Brief Summary of Minutes of Annual Meeting

At the January 15-17, 2004, meeting at the University of California, Davis, there was excellent attendance from the states involved in this group. There was discussion about increasing membership in the group based on areas of expertise and discipline and about involving more states and institutions. Committee members continued discussion of hosting a Seed Biology Conference. Objective 1. Elucidate fundamental mechanisms underlying seed development and germinability. California - The specific goal is to evaluate lettuce populations to identify genetic determinants of seed dormancy and quality. An F7 recombinant inbred line (RIL) population was derived and evaluated for seed quality phenotypes, including germination at elevated temperatures, germination after red and far-red irradiation, and root and hypocotol growth. Using molecular markers (AFLPs, ESTs) mapped in this population, QTL were identified for germination after far-red irradiation, germinated plant quality, seed oil content, and seed weight. Stand establishment of lettuce is hampered in warm regions due to seed dormancy, so genetic analysis of natural variation in dormancy may identify the genes responsible and provide breeders with markers to identify them for developing heat-tolerant varieties. Colorado - This research was designed to understand the factors influencing seed set and production of native species and to develop procedures for increasing seed germination. Saltgrass lines from the front range of Colorado can now be induced to flower during the winter. This should speed the development of turf type cultivars for use in the turf industry. Texas wild rice can now be induced to flower in the greenhouse. Reseach will continue to study seed set with the intention of seed production for use in revegetation and preservation of this endangered species. Delaware - Seed treatments of 'Marglobe' tomato with paclobutrazol (PB), a triazole growth retardant, were examined for seedling growth suppression without having a deleterious effect on germination or emergence. Soaking seeds in the triazole growth retardant Paclobutrazol can be an alternative method of suppressing seedling growth which will have less potential for environmental contamination than the traditional foliar spray or growth medium drench applications. Florida - Germination rate and preliminary work on the priming procedure of selected Bennett and Connick seed lots of lettuce have been evaluated. The experiments indicated peak enzyme activity appears to occur sometime after 48 hours of priming but before any radicle growth has occurred. Additional work is being conducted to correlate endo-beta-mannanase activity with primed lettuce seed prior to germination. Iowa - Research was conducted to investigate the effects of the spiral separator adjustments on removal of soybean splits. Fingers set at 330 degrees resulted in removal of over 90% of the splits with least amount of crop discard. Quality of the finished products was significantly increased. Results from maize seed studies helped assess the extent of natural freeze damage in corn seed lots produced in Iowa in 2003 injured by an early Fall frost. Recommendations about possible seed longevity of affected lots were made based on the knowledge obtained from data collected in the first year of this project which benefitted corn seed companies and producers. Research in Eastern gamagrass helped explain the practical mechanisms of seed dormancy in this species. Producers will benefit from the information to help them maximize the stand potential from Eastern gamagrass plantings. Field studies of flowering and shattering patterns of 'Pete' and 'Iuka' and experiments to evaluate the effects of planting date, planting depth, and stratified and unstratified seed on emergence in Central Iowa have also been completed. Based on two years of data, it would appear that unstratified seed should be used for Fall plantings and stratified seed for Spring plantings. Kentucky - A chromatin immunoprecipitation (ChiP) approach has been successful in identifying DNA fragments bound in vivo by the MADS-domain factor AGL15. Identified a number of genes that were directly regulated by AGL15. Characterized the product of one gene that is involved in catabolism of biologically active gibberellins (Gas); initiated screens to identify interacting proteins. Efforts continue to clone brownseed1 through map based cloning. Mutant screen and characterization of Cold Temperature Germinating (CTG) mutants of Arabidopsis thaliana (Col.) continues. Genes improving the speed with which seeds complete germination at 10 degrees have been identified that will aid in increasing stand establishment success and crop productivity. Work continues to update the database on the world biogeography and class of dormancy for 3580 species; there is information for 7344 species now. Efforts continue to elucidate losses in crop productivity due to sub- or supra-temperatures. Research indicates that the higher moisture concentration of the embryo leads to increased susceptibility to freezing injury and must be considered by seed producers when freezing temperatures are encountered during production. LA - 70S and 80S translational inhibitors were assayed to determine if protein synthesis is required to maintain seed dormancy in red rice. Cycloheximide broke dormancy, while all 70S inhibitors were inactive. A viability test was developed to distinguish between dormant and dead seeds of Spartina alterniflora, a recalcitrant species, and this test was used to determine a moisture content cutoff of 32% seed water content between life and death. Gibberellic acid at the appropriate solution pH will break Spartina dormancy, in contrast to reports in the literature where solution pH was not controlled. MI - From 109 sugarbeet breeding lines and 34 PI's, 12 accessions were identified with high germination capacity in 150 mM NaC1 solution. Selections from these 12 accessions will be used to determine the mode of inheritance of seedling vigor in laboratory conditions as well as saline soils in Egypt. NY-Cornell - Research results indicate that cyclitol galactoside accumulation in