Annual/Termination Reports:

[12/31/2003] [02/24/2005] [02/01/2006] [01/03/2007] [10/31/2007]

Report Information

Participants

Kent Bradford (University of California);
Daniel Cantliffe (University of Florida);
Marc Cohn (Louisiana State University);
Allen Knapp (Iowa State University);
Alan Taylor (Cornell University-Geneva);
Ralph Obendorf (Cornell University-Ithaca);
Bruce Downie (University of Kentucky);
Miller McDonald (Ohio State University);
Hiro Nonogaki (Oregon State University);
Mitch McGrath (USDA-ARS, East Lansing, MI);
Paul Beuselinck (USDA-ARS, Columbia, MO);
Daniel Leskovar (Texas A&M University)

Brief Summary of Minutes

Accomplishments

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.<br /> <br /> Committee members continued discussion of hosting a Seed Biology Conference.<br /> <br /> Objective 1. Elucidate fundamental mechanisms underlying seed development and germinability. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> Objective 2. Development methods for improving seeds as genetic delivery systems. <br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> 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. <br /> <br /> 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. <br /> <br /> <br /> <br /> <br /> <br />

Publications

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.<br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> Cantliffe, D.J. 2003. Seed Enhancements. Acta Horticulturae. 607:53-62.<br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> Geneve,R.L. 2003. Impact of temperature on seed dormancy. HortScience 38:336-341. <br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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). <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> Koning, G., D.M. TeKrony and S.A. Ghabrial. 2003. Soybean seedcoat <br /> mottling: Association with Soybean mosaic virus and Phomopsis spp. seed infection. Plant Disease 87:413-417. <br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br /> McDonald, M.B. 2003. Seed research in the United States -and its future. Seed Technol. 25:78-83. <br /> <br /> McGrath, J.M. 2003. Registration of SR96 and SR97 smooth-root sugarbeet germplasm with high sucrose. Crop Sci. 43:2314-2315. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> Obendorf, R.L. and S. Odorcic, S. 2003. Recent accomplishments and new <br /> 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. <br /> <br /> 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). <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> Odorcic, S., R.L. Obendorf, T. Ueda, M.P. Coseo, and E. Vassallo. 2003.<br /> Fagopyritol B1 biosynthesized by galactinol synthase in soybean seeds (abs.). ASA-CSSA-SSSA Annual Meeting Abstracts CD 2003, (C04-odorcic198855-oral.pdf). <br /> <br /> 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). <br /> <br /> Saunders, J.W., Halloin, J.M., McGrath, J.M. 2003. Registration of EL52 and EL48 sugarbeet germplasm releases. Crop Sci. 43:744-745. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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. <br /> <br /> TeKrony, D.M. 2003. REVIEW: Precision is an essential component of seed vigour testing. Seed Science and Technology 31: 435-447. <br /> <br /> 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. <br /> <br /> 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. <br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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.<br /> <br /> 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. <br /> <br />

Impact Statements

1. Identification of genes responsible for dormancy, germination, and stress tolerance will provide breeders with important genetic markers.
2. Efficient seed enhancement treatments and growth regulation treatments will provide improved field performance for producers with the potential of less environmental damage.
3. Fifteen new seed health methods were standardized for the National Seed Health System (NSHS) which will provide the opportunity for more national organizations to become accredited.
4. Research on insecticides will aid in quality and product yield.
5. Use of computer applications provides superior seed vigor tests and enhanced test standardization for laboratories.
6. Research on seed production will be useful for revegetation and preservation of endangered native plant species.

