZDC-PI(4,5)P2 {[([3H](p-benzoyldihydrocinnamidyl)-amino) propyl]-phosphatidylinositol-4,5-bisphosphate} and [3H]triesterBZDC-InsP3 {[([3H](p-benzoyldihydrocinnamidyl)-amino) propyl]-inositol-1,4,5-trisphosphate} as photo- affinity ligands (Dorman and Prestwich, 1994; Prestwich, 1996; Prestwich et al., 1997, 1998). Both ligands had previously been shown to exhibit highly selective IP3 and PIP2-displaceable photocovalent modification of the pleckstrin homology domain of phospholipase Cδ1 (Tall et al., 1997), and [3H]triester-BZDC photoprobes were successfully employed to characterize the phosphoinositide binding specificity of the mammalian Golgi coatomer complex (Chaudhary et al., 1998). Neither His6-Ssh1p nor His6-Ssh2p were efficiently photolabeled by the PIP2 headgroup photoprobe [3H]BZDC-IP3, even though the control PIP2 binding protein, gelsolin, exhibited intense photolabeling that was competed by excess unlabeled PIP2 (not shown). However, both His6-Ssh1p and His6-Ssh2p were successfully labeled by the [3H]BZDC-PIP2 ligand, and binding of this phosphotriester photoprobe was competed by challenge with excess unlabeled PIP2 (Figure 4A). As expected, the known PIP2 binding protein gelsolin also exh DA - 1998/7/15/ PY - 1998/7/15/ DO - 10.1093/emboj/17.14.4004 VL - 17 IS - 14 SP - 4004-4017 SN - 0261-4189 KW - phosphatidylinositol transfer proteins KW - phosphoinositides KW - signaling KW - soybean KW - stress response ER - TY - JOUR TI - In vitro rooting and early greenhouse growth of micropropagated Paulownia elongata shoots AU - Bergmann, BA AU - Whetten, R T2 - NEW FORESTS DA - 1998/3// PY - 1998/3// DO - 10.1023/A:1006591704075 VL - 15 IS - 2 SP - 127-138 SN - 0169-4286 KW - auxin KW - princess tree KW - tissue culture ER - TY - JOUR TI - Evidence for reutilization of nodule iron in soybean seed development AU - Burton, JW AU - Harlow, C AU - Theil, EC T2 - JOURNAL OF PLANT NUTRITION AB - Abstract Iron (Fe) is required in plants for the function of the important processes of photosynthesis, respiration, DNA synthesis, and nitrogen (N) fixation. Concentrations of Fe show tissue specific changes during development. In soybean seeds, Fe accumulates through the linear phase of seed development, but the source of seed Fe, whether remobilized from other tissues or taken from the root environment, is not known. Root nodules of legumes have higher concentrations of Fe than other vegetative organs. To examine whether nodules could provide Fe to the seeds, two cultivars (Tokyo and Arksoy), differing in seed ferritin and Fe content were grown in a phytotron and given a single dose of 59Fe‐EDTA early in development [15 days after inoculation with Bradyrhizobium (DAI)]. The 59Fe distribution as well as immunoreactive ferritin were examined throughout development in nodule, leaf, and seed tissue. Leaves, nodules, and seeds accounted for 75 to 87% of the total plant 59Fe throughout the reproductive period with seeds increasing from 0 to 35–46% at maturity. The largest decrease in 59Fe occurred in nodules. If all 59Fe lost from nodules were translocated to seeds, then 40–59% of 59Fe in seeds could have come from nodules for Tokyo or Arksoy, respectively. The remaining seed Fe came from vegetative tissue and from the rhizosphere. Seed 59Fe in Tokyo was 2.5 times that of Arksoy. In both cultivars, 59Fe, soluble Fe, and ferritin concentrations in seed decreased from 39 DAI until maturity, suggesting that dry weight accumulation in seeds proceeds at a faster rate than Fe accumulation. Nodule ferritin remained constant suggesting a role in concentrating Fe for reutilization as nodules begin to senesce and decline in function. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365453 VL - 21 IS - 5 SP - 913-927 SN - 1532-4087 ER - TY - JOUR TI - Effects of genetic modification of nitrate reductase expression on (NO3-)-N-15 uptake and reduction in Nicotiana plants AU - Gojon, A AU - Dapoigny, L AU - Lejay, L AU - Tillard, P AU - Rufty, TW T2 - PLANT CELL AND ENVIRONMENT AB - The physiological consequences for NO3– utilization by the plant of underexpression and overexpression of nitrate reductase (NR) were investigated in nine transformants of Nicotiana tabacum and Nicotiana plumbaginifolia. The in vitro NR activities (NRAs) in both roots and leaves of low- and high-NR tobacco transformants ranged from 5–10% to 150–200%, respectively, of those measured in wild-type plants. The level of NR expression markedly affected the NO3– reduction efficiency in detached leaves and intact plants. In both species, 15NO3– reduction ranged from 15–45% of 15NO3– uptake in the low-NR plants, to 40–80% in the wild-type, and up to 95% in high-NR plants. In the high-NR genotypes, however, total 15NO3– assimilation was not significantly increased when compared with that in wild-type plants, because the higher 15NO3– reduction efficiency was offset by lower 15NO3– uptake by the roots. The inhibition of NO3– uptake appeared to be the result of negative feedback regulation of NO3– influx, and is interpreted as an adjustment of NO3– uptake to prevent excessive amino acid synthesis. In genotypes underexpressing NR, the low 15NO3– reduction efficiency also was generally associated with a decrease in net 15NO3– uptake as compared with the wild type. Thus, underexpression of NR resulted in an inhibition of reduced 15N synthesis in the plant, although the effect was much less pronounced than that expected from the very low NRAs. The restricted NO3– uptake in low-NR plants emphasizes the point that the products of NO3– assimilation are not the only factors responsible for down-regulation of the NO3– uptake system. DA - 1998/1// PY - 1998/1// DO - 10.1046/j.1365-3040.1998.00269.x VL - 21 IS - 1 SP - 43-53 SN - 0140-7791 KW - Nicotiana tabacum KW - Nicotiana plumbaginifolia KW - nitrate reductase KW - NO3- reduction KW - NO3- uptake KW - N efficiency KW - transgenic tobacco KW - whole-plant regulation ER - TY - JOUR TI - Effects of elevated [CO2] and/or ozone on limitations to CO2 assimilation in soybean (Glycine max) AU - Reid, CD AU - Fiscus, EL T2 - JOURNAL OF EXPERIMENTAL BOTANY DA - 1998/5// PY - 1998/5// DO - 10.1093/jexbot/49.322.885 VL - 49 IS - 322 SP - 885-895 SN - 1460-2431 KW - CO2 by O-3 interactions KW - elevated [CO2] KW - O-3 fumigation KW - Rubisco carboxylation efficiency KW - RuBP regeneration ER - TY - JOUR TI - Effects of controlled drainage on forest water quality AU - Amatya, DM AU - Gilliam, JW AU - Skaggs, RW AU - Lebo, ME AU - Campbell, RG T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Abstract The effects of controlled drainage (CD) on hydrology and water quality are presented for three eastern North Carolina watersheds in loblolly pine ( Pinus taeda L.). Timing of CD treatments were: the spring fish recruitment period in the downstream estuary in one watershed, and the summer‐fall period to facilitate tree growth in another watershed. A third watershed was maintained under conventional drainage throughout the study. It was demonstrated that seasonal controlled drainage can reduce both the total drainage outflows and corresponding sediment and nutrient exports. For example, CD reduced drainage outflows by as much as 88% during the summer‐fall and 39% during the spring with annual average reduction of 20 to 25%. Annual average total phosphorus (TP) and ammonium‐nitrogen (NH 4 ‐N) exports from watersheds under treatment were reduced by 7 to 72% as compared to the watershed under conventional drainage. For other nutrients and total suspended solids (TSS), concentrations were significantly different (α = 0.05) among the three watersheds during the winter when they were all under conventional drainage. This indicated characteristic differences unrelated to applied treatments. Taking these differences into account, the reductions in annual average export of TSS (up to 47%) and nitrate plus nitrite‐nitrogen (NO 3 +NO 2 ‐N) (up to 16%), total Kjeldahl nitrogen (TKN) (up to 45%) and total organic carbon (TOC) (up to 33%) from watersheds under treatment were directly attributed to reduction in outflows. Even though CD appeared to have increased concentrations of some of the nutrients