soybean seeds increases in response to the supply of free cyclitols that are transported from maternal tissues, targeting the maternal tissues for mechanisms to enhance health-related cyclitols in seeds. NY-Cornell-Geneva - Field studies were conducted on two seed lots of Hystyle and Hercules beet seeds treated with and without Yield Shield. Yield, grade and economic return were calculated from replicated field plots. Yield Shield increased yield and gross return per acre, especially in Hystyle, while Hercules only showed a slight improvement in yield. Two methods were tested to enhance table beet seed germination: brush-soak and priming. The brush-soak technique was developed to remove the corky outer covering of the beet seed that contains mucilage and phenolic chemical inhibitors. Brushing was observed under the microscope to remove the outer soft spongy mucilage, compared to the nontreated seeds. Priming was intermediate with the removal of some of the soft mucilage. The seed treatment, Thiamethoxam (Cruiser), was effective in controlling Potato leafhopper past bloom, and yields were comparable to conventional foliar insecticide spray treatments on snap beans. Ohio - An image processing computer application to automatically assess the vigor of three-day soybean seedlings was developed. The development of a method to utilize computers to evaluate seedling length determinations provides a superior seed vigor test compared to existing vigor tests, and enhances test standardization from laboratory to laboratory. Oregon - The Arabidopsis enhancer-trap population from the Arabidopsis Biological Resource Center (ABRC) at Ohio State University was screened for seed-expressed genes. Out of the 1,130 pools of 10 lines examined, 147 pools showed GUS expression in seeds. Isolation and characterization of genes in the positive enhancer-trap lines will identify seed-germination associated genes in Arabidopsis and other species. Objective 2. Development methods for improving seeds as genetic delivery systems. California - Studies were conducted with four lettuce cultivars exhibiting differing responses to priming and post-priming treatments. Overall, slow drying or moisture content reduction treatments tended to extend longevity and increase vigor relative to seeds rapidly dried after priming. Emission of volatiles from heated seeds increased with seed moisture content, but was not well correlated with seed longevity. Methods to prevent the reduction in storage life that often accompanies seed priming would be valuable in the broader application of this enhancement technique. Iowa - Fifteen new seed health methods were standardized for the National Seed Health System in 2003 and published at the NSHS website www.seedhealth.org. The availability of new seed health methods will provide the opportunity for more national organizations to become accredited in the NSHS. The first of a series of phytosanitary resolution workshops was held in Thailand. The workshops in South-East Asia will lead to elimination of phytosanitary regulations on seeds that are scientifically unjustified and thus facilitate seed trading between that region and the US. Research on the soybean seed discoloration has indicated that control of the overwintering and first generations of the bean leaf beetle could be an effective means of reducing the problem. Field surveys in growers' fields will determine whether the strategy of controlling bean leaf generations with insecticides to minimize soybean seed discoloration will be efficacious and cost effective for Iowa soybean producers. Oregon - Development of the rudimentary embryo in mature carrot seed during imbibition was characterized. The expression of endo-B-mannanase, which is thought to be involved in endosperm degradation, was characterized. The mannanase gene can be used as a marker to monitor embryo development in Umbeliferae seeds during priming. South Dakota - Developing methods to measure physical forces that are believed to contribute to damage during drying or storage of seeds. Using the hydration forces formalism and water sorption isotherms of phosphatidylcholines and sugar mixtures, we were able to show independent hydration of the polar lipid and sugar components, which suggests exclusion of the sugars from the immediate surface of the lipid. Developed a new method to approximate molecular mobility within desiccated seeds using models for relaxation of glasses that are based on configuration entropy and heat capacity measurements. Using the two newly developed biophysical techniques, future studies will compare intramolecular distances and mobility with seed desiccation tolerance and longevity among phylogenetically diverse species. Texas - Evaluated solid matrix priming (SMP) in combination with hydrogen peroxide and fungicides to improve seed germination and vigor of triploid (3x) 'Tri-X-313' watermelon. Efficient seed enhancement treatments, such as solid matrix priming, in combination with fungicides, have the potential to increase germination and seedling uniformity of triploid watermelon genotypes. These treatments may also provide an improvement in the overall transplant quality and field performance under stress conditions. Virginia - Bedding plant height is controlled by reducing growing temperatures or by using synthetic chemical regulators such as paclobutrazol and other triazoles. There is strong demand for a natural organic growth regulator that could be applied as a seed treatment or two small seedlings to control plant height without causing negative health and environmental impact. Trehalose, a natural sugar from plants and fungi, has been identified as a candidate molecule that provides natural growth inhibition when applied to germinated seedlings in micromolar concentrations. Trehalose and other natural metabolites can be used to create natural, certified organic commercial seed treatments for controlling the height of bedding plants. Arabidopsis thaliana has been utilized to obtain information about the functional roles of the two glutathione reductase GR genes in seed development, storage and germination. Glutathione may be involved in determining the longevity of Arabidopsis seed storage.