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Report Information

Participants

Phil Allan, Brigham Young University;
Kent Bradford, kjbradford@ucdavis.edu, University of California;
Bruce Downie, adownie@uky.edu, University of Kentucky;
Harrison Hughes, Harrison.Hughes@ColoState.edu, Colorado State University;
Allen Knapp, adknapp@iastate.edu, Iowa State University;
Karen Koster, kkoster@usd.edu, University of South Dakota;
Daniel Leskovar, d-leskovar@tamu.edu, Texas A&M University;
Miller McDonald, mcdonald.2@osu.edu, Ohio State University;
Mitch McGrath, mitchmcg@msu.edu, USDA-ARS, East Lansing, MI;
Hiro Nonogaki, hiro.nonogaki@oregonstate.edu, Oregon State University;
Ralph Obendorf, rl01@cornell.edu, Cornell University-Ithaca;
Paul Rasmussen, paul@agx.usu.edu, Utah State University

Brief Summary of Minutes

Accomplishments

At the annual meeting held in Colorado State University, the attendance was excellent from the majority of the states involved. <br /> <br /> There was ongoing discussion about recruiting new members; additional state and industry individuals will be invited to participate. Participation of stakeholders in this group is important because they apply the research and report on results. <br /> <br /> There was continued discussion about sponsoring a symposium as a way to increase visability among seed science practitioners and funding agencies. It would also help create collaborations among scientists in the public, private and international communities. <br /> <br /> 1. Controlled environment studies during seed development on seed quality: <br /> <br /> California - Studies were initiated to focus on developing post-priming protocols that will enhance the longevity of primed seeds and on identifying the mechanisms involved in the post priming effects. <br /> <br /> Delaware - Determined that the most rapid seed treatment to establish beet and chard microgreens was to germinate seeds in moist vermiculite, then sow this mixture. Other research determined reasons for enhanced germination responses in microgreens. Microgreens are increasing in popularity; this research has developed a way to increase the speed of crop establishment.<br /> <br /> Florida - Application of the ethylene action inhibitor, silver thiosulfate (STS) reduced germination of the thermotolerant lettuce genotype 'Everglades' (EVE) at supraoptimal temperature and germination of the thermosensitive enotype 'Dark Green Boston' (DGB) at optimal and supraoptimal temperatures. The abscission initiating compound, 5 chloro-e-methyl-4-nitro-1H-pyrazole (CMN-P) inhibited EVE germination in a smilar concentration- and temperature-dependent manner to that of STS. However, the mechanism is unclear. <br /> <br /> Additional germination studies suggest that the ability of lettuce seeds to germinate at supraoptimal temperature is related to their ability to maintain and increase their ethylene production at supraoptimal temperature.<br /> <br /> In transfenic lettuce studies, the experiments conducted with T2 adn T3 EVE ETR seeds demonstrate that the ability of lettuce seeds to germinate, especially under stressful conditions, is determined by the balance between ethylene perception and ethylene production and increase in ethylene production can compensate for decreased perception. Studies with DGB and EVE ACC plants demonstrated that if lettuce seeds had normal (WT) ethylene perception, their germination at supraoptimal temperature, was solely determined by the amount of ethylene produced. <br /> <br /> Extended emergence periods can predispose plants to damage by adverse environmental conditions and can cause low uniformity and a low percentage of seedling emergency. The current work determined optimal hydrothermal timing for priming in lettuce seeds, independent of cultivar, seed lot and storage using a low cost endo-beta-mannanase (EBM) gel assay. Experiments demonstrate that the occurrence of EBM activity in a particular seed lot equated well with the ability of that lot to germinate at high temperatures after priming, dry-back and subsequent storage. The EBM test is simple, rapid and inexpensive to run. Using the EBM test as an additional insight to achieving optimal hydrothermal time during priming would give additional safe guards and quality control for companies which either prime or who sell primed lettuce seed.<br /> <br /> Iowa - Two sunflower varieties were produced in 1999 and 2000 by Cargill Hybrid Seeds. Viability was determined. Geotype, storage temperature, duration and germination methodologies were important variables in the assessment of seed lots. Completed first round of experiments which investigated low temperature stresses without a specific acclimation treatment, stresses following acclimation, and the ability to recover. <br /> <br /> Kentucky - Successfully developed an automated data capture system for small seeded species using machine vision. This research utilizes an automated system to measure germination and growth rates. Continues to update their database on the world biogeography of seed dormancy classes. The 1998 book on Seeds contains information on the biogeography and class of dormancy for 3580 species; they now have information for 7344 species. <br /> <br /> Kentucky also examined changes on freezing point