analyzed, except for NH 4 ‐N, the applied treatments lowered the export of TSS and most nutrients measured. It is concluded that CD can be used to reduce TSS and nutrient exports from pine plantations, primarily through reduced drainage outflows. DA - 1998/// PY - 1998/// DO - 10.2134/jeq1998.00472425002700040029x VL - 27 IS - 4 SP - 923-935 SN - 0047-2425 ER - TY - JOUR TI - Calcium alleviation of hydrogen and aluminum inhibition of soybean root extension from limed soil into acid subsurface solutions AU - Sanzonowicz, C AU - Smyth, TJ AU - Israel, DW T2 - JOURNAL OF PLANT NUTRITION AB - Abstract Alleviation by calcium (Ca) of inhibition of soybean [Glycine max (L.) Merr. cv. ‘Ransom'] root elongation by hydrogen (H) and aluminum (Al) was evaluated in a vertical split‐root system. Roots extending from a limed and fertilized soil compartment grew for 12 days into a subsurface compartment containing nutrient solution with treatments consisting of factorial combinations of either pH (4.0, 4.6, and 5.5) and Ca (0.2, 2.0, 10, and 20 mM), Al (7.5, 15, and 30 μM) and Ca (2.0,10, and 20 mM) at pH 4.6, or Ca (2, 7, and 12 mM) levels and counter ions (SO4 and Cl) at pH 4.6 and 15 μM Al. Length of tap roots and their laterals increased with solution Ca concentration and pH value, but decreased with increasing Al level. Length of both tap and lateral roots were greater when Ca was supplied as CaSO4 than as CaCl2, but increasing Ca concentration from 2 to 12 mM had a greater effect on alleviating Al toxicity than Ca source. In the absence of Al, relative root length (RRL) of tap and lateral roots among pH and Ca treatments was related to the Ca:H molar activity ratio of solutions (R2≥0.82). Tap and lateral RRL among solutions with variable concentrations of Al and Ca at pH 4.6 were related to both the sum of the predicted activities of monomeric Al (R2≥0.92) and a log‐transformed and valence‐weighted balance between activities of Ca and selected monomeric Al species (R2≥0.95). In solutions with 15 μM Al at pH 4.6, response of tap and lateral RRL to variable concentrations of CaSO4 and CaCl2 were related to predicted molar activity ratios of both Ca:Al3+ (R2≥0.89) and Ca:3 monomeric Al (R2≥0.90), provided that AISO4 and AI(SO4)2 species were excluded from the latter index. In all experiments H and Al inhibited length of lateral roots more than tap roots, and a greater Ca:H or Ca:Al concentration ratio was required in solutions to achieve similar RRL values as tap roots. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365442 VL - 21 IS - 4 SP - 785-804 SN - 0190-4167 ER - TY - JOUR TI - Barnyardgrass (Echinochloa crus-galli) control in dry-seeded rice (Oryza sativa) with soil-applied and postemergence herbicide programs AU - Jordan, DL AU - Miller, DK AU - Crawford, SH T2 - WEED TECHNOLOGY AB - A study was conducted from 1994 through 1996 to evaluate barnyardgrass control, rice yield, and estimated economic returns with delayed preemergence (DPRE) applications of pendimethalin, quinclorac, thiobencarb, pendimethalin plus quinclorac, and pendimethalin plus thiobencarb applied alone or followed by postemergence (POST) applications of propanil or propanil plus molinate. Late-season barnyardgrass control with pendimethalin plus quinclorac was greater than with pendimethalin, quinclorac, thiobencarb, or pendimethalin plus thiobencarb. Control with pendimethalin, quinclorac, and pendimethalin plus thiobencarb exceeded that with thiobencarb. Propanil plus molinate controlled barnyardgrass more effectively than propanil. Quinclorac and pendimethalin plus quinclorac were the only DPRE herbicide treatments where yield and estimated economic returns were not improved by POST herbicides. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00042597 VL - 12 IS - 1 SP - 69-73 SN - 0890-037X KW - molinate, S-ethyl hexahydro-1H-azepine-1-carbothioate KW - pendimethalin, N-(1-ethyl-propyl)-3,4-dimethyl-2,6-dinitrobenzenamine KW - propanil, N-(3,4-dichlorophenyl)propanamide KW - quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid KW - thiobencarb, S-[(4-chlorophenyl)methyl]diethyl-carbamothioate KW - barnyardgrass, Echinochloa crus-galli (L.) Beauv. #(3) ECHCG KW - estimated economic return KW - weed management KW - pendimethalin KW - propanil KW - molinate KW - quinclorac KW - thiobencarb KW - ECHCG ER - TY - JOUR TI - Using spontaneous antibiotic-resistant mutants to assess competitiveness of bradyrhizobial inoculants for nodulation of soybean AU - Ramirez, ME AU - Israel, DW AU - Wollum, AG T2 - CANADIAN JOURNAL OF MICROBIOLOGY AB - Spontaneous mutants (3/parental strain) of soybean bradyrhizobia resistant to streptomycin and erythromycin were selected from strains isolated from bradyrhizobial populations indigenous to Cape Fear and Dothan soils. These were used to evaluate (i) the validity of using antibiotic-resistant mutants to make inferences about the competitiveness of parental strains in soil environments and (ii) the recovery of strains in nodules after inoculation of soybeans grown in soils with indigenous bradyrhizobial populations. Streptomycin and erythromycin resistances of all mutants were stable after approximately 27 generations of growth in yeast extract - mannitol medium, but 33% of the mutants lost resistance to erythromycin upon passage through nodules. Only 17% of the mutants were as competitive as their parental strain when inoculated in a ratio near 1:1 in vermiculite. Four of 10 mutants, which differed in competitiveness from their parental strain in vermiculite, had competitiveness against the soil populations equal to that of their parental strain. Therefore, assessment of competitiveness of mutants and parental strains in non-soil media may not accurately reflect their competitiveness in soil systems. For both the Cape Fear and Dothan soils, recovery of a given mutant from nodules of field-grown plants was always lower than from nodules of plants grown in the greenhouse. Inoculation of the entire rooting zone in the greenhouse experiment and of only a portion of the rooting zone in the field experiments may account for this difference in recovery. Techniques that increase the volume of soil inoculated may enhance nodulation by inoculant strains.Key words: Bradyrizobium, antibiotic resistance, competition. DA - 1998/8// PY - 1998/8// DO - 10.1139/cjm-44-8-753 VL - 44 IS - 8 SP - 753-758 SN - 0008-4166 KW - Bradyrhizobium KW - antibiotic resistance KW - competition ER - TY - JOUR TI - Introduction to the environment and vegetation of the southern Blue Ridge province AU - Pittillo, J. D. AU - Hatcher, R. D. AU - Buol, S. W. T2 - Castanea DA - 1998/// PY - 1998/// VL - 63 IS - 3 SP - 202-216 ER - TY - JOUR TI - Hydrogen and aluminum inhibition of soybean root extension from limed soil into acid subsurface solutions AU - Sanzonowicz, C AU - Smyth, TJ AU - Israel, DW T2 - JOURNAL OF PLANT NUTRITION AB - Abstract Soybean [Glycine max (L.) Merr. cv. ‘Ransom'] root elongation under varying concentrations of solution hydrogen (H) and aluminum (Al) was investigated in a vertical split‐root system. Roots extending from a limed and fertilized soil compartment grew for 12 days into a subsurface compartment with solutions adjusted to either different pH values from 3.7 to 5.5 or a factorial combination of pH (4.0,4.6, and 5.2) and Al (0,7.5, 15, and 30 μM) levels. Ionic forms of Al were estimated with GEOCHEM and solution Al was determined with ferron. Boron (B) (18.5 μM) and zinc (Zn) (0.5 μM) were supplied to all solution treatments, in addition to 2000 μM Ca, after preliminary studies at pH 5.2 without Al indicated that their omission inhibited length of tap roots and their laterals in the subsurface compartment. Both H+ and Al inhibited the length of lateral roots more than tap roots. Lateral roots failed to develop on tap roots at pH<4.3 or in treatments with 30 μM Al. Relative tap root length (RRL) among treatments receiving Al correlated with Al as measured by reaction with ferron for 30s. Ferron‐reactive Al was correlated to GEOCHEM‐predicted Al3+ activity (r=0.99). A 50% reduction in RRL occurred with either 2.1 μM Al3+ activity or 4.9 uM ferron‐reactive Al. The absence of shoot and soil‐root biomass differences among solution treatments in the split‐root system indicated that differences in root growth in the subsurface compartment were not directly confounded with differences in top growth. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365410 VL - 21 IS - 2 SP - 387-403 SN - 0190-4167 ER - TY - JOUR TI - Rice (Oryza sativa) response to clomazone AU - Jordan, D. L. AU - Bollich, P. K. AU - Burns, A. B. AU - Walker, D. M. T2 - Weed Science DA - 1998/// PY - 1998/// VL - 46 IS - 3 SP - 374-380 ER - TY - JOUR TI - Registration of 'Apollo' soybean AU - Diers, B. W. AU - Isleib, T. G. AU - Sneller, C. H. T2 - Crop Science AB - Crop ScienceVolume 38, Issue 5 cropsci1998.0011183X003800050050x p. 1400-1401 Registration of Cultivars Registration of ‘Apollo’ Soybean B. W. Diers, B. W. DiersSearch for more papers by this authorT. G. Isleib, T. G. IsleibSearch for more papers by this authorC. H. Sneller, C. H. SnellerSearch for more papers by this author B. W. Diers, B. W. DiersSearch for more papers by this authorT. G. Isleib, T. G. IsleibSearch for more papers by this authorC. H. Sneller, C. H. SnellerSearch for more papers by this author First published: 01 September 1998 https://doi.org/10.2135/cropsci1998.0011183X003800050050xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume38, Issue5September–October 1998Pages 1400-1401 RelatedInformation DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183x003800050050x VL - 38 IS - 5 SP - 1400-1401 ER - TY - JOUR TI - Phosphorylated nitrate reductase and 14-3-3 proteins - Site of interaction, effects of ions, and evidence for an AMP-binding site on 14-3-3 proteins AU - Athwal, GS AU - Huber, JL AU - Huber, SC T2 - PLANT PHYSIOLOGY AB - The inactivation of phosphorylated nitrate reductase (NR) by the binding of 14-3-3 proteins is one of a very few unambiguous biological functions for 14-3-3 proteins. We report here that serine and threonine residues at the +6 to +8 positions, relative to the known regulatory binding site involving serine-543, are important in the interaction with GF14omega, a recombinant plant 14-3-3. Also shown is that an increase in ionic strength with KCl or inorganic phosphate, known physical effectors of NR activity, directly disrupts the binding of protein and peptide ligands to 14-3-3 proteins. Increased ionic strength attributable to KCl caused a change in conformation of GF14omega, resulting in reduced surface hydrophobicity, as visualized with a fluorescent probe. Similarly, it is shown that the 5' isomer of AMP was specifically able to disrupt the inactive phosphorylated NR:14-3-3 complex. Using the 5'-AMP fluorescent analog trinitrophenyl-AMP, we show that there is a probable AMP-binding site on GF14omega. DA - 1998/11// PY - 1998/11// DO - 10.1104/pp.118.3.1041 VL - 118 IS - 3 SP - 1041-1048 SN - 0032-0889 ER - TY - JOUR TI - Mehlich-3 phosphorus buffer coefficients AU - Sobral, LF AU - Aquino, BF AU - Cox, FR T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Phosphorus (P) fertilizer recommendations can be improved if the amount of P required to raise the soil test to a desired value is known. The objective of this study was to determine the increase in soil test P per unit of applied P, the P buffer coefficient, in the laboratory by various means and to compare those values with P buffer coefficients from field data. Phosphorus was applied to soils with predominately kaolinitic mineralogy. The mixtures were then incubated for either 180 and 120 d with numerous drying cycles, or for 7 d and 16 h with either one drying cycle or maintained moist. The samples were extracted with the Mehlich‐3 solution and the change in extractable P per unit of applied P was calculated and termed the Mehlich‐3 P buffer coefficient (M3PBC). The M3PBC varied widely among soils, but was linear within the range of 0 to 300 μg P cm‐3 applied for each. The M3PBC decreased with an increase in time, markedly between 16 h and 7 d, then more slowly from 7 d to 180 d. Drying also reduced the M3PBC, especially on the coarser textured soils. Mehlich‐3 P buffer coefficients from ten field studies were related to the laboratory M3PBC values from dried samples. The prediction of Field M3PBC from the 180‐d M3PBC was linear, while those for the 7‐d and 16‐h M3PBC were quadratic. As time is critical in routine analysis, the 16‐h, dried method was selected as most practical. A prediction equation was calculated to estimate the Field M3PBC from the results of the 16‐h, dried method. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809370065 VL - 29 IS - 11-14 SP - 1751-1761 SN - 0010-3624 ER - TY - JOUR TI - Mapping the root-knot nematode resistance gene (Rk) in tobacco with RAPD markers AU - Yi, HY AU - Rufty, RC AU - Wernsman, EA AU - Conkling, MC T2 - PLANT DISEASE AB - Random amplified polymorphic DNA (RAPD) analysis was conducted to map the Rk gene in tobacco which conditions resistance to races 1 and 3 of the root-knot nematode, Meloidogyne incognita. Resistant burley tobacco genotype NC 528, containing the Rk gene, and the susceptible cultivar Ky 14 were screened with 1,500 random decamers. A low rate of genetic polymor-phism (<10%) was detected among these lines. Two populations (F 1 and F 3 ) of maternally de-rived doubled haploid (MDH) lines of burley tobacco, developed from the cross NC 528 × Ky 14, were used to map the Rk gene. NC 528, Ky 14, three Rk-resistant (Rk-R) DNA bulks, andthree Rk-susceptible (Rk-S) bulks generated from F 1 -derived MDH individuals were screenedwith the primers that amplified bands polymorphic between Rk-R and Rk-S lines. A total of 67 F1MDH lines and 59 F3MDH lines were screened with the primers that amplified bands polymorphic between Rk-R bulks and Rk-S bulks to confirm linkage between candidate markers and the Rk gene. Sixteen RAPD markers were positioned at six loci in a map 24.1 centimorgans long. Six RAPD markers, including one identified in the F3MDH population, were mapped at the Rk locus. DA - 1998/12// PY - 1998/12// DO - 10.1094/PDIS.1998.82.12.1319 VL - 82 IS - 12 SP - 1319-1322 SN - 0191-2917 KW - disease resistance KW - linkage analysis KW - Meloidogyne incognita KW - Nicotiana tabacum ER - TY - JOUR TI - Fiber yield and quality of cotton grown at two divergent population densities AU - Jones, MA AU - Wells, R T2 - CROP SCIENCE AB - Poor seed germination and early seedling damage often reduce plant populations in the north‐eastern cotton ( Gossypium hirsutum L.) producing region of the USA. A field study was conducted at Clayton, NC, on a Dothan sandy loam (fine‐loamy, siliceous, thermic Plinthic Kandiudult) to investigate responses of cotton reproductive development to reduced plant population. All flowers on plants grown at 2 and 12 plants m −2 were tagged so that associations among boll and lint quantity and quality, flowering date, and fruiting position could be determined. On plants grown at 2 plants m −2 , 33 and 65% of their fiber came from flowers initiated before 88 days after planting (DAP) in 1992 and 1993, respectively. Plants grown at 12 plants m −2 produced 63 and 88% of their fiber from flowers initiated before 88 DAP in 1992 and 1993, respectively. Plant population did not affect total lint yield, however. Because of favorable late‐season weather, plants grown at 2 plants m −2 produced more bolls on vegetative branches and at more distal sympodial positions than did plants grown at 12 plants m −2 . Boll weight and micronaire were generally higher for earlier bolls at all positions for the lower population density. Later bolls exhibited poorer boll and fiber properties, indicating negative effects of reduced heat unit accumulation by later bolls. Our findings indicate that replanting, which might delay stand establishment by 3 to 4 wk, would be of little help toward improving fiber yield because it would rely more heavily on later produced bolls. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800050013x VL - 38 IS - 5 SP - 1190-1195 SN - 0011-183X ER - TY - JOUR TI - Division S-7 - Forest & range soils - Bromide transport under contour hedgerow systems in sloping oxisols AU - Agus, F AU - Cassel, DK AU - Garrity, DP T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Abstract Contour hedgerows promote infiltration, thereby reducing runoff and soil erosion on sloping lands. The increase in infiltration could increase the leaching of mobile chemicals. The objective of this study was to determine the effect of hedgerows on Br ‐ transport in two Hapludox soils with 21 to 30% slope in the Philippines. In Exp. 1, KBr at the rate of 200 kg Br ‐ ha ‐1 was broadcast in June 1991 at corn ( Zea mays L.) planting on (i) the alleyways of plots with pruned hedgerows of Gliricidia sepium (Jacq.) Klunth ex Walp. and paspalum ( Paspalum conjugatum Bergius) (hedgerow treatment) and (ii) open field plots (control). In Exp. 2, KBr was applied at the same rate as in 1991 in strips in the hedgerow and control plots that had not received the KBr application the previous year. After Br ‐ application, Br ‐ was analyzed in hand‐augered soil samples at increments to 105 cm and in soil solution samples taken with suction lysimeters at the 30‐, 60‐, and 90‐cm depths. Estimated pools of Br ‐ (kg ha ‐1 ) at a given depth were usually less for the suction lysimeter than for soil samples, possibly due to percolating water bypassing Br ‐ in soil aggregates above the depth of lysimeter sampling. After about 500 mm of rainfall, 50% of the Br ‐ had leached below the 30‐cm depth in the hedgerow plots. Slightly greater lateral, but less vertical, Br ‐ movement occurred for the control. If NO 3 leaches to or below the observed Br ‐ leaching depths, it would become unavailable to acidsensitive food crops displaying shallow rooting depths. DA - 1998/// PY - 1998/// DO - 10.2136/sssaj1998.03615995006200040027x VL - 62 IS - 4 SP - 1042-1048 SN - 1435-0661 ER - TY - JOUR TI - Assessment of rhizotoxic aluminum in soil solutions by computer and chromogenic speciation AU - Jallah, JK AU - Smyth, TJ T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS AB - Abstract Numerous chemical species of aluminum (Al) occur in acid soils and simple but accurate methods are needed to characterize phytotoxicity. Kinetic reaction studies between Al and ferron were used to separate Al into instantaneously reactive (Ala), metastable (Alb), and non‐reactive (Alc) fractions in soil solutions of two North Carolina Ultisols. Relative root growth of field‐grown corn (Zea mays L.) was used to assess rhizotoxicity of kinetically measured Al forms. Reaction of Alb with ferron conformed to first order kinetics, with rate constant values ranging from 0.53 to 9.13 minute‐1. The Ala fraction correlated significantly with Al reacting in 30 seconds (r2=0.99), but the former averaged 10% less than the latter. Both Ala and Al reacting in 30 seconds correlated significantly with the Alb fraction (r2≥0.89), but not with the Alc fraction (r2<0.1). Correlation exercises between ferronreactive Al fractions and various Al species predicted by the GEOCHEM‐PC speciation program revealed a strong relationship between Ala and the sum of activities of Al3+, Al(OH)2+, and A1(OH)2 +, suggesting an instantaneous reaction of these species with ferron. The Ala and Ab fractions correlated significantly with root growth. The Alc fraction did not correlate significantly with root growth and may be relatively less toxic. Further soil solution studies may be required to ascertain the nature of actual Al species measured in the Ala and Ab fractions. DA - 1998/// PY - 1998/// DO - 10.1080/00103629809369927 VL - 29 IS - 1-2 SP - 37-50 SN - 1532-2416 ER - TY - JOUR TI - Identification of a novel isoform of the chloroplast-coupling factor alpha-subunit AU - Burkey, KO AU - Mathis, JN T2 - PLANT PHYSIOLOGY AB - Studies were conducted to identify a 64-kD thylakoid membrane protein of unknown function. The protein was extracted from chloroplast thylakoids under low ionic strength conditions and purified to homogeneity by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Four peptides generated from the proteolytic cleavage of the wheat 64-kD protein were sequenced and found to be identical to internal sequences of the chloroplast-coupling factor (CF1) alpha-subunit. Antibodies for the 64-kD protein also recognized the alpha-subunit of CF1. Both the 64-kD protein and the 61-kD CF1 alpha-subunit were present in the monocots barley (Hordeum vulgare), maize (Zea mays), oat (Avena sativa), and wheat (Triticum aestivum); but the dicots pea (Pisum sativum), soybean (Glycine max Merr.), and spinach (Spinacia oleracea) contained only a single polypeptide corresponding to the CF1 alpha-subunit. The 64-kD protein accumulated in response to high irradiance (1000 mumol photons m-2 s-1) and declined in response to low irradiance (80 mumol photons m-2 s-1) treatments. Thus, the 64-kD protein was identified as an irradiance-dependent isoform of the CF1 alpha-subunit found only in monocots. Analysis of purified CF1 complexes showed that the 64-kD protein represented up to 15% of the total CF1 alpha-subunit. DA - 1998/2// PY - 1998/2// DO - 10.1104/pp.116.2.703 VL - 116 IS - 2 SP - 703-708 SN - 0032-0889 ER - TY - JOUR TI - Apoplastic sugars, fructans, fructan exohydrolase, and invertase in winter oat: Responses to second-phase cold hardening AU - Livingston, DP AU - Henson, CA T2 - PLANT PHYSIOLOGY AB - Abstract Changes in apoplastic carbohydrate concentrations and activities of carbohydrate-degrading enzymes were determined in crown tissues of oat (Avena sativa L., cv Wintok) during cold hardening. During second-phase hardening (−3°C for 3 d) levels of fructan, sucrose, glucose, and fructose in the apoplast increased significantly above that in nonhardened and first-phase-hardened plants. The extent of the increase in apoplastic fructan during second-phase hardening varied with the degree of fructan polymerization (DP) (e.g. DP3 and DP4 increased to a greater extent than DP7 and DP &gt; 7). Activities of invertase and fructan exohydrolase in the crown apoplast increased approximately 4-fold over nonhardened and first-phase-hardened plants. Apoplastic fluid extracted from nonhardened, first-phase-hardened, and second-phase-hardened crown tissues had low levels, of symplastic contamination, as determined by malate dehydrogenase activity. The significance of these results in relation to increases in freezing tolerance from second-phase hardening is discussed. DA - 1998/1// PY - 1998/1// DO - 10.1104/pp.116.1.403 VL - 116 IS - 1 SP - 403-408 SN - 1532-2548 ER - TY - JOUR TI - Annual grass control by glyphosate plus bentazon, chlorimuron, fomesafen, or imazethapyr mixtures AU - Gimenez, AE AU - York, AC AU - Wilcut, JW AU - Batts, RB T2 - WEED TECHNOLOGY AB - The isopropylamine salt of glyphosate at 420, 560, and 840 g ae/ha applied alone or mixed with the sodium salt of bentazon at 840 g ai/ha, chlorimuron at 9 g ai/ha, the sodium salt of fomesafen at 350 g ai/ha, or the ammonium salt of imazethapyr at 70 g ae/ha was evaluated for control of large crabgrass and broadleaf signalgrass. Neither grass was controlled by bentazon, fomesafen, or chlorimuron. Imazethapyr controlled large crabgrass and broadleaf signalgrass 30 and 72%, respectively, 3 weeks after treatment (WAT). Glyphosate at all rates controlled both grasses 100%. Control 3 WAT was unaffected by mixing bentazon, chlorimuron, fomesafen, or imazethapyr with glyphosate. Broadleaf signalgrass control 1 WAT was reduced 4 to 15% by mixing bentazon with glyphosate. DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x0004269x VL - 12 IS - 1 SP - 134-136 SN - 0890-037X KW - bentazon, 3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide KW - chlorimuron, 2-[[[[(4-chloro-6-methoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]benoic acid KW - fomesafen, 5-[2-chloro-4-(trifluoromethyl)phenoxy]-N-(methylsulfonyl)-2-nitrobenzamide KW - glyphosate, N-(phosphonomethyl)glycine KW - imazethapyr, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid KW - broadleaf signalgrass, Brachiaria platyphylla (Griseb.) Nash #(3) BRAPP KW - large crabgrass, Digitaria sanguinalis (L.) Scop. # DIGSA KW - herbicide mixtures KW - postemergence weed control KW - Brachiaria platyphylla KW - Digitaria sanguinalis KW - BRAPP KW - DIGSA ER - TY - PCOMM TI - A comparison of the contributions of clay, silt, and organic matter to the effective CEC of soils in sub-Saharan Africa AU - Buol, S AU - Kamprath, EJ DA - 1998/6// PY - 1998/6// DO - 10.1097/00010694-199806000-00009 SP - 508-508 ER - TY - JOUR TI - Tracing nitrogen movement in corn production systems in the North Carolina Piedmont: A nitrogen-15 study AU - Crozier, CR AU - King, LD AU - Volk, RJ T2 - AGRONOMY JOURNAL AB - Abstract Legume cover crops have been studied in the southeastern USA, but there have been no 15 N tracer studies comparing movement of legume N and fertilizer N for this region. Our study used l5 N‐enriched crimson clover ( Trifolium incarnatum L.) (135 kg N ha −1 ) and either 15 NH 4 NO 3 or NH 15 4 NO 3 (70 kg total N ha −1 ) to quantify N movement through soil inorganic and organic N pools and into corn ( Zea mays L.). Clover N mineralized rapidly, with 45% of the initially applied N detectable as inorganic N at 18 d following incorporation. Rapid nitrification of enriched NH + 4 occurred, but, since the soil NO ‐ 3 pool was larger in this treatment than in the enriched NO ‐ 3 treatment (presumably due to chance), the relative enrichment of the soil NO ‐ 3 pool was less than with the application of enriched NO ‐ 3 . At anthesis, 25% of the N in corn had been derived from the NO ‐ 3 source, while only 11% had been derived from the NH + 4 source (P < 0.05). At physiological maturity in 1990, the first growing season, 38 to 44% of each enriched source could be accounted for. By physiological maturity in 1991, 60% of the clover source but only 28 to 36% of the fertilizer sources could be accounted for. This study demonstrates the substantial amounts of endogenous soil N mineralization, inorganic N immobilization, and legume N persistence in these cropping systems. DA - 1998/// PY - 1998/// DO - 10.2134/agronj1998.00021962009000020009x VL - 90 IS - 2 SP - 171-177 SN - 0002-1962 ER - TY - JOUR TI - Reduced chemical input cropping systems in the southeastern United States. III, Economic analysis AU - King, L. D. AU - Hoag, D. T2 - American Journal of Alternative Agriculture AB - Abstract This study evaluated the profitability of several cropping systems during a 10-year period of an experiment comparing rotations and levels of purchased inputs. Continuous corn or sorghum, corn/wheat-soybean (2-year), and corn/wheat-soybean/corn/clover hay (4-year) were managed with recommended fertilizer and pesticide rates and no-till planting (C) or with N from legumes, conventional tillage, and cultivation for weed control (L). Medium input management (M: medium rate of N and banded herbicides) was included during years 5 through 10. Generally, corn was the least profitable crop, regardless of input level or type of rotation. Rotating crops improved profit more than did adding inputs to continuous corn. With L, average annual profit was: continuous corn, -$64/ha; 2-year rotation, $135/ha; and 4-year rotation, $158/ha. With C, the 2-year rotation increased profit to $165/ha from -$119/ha with continuous corn. The increased profit with rotations was due to greater profits from wheat, soybean, and hay offsetting low or negative profit from corn. Sorghum (grown only in monoculture) was more profitable with L ($34/ha) than with C (-$20/ha). During the 6 years when all input levels were compared, the order of average profit was M>L>C with continuous corn. Generally, profit was not increased by M compared with L in the 2-and 4-year rotations. With L, the cost of weed control was 20% of that for C with corn and 44% with soybean. Cost of N from fertilizer was $0.66/kg, but cost of N from crimson clover (seed and planting costs) averaged $0.92/kg when clover was drilled, $1.27/kg when aerially seeded, and $0.16/kg when naturally reseeded. DA - 1998/// PY - 1998/// DO - 10.1017/s088918930000758x VL - 13 IS - 1 SP - 12-27 ER - TY - CHAP TI - Red and lateritic soils of the world: Concept, potential, constraints, and challenges AU - Buol, S. W. AU - Cook, M. G. T2 - Red & lateritic soils A2 - J. Sehgal, W. E. Blum A2 - K. S. Gajbhiye, K. S. CN - S592.17.R43 R42 1998 PY - 1998/// SP - 49-56 PB - Rotterdam: Brookfield ER - TY - JOUR TI - RFLP tagging of QTLs conditioning specific leaf weight and leaf size in soybean AU - Mian, MAR AU - Wells, R AU - Carter, TE AU - Ashley, DA AU - Boerma, HR T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/3// PY - 1998/3// DO - 10.1007/s001220050748 VL - 96 IS - 3-4 SP - 354-360 SN - 0040-5752 KW - soybean KW - Glycine max KW - QTL KW - RFLP KW - SLW KW - leaf size ER - TY - JOUR TI - Potential uses of sicklepod (Cassia obtusifolia) AU - Abbott, TP AU - Vaughn, SF AU - Dowd, PF AU - Mojtahedi, H AU - Wilson, RF T2 - INDUSTRIAL CROPS AND PRODUCTS AB - Sicklepod (Cassia obtusifolia) is a leguminous weed species that has become a severe problem in soybean production throughout the Southern United States. Economic incentives, such as premiums for low levels of foreign matter from cleaning soybeans prior to sale, could generate a large source of sicklepod seed in that area. This study was undertaken to evaluate C. obtusifolia seed for potential applications. As much as 41% of the seed was extractable. Some extracts were strong inhibitors of wheat, velvetleaf and sicklepod root growth, causing discoloration of the root meristems in a manner similar to that caused by naphthoquinones such as juglone and plumbagin. Some extracts increased weight gain in fall armyworm (Spodoptera frugiperda) causing them to grow to 50–100% larger than controls in a 7-day trial. Survival of Columbia root-knot nematode (Meloidogyne chitwoodi) in the soil was inversely correlated to the amount of ground whole sicklepod amendment. No phytotoxic effects of the meal amendment on tomato plants or inhibition of germination for several crop seeds was observed at the levels tested. DA - 1998/3// PY - 1998/3// DO - 10.1016/S0926-6690(97)10010-3 VL - 8 IS - 1 SP - 77-82 SN - 0926-6690 KW - sicklepod KW - Cassia obtusifolia KW - gum KW - nematode KW - inhibitor KW - fall armyworm KW - Allelochemical KW - Spodoptera frugiperda KW - Meloidogyne chitwoodi KW - soil amendment ER - TY - JOUR TI - Influence of pyrithiobac sodium on purple (Cyperus rotundus) and yellow nutsedge (C-esculentus) AU - Wilcut, J. W. T2 - Weed Science DA - 1998/// PY - 1998/// VL - 46 IS - 1 SP - 111-115 ER - TY - JOUR TI - Characterization of a fructan exohydrolase purified from barley stems that hydrolyzes multiple fructofuranosidic linkages AU - Henson, CA AU - Livingston, DP T2 - PLANT PHYSIOLOGY AND BIOCHEMISTRY AB - Barley (Hordeum vulgare cv Morex) fructan exohydrolase (EC 3.2.1.80) was purified by precipitation with ammonium sulfate and chromatography on anion exchange and lectin affinity columns. The final enzyme preparation was homogenous as determined by the presence of a single band on silver stained SDS-PAGE and IEF gels. The purified protein had a molecular mass of 33 kDa and a pI of 7.8. Analyses of relative hydrolytic rates of various fructans were determined by measuring released fructose by pulsed electrochemical detection after separation of reactions by HPLC. The purified enzyme hydrolyzed β-2,1-linkages in 6G, 1-kestotetraose, 1 and 6G-kestotetraose, 1, 1-kestotetraose, and 1-kestotriose with relative rates of 100 : 96 : 85 : 88. This enzyme slowly hydrolyzed the β-2,6-linkages in 6G-kestotriose and in 6G, 6-kestotetraose and sucrose with relative rates of 5 : 4 : 3 compared to 6G, 1-kestotetraose hydrolysis rates arbitrarily set at 100. The substrate attack pattern, determined by identifying products from hydrolysis of purified fructan tetrasaccharides, was of the multichain type. Sucrose was a mixed-type inhibitor of inulin hydrolysis. DA - 1998/10// PY - 1998/10// DO - 10.1016/S0981-9428(98)80021-1 VL - 36 IS - 10 SP - 715-720 SN - 0981-9428 KW - carbohydrate metabolism KW - beta-fructofuranoside fructohydrolase KW - inulinase KW - invertase KW - Hordeum vulgare ER - TY - JOUR TI - Inheritance of resistance to southern corn rust in tropical by corn-belt maize populations AU - Holland, JB AU - Uhr, DV AU - Jeffers, D AU - Goodman, MM