Aberle, E.Z., L.R. Gibson, A.D. Knapp, P.M. Dixon, K.J. Moore, E.C. Brurnmer, and R. Hintz. 2003. Optimum planting procedures for eastern gamagrass. Agron. J. 95:1054-1062. Adam, K. and M. Misra. 2003. Effect of spiral separator adjustments on removal of soybean splits. American Society of Agricultural Engineers midcentral meeting, paper #MC03-101. Adam, K., M. Misra, and D. Thoreson. 2003. Removal of Ergot from barley by density separation, Applied Engineering in Agriculture, Vol. 20(1):39-43. Argyris, J., D. VanSanford and D. TeKrony. 2003. Fusarium graminearum infection during wheat seed development and its effect on seed quality. Crop Science 43:1-7. Bicanic D., Persijn S., Taylor A., Cozijnsen J., van Veldhuyzen G. Lenssen G. and Wegh H. 2003. Quality assessment of cabbage (Brassica olearacea) seeds by the CO laser photo acoustic and FTIR detection of ethylene and acetaldehyde. Review of Scientific Instruments 74,689-693. Bradford, K.J., Downie, A.B., Gee, O.H., Alvarado, V.Y., Yang, H., Dahal, P. 2003. Abscisic acid and gibberellin differentially regulate expression of genes of the SNF1-related kinase complex in tomato seeds. Plant Physiol. 132: 1560-1576. Cantliffe, D.J. 2003. Seed Enhancements. Acta Horticulturae. 607:53-62. De los Reyes, B.G., McGrath, J.M. 2003. Cultivar-specific seedling vigor and expression of a putative oxalate oxidase germin-like protein in sugar beet (Beta vulgaris L.). Theor. Appl. Genet. 107:54-61. De los Reyes, B.G., Morsy, M., Gibbons, J., Varma, T.S.N., Antoine, W., McGrath, J.M., R. Halgren, R., and M. Redus, M. 2003. A snapshot of the low temperature stress transcriptome of developing rice seedlings (Oryza sativa L.) via ESTs from subtracted cDNA library. Theor. Appl. Genet. 107:1071-1082. De los Reyes, B.G., Myers, S.J., McGrath, J.M. 2003. Differential stress-induction of glyoxylate cycle enzymes as a marker for seedling vigor in sugar beet (Beta vulgaris). Mol. Gen. Genomics 269:692-698. Downie, B., Zhang, D., Dirk, L.M.A., Thacker, R.R., Pfeiffer, J., Drake, J., Levy, A., Butterfield, D.A., Buxton, J.W., Snyder, J.C. 2003. Communication between the maternal testa and the embryo and/or endosperm affect testa attributes in tomato. Plant Physiology 133:145-160. Downie B, Gurusinghe S, Dahal P, Thacker RR, Snyder JC, Nonogaki H, Yim K, Fukanaga K, Alvarado V, Bradford KJ. 2003. Expression of a GALACTINOL SYNTHASE gene in tomato seeds is upregulated prior to maturation desiccation and again following imbibition whenever radicle protrusion is prevented. Plant Physiology 131 (3), 1347-1359. Geneve,R.L. 2003. Impact of temperature on seed dormancy. HortScience 38:336-341. Geneve, R.L. 2003. Plant Propagation, in Agricultural Sciences, R. Lal (ed). Encyclopedia of Life Support Systems, Developed under the auspices of the UNESCO, Eolss Pub., Oxford UK, [http:www.eolss.net. Geneve,R.L., K.W. Pomper, S.T. Kester, J.N. Egilla, C.L.H. Finneseth, S. Crabtree, and D.R. Layne. 2003. Propagation of Pawpaw -a Review. HortTechnology 13:428-433. Gomes, C.I. and R.L. Obendorf. 2003. Transport of myo-inositol, D-pinitol, and D-chiro- inositol in soybean explants (abs.). ASA-CSSA-SSSA Annual Meeting Abstracts CD 2003, (AOO-gomes301672-oral.pdf). Grange, S., D.I. Leskovar, L.M. Pike, and B.G. Cobb. 2003. Seed coat structure and oxygen-enhanced environments to improve germination of triploid watermelon. J. Amer. Soc. Hort. Science 128:253-259. Hoffmaster, A.L., K. Fujimura, M. B. McDonald, and M.A. Bennett. 2003. An automated system for vigor testing three-day-old soybean seedlings. Seed Sci. & Technol. 