temperature in seed, embryo and endosperm tissue in maize. The primary conclusion is 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. A study concerning the relationship between air temperature during seed filling and seed germination and vigor in soybean was conducted. Findings support results of experiments that high temperature during seed infection or physical injury reduce soybean seed germination and vigor. <br /> <br /> Michigan - All archived germplasm through 1992 has been field tested, and two broad-based genetic populations have been developed from promising materials. The sugarbeet research harvester was completed with the first ever real-time sucrose analysis capability using near-infrared instrumentation. This instrument also measured moisture content, and provides the first opportunity for breeders to select on the basis of moisture content.<br /> <br /> Ohio- Research was conducted to determine how water availability of the mother plant affects seed germinability in lettuce. The results indicated that water availability during seed development not only affected seed yield and individual weight, but also seed germinability under sub-optimal conditions. The Saturated Salt Accelereated Aging (SSAA) test and the Seed Vigor Imaging System (SVIS) are practical and accurate determinants of lettuce seed quality and distinquishes between high and poor quality lettuce seed lots.<br /> <br /> An image processing computer application was developed to collect statistics from seeds. The method presented requires an inexpensive scanner and a modern personal computer. The seed identification system is designed to be rapidly adapted to specific seed types and trained without knowledge of artificial intelligence. <br /> <br /> Oregon - Research on the tomato endo-B-mannanase, which is involved in cell wall disassembly and weakening of seed endosperm, led to the discoverey of a novel endo-B-mannanase gene (termed LeMAN5) in the tomato genome by genome-walking PCR and BAC library screening. <br /> <br /> South Dakota - Methods used to store plant genetic resources depend upon the ability of seeds to survive dehydration and freezing. Preliminary analysis of the seed hydration data suggests that differences in the hydration forces parameters may correlate with desiccation tolerance and longevity; however, more data are required to determine whether this correlation truly relates to longevity or whether it merely reflects seed composition. The hydration data acquired for biomolecules may help us to elucidate the contribution of seed composition to the overall hydration force parameters of the seed.<br /> <br /> Texas - Evaluated solid matrix priming (SMP) in combination with hydrogen peroxide or the fungicide Captan to improve rate and germination percentage of at high or low (optimal) medium moisture. The most significant response for SMP treatments was the improvement in the germination rate for diploid cultivars at both moisture levels, and for triploid cultivars at optimal medium moisture. <br /> <br /> Shoot and root growth were evaluated in response to exogenous ABA in pepper poblano 'Tiburon' seedlings during transplant maturity (pre-transplant). The hypothesis was that ABA would induce stress tolerance while maintaining stem growth control up to 8 days after treatment (dat). Drench application to roots was more effective than foliar treatments. Field survival upon transplanting was not affected by ABA foliar or drench. This is a positive response, indicating that ABA early growth control is reversible. <br /> <br /> Efficient pepper seed enhancement treatments such as solid matrix priming and pre-transplant conditioning treatments to improve seedling stress tolerance have the potential to increase germination and performance under unfavorable field conditions. <br /> <br /> 2. Develop methods to quantify free radicals and antioxidants. Identify QTL associated with seed quality traits in selected crop plants:<br /> <br /> California - Lettuce populations are being evaluated to identify genetic determinants (QTL) of seed dormancy and quality. Lettuce crop establishment is hampered in warm regions due to seed dormancy, so development of cultivars with the capacity to terminate at high temperatures would have commerical applications.<br /> <br /> Iowa - The U.S. annually exports more than $750 million in seed. Income from international sales of maize seeds total $168 million. Most of the hybrid maize seed is produced in the Midwestern states, where early-Fall killing frosts are not uncommon. Immature maize seed can suffer severe mechanical and biochemical damage due to freezing of the intra- and extra-cellular water. Research was conducted on maize genes after freeze injury. Results from these studies helped assess the natural damage in corn seed lots due to an early Fall frost in 2003. Recommendations to the affected seed companies were made based on the knowledge collected in the first year of this project.<br /> <br /> Kentucky - Identifying DNA fragments bound in vivo by the MADS-domain factors AGL15. Identified a number of genes directly regulated by AGL15 and further characterized the product of one gene that is involved in catabolism of biologically active gibberellins (Gas). Current work focuses on identification of proteins that interact with AGL15 to control gene expression and high-throughput mapping of AGL15 binding sites using a custom ChIP-chip approach. <br /> The Downie Lab continues to walk to brownseed1. 