T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/2// PY - 1998/2// DO - 10.1007/s001220050732 VL - 96 IS - 2 SP - 232-241 SN - 0040-5752 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031956880&partnerID=MN8TOARS KW - Puccinia polysora KW - RFLP markers KW - partial resistance ER - TY - JOUR TI - Influence of ozone stress on soybean response to carbon dioxide enrichment: III. Yield and seed quality AU - Heagle, AS AU - Miller, JE AU - Pursley, WA T2 - CROP SCIENCE AB - Ozone in the troposphere can cause plant stress, whereas elevated CO 2 generally causes positive responses. Little is known of how these gases interact to affect plant response. Interactive effects on yield and seed quality of soybean [ Glycine max (L.) Merr.] grown in 14‐L pots were measured in open‐top field chambers. Essex was tested in 1993, and Essex, Holladay, and NK 6955 were tested in 1994. Plants were exposed from emergence to maturity to four CO 2 levels (ambient and 1.3,1.6, and 2.0 times ambient) and three O 3 levels (0.4, 0.9, and 1.5 times ambient) in 12 combinations. Increasing O 3 suppressed growth and yield, whereas CO 2 enrichment stimulated growth and yield. Carbon dioxide‐induced stimulation was greater for plants stressed by O 3 than for non stressed plants. For example, CO 2 at 2.0 times ambient increased 2‐yr mean seed yield of Essex by 16, 24, and 81% at O 2 levels of 0.4, 0.9, and 1.5 times ambient, respectively. Effects of O 3 and CO 2 on seed oil content were variable with numerous cultivar differences. Seed protein content was never affected. Elevated O 3 suppressed oleic acid content in seeds, whereas CO 2 increased it; the nature of the O 3 × CO 2 interaction for oleic acid was similar to that observed for most yield measures. Carbon dioxide‐induced stimulation of plants stressed by O 3 was apparently caused partly by amelioration of O 3 stress. Interactions between O 3 and CO 2 must be considered for proper interpretation of cause‐effect relationships in CO 2 , enrichment studies. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800010022x VL - 38 IS - 1 SP - 128-134 SN - 0011-183X ER - TY - JOUR TI - Influence of ozone stress on soybean response to carbon dioxide enrichment: II. Biomass and development AU - Miller, JE AU - Heagle, AS AU - Pursley, WA T2 - CROP SCIENCE AB - Previous research has shown that elevated CO 2 concentrations can increase plant growth, whereas the air pollutant O 3 is phytotoxic. Because elevated concentrations of these gases will co‐occur, the objective of our experiment was to determine if estimates of plant growth response to future levels of CO 2 and O 3 require experiments to test the gases in combination. Soybean plants [ Glycine max (L.) Merr. cv. Essex) were exposed in open‐top chambers to combinations of O 3 and CO 2 from plant emergence through physiological maturity. Ozone treatments were charcoal‐filtered air (CF), nonfiltered air (NF), and NF with O 3 added for 12 d −1 (NF+) (seasonal mean 12 d −1 O 3 concentrations of 20, 50, or 79 nL L −1 , respectively). Carbon dioxide exposures were for 24 h d −1 giving seasonal mean 12 d −1 concentrations of 370, 482, 599, or 713 μL L −1 . Over the season, elevated CO 2 usually stimulated growth and O 3 suppressed growth. Elevated CO 2 usually increased partitioning of biomass to branches, decreased partitioning to pods, increased specific leaf weight, and decreased leaf area ratio. Ozone suppressed leaf and root weight ratios, increased pod weight ratios, and decreased specific leaf weight. Toward the end of the season, both O 3 and CO 2 accelerated reproductive development. Elevated CO 2 moderated suppression of growth by O 3 , and the highest CO 2 concentration completely ameliorated O 3 effects on main stem biomass, root biomass, and leaf area. Ozone, however, limited some positive growth responses to CO 2 , especially at less than a doubling of CO 2 concentrations. These results indicate that in order to understand the future impacts of atmospheric gases such as elevated CO 2 and O 3 on crop growth, their combined effects should be determined. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800010021x VL - 38 IS - 1 SP - 122-128 SN - 0011-183X ER - TY - JOUR TI - Influence of ozone stress on soybean response to carbon dioxide enrichment: I. Foliar properties AU - Heagle, AS AU - Miller, JE AU - Booker, FL T2 - CROP SCIENCE AB - Tropospheric O 3 can cause foliar injury, decreased growth, and decreased yield, whereas CO 2 enrichment generally causes opposite effects. Little is known about plant response to mixtures of O 3 and CO 2 . Open‐top field chambers were used to determine if foliar responses of soybean [ Glycine max (L.) Merr.] to CO 2 enrichment are affected by O 3 stress and vice versa. Plants were grown in 14‐L pots and exposed to four CO 2 and three O 3 concentrations in 12 combinations. The CO 2 treatments were ambient (366 μL − ) and three treatments with CO 2 added for 24 h d 1 at approximately 1.3, 1.6, and 2.0 times ambient. The O 3 treatments were charcoal‐filtered air (CF), nonfiltered air (NF), and NF with O 3 added for 12 h −1 ( NF+), resulting in seasonal concentrations of approximately 20, 46, and 75 nL L −1 . Foliar effects of CO 2 enrichment were dependent on the amount of stress caused by O 3 . In the CF treatment, plants were not stressed by O 3 , and CO 2 enrichment caused chlorosis and decreased chlorophyll. In the NF and NF+ treatments, plants were stressed by 03, and CO 2 enrichment suppressed chlorosis and increased chlorophyll. Ozone decreased specific leaf weight, increased foliar N and C, and decreased C/N ratios, whereas CO 2 caused opposite responses for these measures. Ozone increased foliar S and B but did not affect P or K concentrations. Conversely, CO 2 enrichment suppressed foliar S, B, P, and K concentrations. These interactions between O 3 and CO 2 emphasize a need to consider the amount of plant stress caused by O 3 in studies to measure effects of CO 2 enrichment. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800010020x VL - 38 IS - 1 SP - 113-121 SN - 0011-183X ER - TY - JOUR TI - Changes in the genetic diversity of cotton in the USA from 1970 to 1995 AU - Van Esbroeck, GA AU - Bowman, DT AU - Calhoun, DS AU - May, OL T2 - CROP SCIENCE AB - Despite concern about genetic vulnerability, little is known about the recent changes in the genetic diversity of upland cotton ( Gossypium hirsutum L.). The objectives of this study were to determine the trends in the genetic diversity of upland cotton in the USA during the last 25 yr and to investigate probable causes for these changes. Two estimates of genetic diversity, coefficient of parentage ( r p ) and field uniformity ( r i ; r p weighted by the proportion of the hectarage occupied), were made for cultivars occupying over 1% of the hectarage within a region (Southeast, South‐central, Southwest, and West) from 1970 to 1995 at 5‐yr intervals. An average of 17 (range = 8–46) cultivars accounted for 97% of the cotton hectarage within a region. Regional r p values were relatively stable at 0.12 to 0.15 from 1970 to 1990 and then sharply increased to 0.20 in 1995. Higher r p values in commonly grown cultivars than in released cultivars indicated that much of the genetic diversity in cotton remains unused by growers. Field uniformity ( r i ) remained at about 0.30 for all regions during the past 25 yr because increases in r p were matched with an increase in the number of cultivars grown and/or a decline in the proportion of the area planted to any single cultivar. The frequent use of several parents for the creation of new cultivars and the planting of only a small portion of the available cultivars has led to a high level of genetic uniformity. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800010006x VL - 38 IS - 1 SP - 33-37 SN - 0011-183X ER - TY - JOUR TI - A major gene for powdery mildew resistance transferred to common wheat from wild einkorn wheat AU - Shi, AN AU - Leath, S AU - Murphy, JP T2 - PHYTOPATHOLOGY AB - A major gene for resistance to wheat powdery mildew (Blumeria graminis f. sp. tritici = Erysiphe graminis f. sp. tritici) has been successfully transferred into hexaploid common wheat (Triticum aestivum, 2n = 6x = 42, AABBDD) from wild einkorn wheat (Triticum monococcum subsp. aegilopoides, 2n = 2x = 14, AA). NC96BGTA5 is a germ plasm line with the pedigree Saluda × 3/PI427662. The response patterns for powdery mildew resistance in NC96BGTA5 were tested with 30 differential isolates of B. graminis f. sp. tritici, and the line was resistant to all tested isolates. The analyses of P 1 , P 2 , F 1 , F 2 , and BC 1 F 1 populations derived from NC96BGTA5 revealed two genes for wheat powdery mildew resistance in the NC96BGTA5 line. One gene, Pm3a, was from its recurrent parent Saluda, and the second was a new gene introgressed from wild einkorn wheat. The gene was determined to be different from Pm1 to Pm21 by gene-for-gene and pedigree analyses. The new gene was identified as linked to the Pm3a gene based on the F 2 and BC 1 F 1 populations derived from a cross between NC96BGTA5 and a susceptible cultivar NK-Coker 68-15, and the data indicated that the gene was located on chromosome 1A. It is proposed that this new gene be designated Pm25 for wheat powdery mildew resistance in NC96BGTA5. Three random amplified polymorphic DNA markers, OPX06 1050 , OPAG04 950 , and OPAI14 600 , were found to be linked to this new gene. DA - 1998/2// PY - 1998/2// DO - 10.1094/PHYTO.1998.88.2.144 VL - 88 IS - 2 SP - 144-147 SN - 0031-949X ER - TY - JOUR TI - New weed management programs for weed control in no-till cotton AU - Wilcut, J. W. AU - Hayes, R. AU - Askew, S. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 865 ER - TY - JOUR TI - Influence of adjuvants on efficacy of 2,4-DB, CADRE, and Strongarm AU - Jordan, D. L. AU - Johnson, P. D. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 60-61 ER - TY - JOUR TI - Herbicide programs for red rice (Oryza sativa) control in soybean (Glycine max) AU - Askew, SD AU - Street, JE AU - Shaw, DR T2 - WEED TECHNOLOGY AB - A study was conducted in 1994 and 1995 at two Mississippi locations to evaluate preplant incorporated (PPI) and preemergence (PRE) applications of alachlor, clomazone, SAN 582, metolachlor, pendimethalin, and trifluralin, and postemergence (POST) applications of AC 263,222 and imazethapyr alone or followed by clethodim late postemergence (LPOST) for red rice control in soybean. Applications of 110 g ai/ha clethodim increased red rice control when following any earlier herbicide application at one location that harbored a high natural infestation. In 1 yr at one location, red rice seedhead suppression from PPI and PRE herbicide applications alone was greater than 95% due to high activity from herbicides and drought conditions during red rice seedhead development. Early postemergence (EPOST) applications of 30 g ae/ha AC 263,222 suppressed at least 95% of red rice seedheads, regardless of year, location, or clethodim LPOST application. At one location, any treatment where 110 g/ha clethodim followed an earlier herbicide application suppressed red rice seedheads at least 95%. Compared to the nontreated control, only AC 263,222 injured soybean (30%) and reduced soybean yield (200 kg/ha). DA - 1998/// PY - 1998/// DO - 10.1017/s0890037x00042640 VL - 12 IS - 1 SP - 103-107 SN - 0890-037X KW - AC 263,222, (+/-)-2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-methyl-3-pyridinecarboxylic acid KW - alachlor, 2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide KW - clethodim, (E,E)-(+/-)-2-[1-[[(3-chloro-2-propenyl)oxy]imino]propyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one KW - clomazone, 2-[(2-chlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone KW - SAN 582, 2-chloro-N-[(1-methyl-2-methoxy)ethyl]-N-(2,4-dimethyl-thien-3-yl)-acetamide KW - imazethapyr, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid KW - metolachlor, 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide KW - pendimethalin, N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine KW - trifluralin, 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine KW - red rice, Oryza sativa L. #(3) ORYSA KW - soybean, Glycine max (L.) Merr. 'Hartz 4464' and 'Terra-Vig 5452' KW - seedhead suppression KW - AC 263,222 KW - alachlor KW - clethodim KW - clomazone KW - SAN 582 (proposed dimethenamid) KW - imazethapyr KW - metolachlor KW - pendimethalin KW - trifluralin KW - ORYSA ER - TY - JOUR TI - Buctril and MSMA combinations for sicklepod management in BXN cotton AU - Paulsgrove, M. D. AU - Wilcut, J. W. AU - Hinton, J. D. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 27-28 ER - TY - JOUR TI - Basic genetic research in Gossypium AU - Lee, J. A. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 519-522 ER - TY - JOUR TI - Use of goats as biological agents for the renovation of pastures in the Appalachian region of the United States AU - Luginbuhl, JM AU - Harvey, TE AU - Green, JT AU - Poore, MH AU - Mueller, JP T2 - AGROFORESTRY SYSTEMS DA - 1998/// PY - 1998/// DO - 10.1023/A:1006250728166 VL - 44 IS - 2-3 SP - 241-252 SN - 0167-4366 KW - browse KW - cattle KW - defoliation KW - pasture reclamation KW - Rosa multiflora ER - TY - JOUR TI - The establishment and early growth of three leguminous tree species for use in silvopastoral systems of the southeastern USA AU - Addlestone, BJ AU - Mueller, JP AU - Luginbuhl, JM T2 - AGROFORESTRY SYSTEMS DA - 1998/// PY - 1998/// DO - 10.1023/A:1006254812236 VL - 44 IS - 2-3 SP - 253-265 SN - 0167-4366 KW - Albizia julibrissin KW - browse KW - forage KW - Gleditsia triacanthos KW - goats KW - Robinia pseudo-acacia ER - TY - JOUR TI - Testing of peats for removal of odors from liquid swine manure AU - Rizzuti, AM AU - Cohen, AD AU - Hunt, PG AU - Vanotti, MB T2 - JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING AB - Abstract This paper reports on research designed to investigate the capacities of different kinds of peat to remove odor‐causing compounds from liquid swine manure (LSM). Two experiments were conducted. In experiment #1, five different peat types (both wet and dry) representing a wide range of properties were tested. Eight percent slurries (of peat/LSM) were measured for odor changes at 6, 24, and 96 hours using odor panel and GC/FID analysis. Experiment #2 was designed to determine more precisely the kinds of odor‐causing compounds thatwere changing during treatment. Two extremely different wet peat types were tested in 8 percent slurries after 24 hours of treatment. Odor changes were evaluated using both an odor panel and GC/MS, head‐space, solid‐phase, microextraction (HSM). The GC/FID and odor panel results indicated that wet peats were much more effective in removing odor‐causing compounds from LSM than were dry peats. Wet peats significantly reduced the LSM odor intensity after 6 hours of treatment, and completely eliminated odors after the 24 hour treatment. The results from the GC/MS HSM method (experiment #2) confirmed the results from experiment #1 and also, allowed us to more precisely identify the specific odor‐causing compounds being reduced and to distinguish specific changes in these compounds between peat types. Of the 23 malodorous compounds identified in experiment #2, all showed significant reductions; however, one peat was better at reducing 10 of these, while the wet North Carolina peat was better at reducing 9 others. These results suggest that improvements in odor removal efficiency and costs can be achieved by selection of specific peat types for a specific LSM site. DA - 1998/// PY - 1998/// DO - 10.1080/10934529809376814 VL - 33 IS - 8 SP - 1719-1739 SN - 1532-4117 KW - peat KW - liquid swine manure KW - odor removal KW - hogs ER - TY - JOUR TI - Registration of 'Olympus' soybean AU - Diers, B. W. AU - Isleib, T. G. AU - Sneller, C. H. T2 - Crop Science AB - Crop ScienceVolume 38, Issue 5 cropsci1998.0011183X003800050049x p. 1400-1400 Registration of Cultivars Registration of ‘Olympus’ Soybean B. W. Diers, B. W. DiersSearch for more papers by this authorT. G. Isleib, T. G. IsleibSearch for more papers by this authorC. H. Sneller, C. H. SnellerSearch for more papers by this author B. W. Diers, B. W. DiersSearch for more papers by this authorT. G. Isleib, T. G. IsleibSearch for