31:701-713. Homrichhausen, T.M., Hewitt, J.R., Nonogaki, H. 2003. Endo-B-mannanase activity is associated with embryo development in germinating carrot (Daucus carota L.) Seeds. Seed Science Research 13:219-227. Jyoti, J.L., A.M. Shelton, and A.G. Taylor. 2003. Film-coating seeds with chlorpyrifos for germination and control of cabbage maggot (Diptera: Anthomyiidae) on cabbage transplants J. Entomol. Sci. 38(4):553-565. Koning, G., D.M. TeKrony and S.A. Ghabrial. 2003. Soybean seedcoat mottling: Association with Soybean mosaic virus and Phomopsis spp. seed infection. Plant Disease 87:413-417. Kozareva, I., D.J. Cantliffe, and R.T. Nagata. 2003. Effect of seed maturation temperature on ethylene production, sensitivity to ethylene and lettuce seed germination. HortScience. Vol. 38(5):772. Kozareva, I., D.J. Cantliffe, R.T. Nagata, and H.J. Klee. 2003. New support for the involvement of ethylene in lettuce germination at supraoptimal temperature. Acta Horticulturae. In press. Lemke, B.M., L.R. Gibson, A.D. Knapp, P. M. Dixon, K.J. Moore, and R. Hintz. 2003. Maximizing seed production in eastern gamagrass. Crop Sci. 95:863-869. McDonald, M.B. 2003. Seed research in the United States -and its future. Seed Technol. 25:78-83. McGrath, J.M. 2003. Registration of SR96 and SR97 smooth-root sugarbeet germplasm with high sucrose. Crop Sci. 43:2314-2315. McDonald, M.B., K. Fujimura, Y. Sako, A.F. Evans, and M.A. Bennett. 2003. Computer imaging to improve seed quality determinations. pp. 15-28. In: Digital Imaging and Spectral Techniques: Applications to Precision Agriculture and Crop Physiology (eds. T. VanToai, D. Major, M. McDonald, J. Schepers, and L. Tarpley), ASA Spec. Publ. No. 66, Madison, WI. Michelmore, M., Knapp, S., Rieseberg L., Kesseli, R., Bradford, K., Jackson, L. 2003. Comparative genomics of domestication traits in lettuce and sunflower. Plant and Animal Genome Conference, San Diego, CA, January 11-15. Nicolis, G., Bradford, K.J., Come, D., and Pritchard, H.W., eds. 2003. The Biology of Seeds: Recent Research Advances, CAB International, Wallingford, U.K. Nonogaki, H. and Bradford, K.J. 2003. Tissue printing for localization of mRNA expression in seeds. In: G. Nicolas, K.J. Bradford, D. Come, and H.W. Pritchard, eds., The Biology of Seeds: Recent Research Advances, CABI Publishers, Wallingford, UK, pp. 171-179. Obendorf, R.L., S. Odorcic and C.I. Gomes. 2003. Enhancing health-related cyclitols in soy products (abs.). qth International Symposium on the Role of Soy in Preventing and Treating Chronic Disease, AOCS, Orlando, FL (September 21-24, 2003) 5:44-45. Obendorf, R.L. and S. Odorcic, S. 2003. Recent accomplishments and new opportunities in seed research. pp 447-452 in Nicolas, G., K.J. Bradford, D. Come, and H. Pritchard (Eds.) The Biology of Seeds: Recent Research Advances. Wallingford, UK, CABI Publishing, ISBN 085199653. Obendorf, R.L. 2003. Structure of galactosyl cyclitols in buckwheat and soybean seeds (abs.). ASA-CSSA-SSSA Annual Meeting Abstracts CD 2003, (C04-obendorf215566- oral.pdf). Obendorf, R.L. 2003. Structures of galactosyl cyclitols in seeds (abs.). The 4th International Workshop on Desiccation Tolerance and Sensitivity of Seeds and Vegetative Plant Tissues, Nieuwoudville, Northern Cape Province, South Africa (24-30 August 2003) 4:23. Odorcic, S. and R.L. Obendorf. 2003. Galactosyl cyclitol accumulation enhanced by substrate feeding of soybean embryos. pp 51-60 in Nicolas, G., K.J. Bradford, D. Come, and H. Pritchard (Eds.). The Biology of Seeds: Recent Research Advances. Wallingford, UK, CABI Publishing. ISBN 0 85199 653 1. Odorcic, S., R.L. Obendorf, T. Ueda, M.P. Coseo, and E. Vassallo. 