15 BAC clones hybridizing to the RFLP marker CT151, tightly linked to bs1, have been recovered.<br /> <br /> The Downie Lab has identified 2 of 3 cold temperature germinating-dominant (ctg-D) mutants, recovered from screens of Arabidopsis activation tagged lines and capable of completing germination at 10 degree C. faster than wild type.<br /> <br /> Louisiana - Research was conducted to determine if translational activity (protein synthesis) is required to maintain seeds in the dormant seeds. A chemical genetics approach was initially taken to determine if protein synthesis inhibitors break dormancy of red rice caryposes (naked seeds). It is tentatively concluded from the overall data set that new protein synthesis is not required to maintain seed dormancy in red rice, but rather the controlling proteins are synthesized during grain development and are stabilized in the seed after it is shed from the mother plant. The results enhance our understanding of the physiological factors that control whether weed or native plant seeds germinate or remain dormant in the soil. Identification of new physiological factors increases the range of seed components that can serve as targets for the design of new, environmentally benign, weed control treatments, or modification of cultural practices. <br /> <br /> Michigan - The genetic basis of traits in sugarbeets is being met through the generation of Recombinant Inbred Lines (RILs). The furthest developed of these have been developed over the last six years. Currently, over 3,000 of the proposed 5,000 RILs have been advanced to the F3 generation or greater. Molecular marker development has proceeded reasonably well, with a new technique developed in this program coined EST-UTR showing greatest promise as a tool for EST-anchored PCR markers. Germplasm representing 34 wild PI's and 109 ARS germplasms were used to develop a new seedling vigor measure. Two new seedling disease resistance assays were developed. Both allow analyses of acquisition of seedling disease tolerance as well as allow for direct screening for seedling resistance in breeding populations.<br /> <br /> NY-Cornell - Fagopyritols are galactosyl cyclitols in buckwheat seeds with similarities to a putative insulin mediator deficient in non-insulin dependent diabetes mellitus and polycystic ovary syndrome. Results of this research demonstrated that multifunctional GolS homologues in buckwheat seeds confer fagopyritol synthase activities and that the specificity for fagopyritol A1 synthesis may be mediated by a unique class of GolS homologues. The identification of a cDNA representing MRNA encoding an enzyme protein that catalyzes the formation of fagopyritol A1 provides new opportunities to use this plant enzyme to form a unique bond in the synthesis an insulin mediator and adds to our understanding of the potential for the use of buckwheat products in the treatments of type II diabetes. <br /> <br /> Ohio - Dof proteins are a family of transcription factors found only in plants. Several Dof genes have been characterized to control a variety of seed-specific functions from seed maturation to germination and dormancy. <br /> <br /> Oregon - To identify seed germination-associated genes, Oregon has utilized Arabidopsis enhancer-trap lines. Arabidopsis B-glucuronidase (GUS) enhancer-trap lines have been created and successfully used to identify tissue-specific gene expression in many plant organs. A library has been constructed of Seed-GUS-Expression lines and individual lines are being characterized. Using this approach, GATA zinc finger protein has been identified that plays a critical role in breaking dormancy during cold stratification of Arabidopsis seeds. Characterization of other transcription factors identified from the enhancer trap lines is ongoing. <br /> <br /> Discovery of the anther/pollen endo-B-mannanase contributes to the general understanding of the biological functions of endo-B-mannanase which is one of the major players in tomato seed germination. Furthermore, the characterization of this anther/pollen mannanase has revealed a very strong and useful promoter for gene expression in anther and pollen, which could be useful for pollination control in seed production. <br /> <br /> 3. Adapt seed coating equipment for seed treatment application: <br /> <br /> A mechanical planter was developed for large seeds (i.e., lima bean) in small plots that is easy to use and move, and is inexpensive. The development of the precision mechanical planter for large seeds should assist researchers their planting of small plots.<br /> <br /> An experiment was conducted to determine the effectiveness and efficiency of color sorting in removing adventitious purple corn from yellow corn. The efficiency of the color-sorting machine averaged 97.21% to 99.18%.<br /> <br /> Plans for the upcoming year include post-priming protocols of primed seeds, enhanced germination responses and seed vigor, temperature and air and water stress tolerance. Work will also continue to use QTL analysis to determine gene expression for seed dormancy and quality.<br /> <br />