more papers by this authorC. H. Sneller, C. H. SnellerSearch for more papers by this author First published: 01 September 1998 https://doi.org/10.2135/cropsci1998.0011183X003800050049xCitations: 1AboutPDF 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 onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume38, Issue5September–October 1998Pages 1400-1400 RelatedInformation DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183x003800050049x VL - 38 IS - 5 SP - 1400 ER - TY - JOUR TI - Phosphorus effects on tropical soda apple (Solanum viarum Dunal) growth and development AU - Call, N. M. AU - Coble, H. D. T2 - Proceedings, Southern Weed Science Society DA - 1998/// PY - 1998/// VL - 51 IS - 1998 SP - 244-245 ER - TY - JOUR TI - Nitrification treatment of swine wastewater by encapsulated nitrifiers AU - Vanotti, M. B. AU - Hunt, P. G. T2 - Paper (American Society of Agricultural Engineers) DA - 1998/// PY - 1998/// VL - 98 IS - 4124 SP - 1-10 ER - TY - JOUR TI - My view AU - Coble, H. D. T2 - Weed Science DA - 1998/// PY - 1998/// VL - 46 IS - 5 SP - 509 ER - TY - JOUR TI - Biomass of tomato seedlings exposed to an allelopathic phenolic acid and enriched atmospheric carbon dioxide AU - Shafer, , SR AU - Blum, U AU - Horton, SJ AU - Hesterberg, DL T2 - WATER AIR AND SOIL POLLUTION DA - 1998/8// PY - 1998/8// DO - 10.1023/A:1004944731826 VL - 106 IS - 1-2 SP - 123-136 SN - 0049-6979 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032145076&partnerID=MN8TOARS KW - global change KW - community ecology KW - interference ER - TY - JOUR TI - Nonpoint sources AU - Line, DE AU - McLaughlin, RA AU - Osmond, DL AU - Jennings, GD AU - Harman, WA AU - Lombardo, LA AU - Spooner, J T2 - WATER ENVIRONMENT RESEARCH AB - Water Environment ResearchVolume 70, Issue 4 p. 895-912 Fate and Effect of PollutantFree Access Nonpoint sources Daniel E. Line, Daniel E. LineSearch for more papers by this authorRichard A. McLaughlin, Richard A. McLaughlinSearch for more papers by this authorDeanna L. Osmond, Deanna L. OsmondSearch for more papers by this authorGregory D. Jennings, Gregory D. JenningsSearch for more papers by this authorWilliam A. Harman, William A. HarmanSearch for more papers by this authorLaura A. Lombardo, Laura A. LombardoSearch for more papers by this authorJean Spooner, Jean SpoonerSearch for more papers by this author Daniel E. Line, Daniel E. LineSearch for more papers by this authorRichard A. McLaughlin, Richard A. McLaughlinSearch for more papers by this authorDeanna L. Osmond, Deanna L. OsmondSearch for more papers by this authorGregory D. Jennings, Gregory D. JenningsSearch for more papers by this authorWilliam A. Harman, William A. HarmanSearch for more papers by this authorLaura A. Lombardo, Laura A. LombardoSearch for more papers by this authorJean Spooner, Jean SpoonerSearch for more papers by this author First published: 15 June 1998 https://doi.org/10.2175/106143098X134514Citations: 10AboutPDF 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 Citing Literature Volume70, Issue41998 Literature ReviewJune 1998Pages 895-912 RelatedInformation DA - 1998/6// PY - 1998/6// DO - 10.2175/106143098X134514 VL - 70 IS - 4 SP - 895-912 SN - 1554-7531 ER - TY - JOUR TI - Nitrogen-15 labeling effectiveness of two tropical legumes AU - Glasener, KM AU - Wagger, MG AU - MacKown, CT AU - Volk, RJ T2 - PLANT AND SOIL DA - 1998/3// PY - 1998/3// DO - 10.1023/A:1004330514833 VL - 200 IS - 2 SP - 149-156 SN - 1573-5036 KW - Desmodium ovalifolium KW - N balance KW - 15N methodology KW - N mineralization KW - Pueraria phaseoloides ER - TY - JOUR TI - Identification of sucrose synthase as an actin-binding protein AU - Winter, H AU - Huber, JL AU - Huber, SC T2 - FEBS LETTERS AB - Several lines of evidence indicate that sucrose synthase (SuSy) binds both G- and F-actin: (i) presence of SuSy in the Triton X-100-insoluble fraction of microsomal membranes (i.e. crude cytoskeleton fraction); (ii) co-immunoprecipitation of actin with anti-SuSy monoclonal antibodies; (iii) association of SuSy with in situ phalloidin-stabilized F-actin filaments; and (iv) direct binding to F-actin, polymerized in vitro. Aldolase, well known to interact with F-actin, interfered with binding of SuSy, suggesting that a common or overlapping binding site may be involved. We postulate that some of the soluble SuSy in the cytosol may be associated with the actin cytoskeleton in vivo. DA - 1998/7/3/ PY - 1998/7/3/ DO - 10.1016/S0014-5793(98)00659-0 VL - 430 IS - 3 SP - 205-208 SN - 1873-3468 KW - actin-binding protein KW - actin cytoskeleton KW - aldolase KW - sucrose synthase KW - phalloidin ER - TY - JOUR TI - Hybrid rank and variance of corn at sites with contrasting humic matter content AU - Van Esbroeck, GA AU - Bowman, DT T2 - CROP SCIENCE AB - Widely adapted, high-yielding genotypes are most easily detected at sites in which differences among hybrids are large and where rankings are similar to the target environment. The objectives of this study were to determine if the relative yields, hybrid variances, and correlations with state-wide means for corn (Zea mays L.) hybrids differed among sites with low and high humic matter (HM) content. Five years of corn yield data from sites with contrasting HM content (0.032 vs. 0.059 g cm−3) located near Plymouth, NC, were collected. An analysis was performed for each year and maturity group which contained 12 to 48 hybrids. Mean yields averaged 12% (0.91 Mg ha−1) less at the high than low HM sites. Hybrid × HM interactions were significant (P < 0.05) in about half of all trials but rarely involved changes in the rank order among hybrids, indicating that duplicating trials on the two soil types was not warranted. Despite lower yields at the high HM sites, ranges and hybrid variances were larger in these sites. Maximum yields were less affected by soil type than minimum yields, indicating greater stress tolerance in high-yielding hybrids. A differential response among hybrids to some additional stress appeared to account for greater hybrid variances observed at the high HM sites. Correlations with state-wide mean performance were greater for high than low HM sites. Locating test sites on soils with high HM content may be an efficient way to detect hybrids capable of producing high yields under a range of soil and climatic conditions. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020011x VL - 38 IS - 2 SP - 347-352 SN - 0011-183X ER - TY - JOUR TI - Cotton response to placement and rate of starter fertilizer AU - Stewart, AM AU - Edmisten, KL T2 - JOURNAL OF PLANT NUTRITION AB - Abstract Application of starter fertilizer at‐planting is a convenient method of applying phosphorus (P) and pre‐plant nitrogen (N) to cotton (Gossypium hirsutum L.). In addition, the placement of starter fertilizer in‐furrow requires no extra tanks or pumps, and can be tank mixed with at‐planting insecticides, fungicides, or plant growth regulators. Over a four‐year period, tests were initiated to determine the effect of 10–34–0 starter fertilizer applied in‐furrow and in a 5 cm to the side and 5 cm below the seed placement (5 cm x 5 cm). Lint yields were measured all four years. Stand counts, Chambers’ skip index, and plant heights were measured the final year. Placement of starter fertilizer in‐furrow was shown to decrease yields compared to a 5 cm x 5 cm placement and a check two out of four years. Plant stands, skip indexes and plant heights were adversely affected by an in‐furrow placement as well. A 5 cm x 5 cm placement did not significantly differ in terms of yield in any year from the check. Plant stands and skip indexes were not affected, but plant height was increased over the check with one rate of starter placed 5 cm x 5 cm. Our results suggest that in‐furrow placement of starter fertilizer has the potential to negatively affect seedling growth and decrease yields. A 5 cm x 5 cm placement of starter fertilizer, while it may not increase yields, does not incur these risks and is a safe, convenient and inexpensive method of applying P or pre‐plant N. DA - 1998/// PY - 1998/// DO - 10.1080/01904169809365457 VL - 21 IS - 5 SP - 967-973 SN - 0190-4167 ER -