2003. Fagopyritol B1 biosynthesized by galactinol synthase in soybean seeds (abs.). ASA-CSSA-SSSA Annual Meeting Abstracts CD 2003, (C04-odorcic198855-oral.pdf). Odorcic, S., T. Peterbauer, A. Richter and R.L. Obendorf. 2003. Probing the pea seed: The search for an alpha-galactosidase gene (abs.). ASA-CSSA-SSSA Annual Meeting Abstracts CD 2003, (AOO-odorcic729225-oral.pdf). Saunders, J.W., Halloin, J.M., McGrath, J.M. 2003. Registration of EL52 and EL48 sugarbeet germplasm releases. Crop Sci. 43:744-745. Siriwitayawan, G., Downie, A.B., Geneve, R.L. 2003. Ethylene evolution is positively correlated with seed vigor in sweet corn and tomato seed lots with differing vigor levels but similar germination capacity. Journal of the American Society for Horticultural Science. 128:608-614. Siriwitayawan, G., Dull, M., Kester, S., Downie, B., Geneve, R. 2003. Ageing in tomato reduces the capacity of seeds to produce ethylene, while priming increases ethylene evolution during germination. In: G. Nicolas, K.J. Bradford, D. Come and H.W. Pritchard, eds, The Biology of Seeds: Recent Research Advances CAB International: Wallingford, U.K. pp. 441-446. Siriwitayawan, G., Geneve, R.L. and Downie, A.B. 2003. Seed germination in ethylene insensitive mutants from tomato and arabidopsis. Seed Science Research 13:303-314. Still, J.R. and W.G. Pill. 2003. Germination, emergence, and seedling growth of tomato and impatiens in response to seed treatments with Paclobutrazol. HortScience 38:1201-1204. Taylor, A.G. 2003. Seed quality. In: Thomas, B., D.J. Murphy and B.G. Murray. Encyclopedia of Applied Plant Sciences. Elsevier Acad. Press. p. 1284-1291. Taylor, A.G. 2003. Seed Treatments. In: Thomas, B., D.J. Murphy and B.G. Murray. Encyclopedia of Applied Plant Sciences. Elsevier Acad. Press. p. 1291-1298. Taylor, A.G., M.C. Goffinet, S.A. Pikuz, T.A. Shelkovenko, M.D. Mitchell, K.M. Chandler and D.A. Hammer. 2003. Physico-chemical factors influence beet (Beta vulgaris L) seed germination. In: G. Nicolas, K.J. Bradford, D. Come and H.W. Pritchard. The Biology of Seeds: Recent Research Advances. CABI. p. 433-440. TeKrony, D.M. 2003. REVIEW: Precision is an essential component of seed vigour testing. Seed Science and Technology 31: 435-447. Tian, X., A.D. Knapp, L.R. Gibson, R. Struthers, K.J. Moore, E.C. Brummer and T.B. Bailey. 2003. Response of eastern gamagrass seed to gibberellic acid buffered below its pKa. Crop Sci. 43:927-933. Truco, M.J., Ochoa, 0., Pandel, B., Lavelle, D., McHale, L., Argyris, J., van Wijk, R., Peleman, J., Bradford, K. and Michelmore, R. 2003. QTL analysis of agriculturally important traits using a recombinant inbred line population from cultivated lettuce and its wild progenitor L. serriola. Plant and Animal Genome Conference, San Diego, CA, January 11-15. Watkinson, J.O. and G.E. Welbaum. 2003. Characterization of gene expression in roots of Cypripedium parviflorum var. pubescens incubated with a mycorrhizal fungus. Acta Horticulturae 624:463-470. Whitmer, X., Nonogaki, H., Beers, E.P., Bradford, K.J., Welbaum, G.E. 2003. Characterization of chitinase activity and gene expression in muskmelon seeds. Seed Sci. Res. 13:167-178. Wu, C.T., and Bradford, K.J. 2003. Class I chitinase and B-1,3-glucanase are differentially regulated by wounding, methyl jasmonate, ethylene and gibberellin in tomato seeds and leaves. Plant Physiol. 133:263-273. Zhao, T.-Y., Meeley, R.B., Downie, B. 2003. Aberrant processing of a Maize GALACTINOL SYNTHASE transcript is caused by heat stress. Plant Science 165: 245-256.