Publications

Argyris, J., D. TeKrony, D. Hershman, D. Van Sanford, M. Hall, B. Kennedy, M. Rucker and C. Edge. 2004. Fusarium head blight severity in the greenhouse compared to movement of Fusarium graminearum in inoculated wheat. Crop Sci. (in press).<br /> <br /> Argyris, J.M., Truco, M., Ochoa, O., Still, D., Knapp, S.J, Michelmore, R.W., and Bradford K.J. 2004. QTL Analysis of seed dormancy in lettuce. 3rd International Symposium on Plant Dormancy: From Molecular Level to Whole Plant, Wageningen University, The Netherlands, May 25-28.<br /> <br /> Birmingham, A.M., E.A. Buzby, D.L. Davis, E.R.Bensen, W.G. Pill, T.A. Evans, R.P. Mulrooney, and M.W. Olszewski. 2004. Precision seeder for large seeds in small plots. HortTechnology 14:1-3.<br /> <br /> Bonina, J. and D. J. Cantliffe. 2004. Seed production and seed sources of organic vegetables. HS 981. 2004. EDIS http://edis.ifas.ufl.edu. <br /> <br /> Bradford, K.J., and Still, D.W. 2004. Applications of Hydrotime Analysis in Seed Testing. Seed Technology 26:75-85. <br /> <br /> Bryant, G. and K.L. Koster, 2004. Dehydration of solute-lipid systems: hydration forces analysis. Colloids and Surfaces B: Biointerfaces 35: 73-79.<br /> <br /> Cohn, M.A. 2004. Physiology of dormancy-breaking mechanisms in red rice (invited symposium talk). Abstract S22MT20BP01, 4th International Weed Science Congress, Durban, South Africa. p. 75.<br /> <br /> Downie, B., Dirk, L.M.A., Xu, Q., Drake, J., Zhang, D., Dutt, M., Levy, A., Butterfield, D.A., Geneve, R.L., Corum III, J.W., Lindstrom, K.G., Snyder, J.C. 2004. A physical, enzymatic, and genetic characterization of perturbations in the brownseed mutants of tomato. Journal of Experimental Botany 55: 961-973.<br /> <br /> Dutt, M. and R.L. Geneve. 2004. Elevated levels of ethylene during germination reduces the time to radicle emergence in impatiens. Acta Horticulturae 631:43-47. <br /> <br /> Egli, D.B., D.M. TeKrony J.J. Heitholt, and J. Rupe. 2004. Relationship between air temperature during seed filling and seed germination and vigor in soybean. Crop Sci. (In Press).<br /> <br /> Egli, D.B., D.M. TeKrony, and J.F. Spears. 2004. High temperature stress and soybean seed quality: Stage of seed development. Seed Tech. (in press).<br /> <br /> Egli, D.B., and W.P. Bruening, 2004. Water stress, photosynthesis, seed sucrose levels and seed growth in soybean. J. Agr. Sci. 142: 1-8. <br /> <br /> Filichkin, S.A., Leonard, J.M., Monteros, A., Liu, P.-P., Nonogaki, H. 2004. A novel endo-_-mannanase gene in tomato LeMAN5 is associated with anther and pollen development. Plant Physiology 134:1080-1087. <br /> <br /> Geneve, R.L. 2004. Vigor testing in flower seeds. In: M.B. McDonald and F. Kwong (eds.). Flower Seeds, Biology and Technology. CAB International, London. pp. 311-332. <br /> <br /> Guretzky, J.A. K.J. Moore, A.D. Knapp, and E.C. Brummer. 2004. Emergence and survival of legumes seeded into pastures varying in landscape position. Crop Sci. 44:227-233.<br /> <br /> Hewitt, J.R., Liu, P.-P., Nonogaki, H. 2004. Physiological roles of the endosperm in Arabidopsis seed germination. 29th West Coast Biological Sciences Undergraduate Research Conference, San Diego, CA.<br /> <br /> Hewitt, J.R., Liu, P.-P., Nonogaki, H. 2004. Testa and endosperm rupture in germinating Arabidopsis seeds. The American Society of Plant Biologists Annual Meeting, Orlando, FL.<br /> <br /> Hoffmaster, A. L., K. Fujimura, M. B. McDonald, and M. A. Bennett. 2004. An automated system for vigor testing three-day-old soybean seedlings. Intern. Seed Test. Assoc.<br /> <br /> Homrichhausen, T.M., Liu, P.-P., Nonogaki, H. 2004. Screening of Arabidopsis enhancer-trap lines for genes expressed in seeds. 29th West Coast Biological Sciences Undergraduate Research Conference, San Diego, CA. <br /> <br /> Homrichhausen, T.M., Liu, P.-P., Nonogaki, H. 2004. Tissue-specific expression of a protein phosphatase 2C in germinated Arabidopsis seeds. The American Society of Plant Biologists Annual Meeting, Orlando, FL.<br /> <br /> Kim, S-H., and A. G. Taylor. 2004. Germinability of film-coated snap bean seed as affected by oxygen diffusion rate under different soil moisture contents. Korean J. of Crop Sci. 49: 46-51. <br /> <br /> Kozareva, I., D.J. Cantliffe, R.T. Nagata and H.J. Klee. 2004. Altered germination of thermosensitive and thermotolerant cultivars of lettuce (Lactuca sativa L.) in response to altered ethylene production. Third International Symposium on Plant Dormancy. Wageningen University, The Netherlands. 25-28 May, 2004.<br /> <br /> Kozareva, I., D. J. Cantliffe, R. T. Nagata, and H. J. Klee. 2004. New support for the involvement of ethylene in lettuce germination at supra-optimal temperature. Acta Horticulturae. Vol. 631. pp. 31-37.<br /> <br /> Kozareva, I., D.J. Cantliffe, R.T. Nagata and H.J. Klee. 2004. Reduced germination of thermotolerant and thermosensitive cultivars of lettuce (Lactuca sativa L.) in reponse to reduced ethylene perception. Third International Symposium on Plant Dormancy. Wageningen University, The Netherlands. 25-28 May, 2004.<br /> <br /> Lee, J.S., W.G. Pill, B.B. Cobb and M.W. Olszewski. 2004. Seed treatments to advance greenhouse establishment of beet and chard microgreens. Journal of Horticultural Science and Biotechnology 79:565-570.<br /> <br /> Leon, R.G., Knapp, A.D., and Owen, M.D.K. 2004. Effect of temperature on the germination of common waterhemp (Amaranthus tuberculatus), giant foxtail (Setaria faberi) and velvetleaf (Abutilon theophrasti). Weed Sci. 52:67-73.<br /> <br /> Leskovar, D.I., M. Cantamutto, P. Marinangelli and E. Gaido. 2004. Comparison of direct-seeded, bareroot, and various tray seedling densities on growth dynamics and yield of long-day onion. Agronomie 24:1-6. <br /> <br /> Li, W., M. B. McDonald, M. A. Bennett, and F. Y. Kwong. 2004. Hydropriming of differing sized impatiens >Expo Wine= seeds. Seed Sci. & Technol. (in press).<br /> <br /> Liu, P.-P., Nonogaki, H. 2004. Screening of Arabidopsis enhancer-trap lines for seed germination-associated genes. The American Society of Plant Biologists Annual Meeting, Orlando, FL.<br /> <br /> McDonald, M.R., A. G. Taylor, J. W. Lorbeer and J. J. van der Heide. 2004. Efficacy testing of onion seed treatments in the greenhouse and field. In C. S. Vavrina and G. E. Welbaum, eds. Proceedings of the Sixth Symposium on Stand Establishment. Acta Horticulturae, 631, 87-93.<br /> <br /> McDonald, M. B., J. Marcos, and J. Wang. 2004. Seed technology training in the year 2004. North-South Americas Molecular Biology Conference.<br /> <br /> McGrath, J.M. 2003. Plant breeding and the promise of genomics. Applied Biotechnology, Food Science and Policy 1:207-211.<br /> <br /> McGrath, J.M., Lewellen, R.T. 2004. Registration of EL0204 sugarbeet germplasm with smooth-root and resistance to rhizomania. Crop Sci. 44: 1032-1033.<br /> <br /> McGrath, J.M., Shaw, R.S., de los Reyes, B.G., Weiland, J.J. 2004. Construction of a sugar beet BAC library from a hybrid that combines diverse traits. Plant Molecular Biology Reporter 22: 23-28.<br /> <br /> Nascimento, W.M., D.J. Cantliffe, and D.J. Huber. 2004. Ethylene evolution and endo-B-mannanase activity during lettuce seed germination at high temperature. Sci. Agr., Vol. 61, pp. 156-163. <br /> <br /> Nault, B. A and A. G. Taylor. 2004. Snap bean B aphid - virus complex: Efficacy of neonicotinoid seed treatments to reduce the incidence of viruses. Bean Improvement Cooperative. 47: 229-230.<br /> <br /> Nault, B. A., A. G. Taylor, M. Urwiler, T. Rabaey and W. D. Hutchison. 2004. Neonicotinoid seed treatments for managing potato leafhopper infestations in snap bean. Crop Protection 23: 147-154. <br /> <br /> Nonogaki, H., Liu, P.-P., Homrichhausen, T.M., Hewitt, J.R., Park, E.J. 2004. Enhancer trap of germination-associated genes in Arabidopsis seeds. 9th International Symposium on Plant Seeds, Meisdorf, Germany. <br /> <br /> Nosarszewski, M., Clements, A.M., Downie, A.B., Archbold, D.D. 2004. Sorbitol dehydrogenase expression and activity during apple fruit set and early development. Physiologia Plantarum 121: 391-398.<br /> <br /> Oakley, K., S. T. Kester, and R. L. Geneve. 2004. Computer- aided digital image analysis of seedling size and growth rate for assessing seed vigour in impatiens. Seed Science and Technology 32:907-915. <br /> <br /> Obendorf, R.L. and Horbowicz, M. 2004. Preparation of fagopyritols and uses therefor (US Patent). United States Patent 6,825,173 B2. Date published: November 30. 48 pages.<br /> <br /> Obendorf, R.L., Odorcic, S. and Gomes, C.I. 2004. Enhancing health-related cyclitols in soy products. Journal of Nutrition 134, 1254S.<br /> <br /> Obendorf, R.L., Odorcic, S., Ueda, T., Coseo, M.P. and Vassallo, E. 2004. Soybean galactinol synthase forms fagopyritol B1 but not galactopinitols: Substrate feeding of isolated embryos and heterologous expression. Seed Science Research 14, 321-333.<br /> <br /> Obendorf, R.L. and Ueda, T. 2004. Fagopyritol synthase genes and uses thereof (International Patent). International Patent Publication Number WO 2004/037974 A2. International Publication Date: 6 May 2004. 170 pages.<br /> <br /> Obendorf, R.L. and Ueda, T. 2004. Fagopyritol synthase genes and uses thereof (US Patent). United States Patent Application Publication US 2004/0038357 A1. Date published: February 26, 2004. 89 pages.<br /> <br /> Olszewski, M.W., T.A. Evans, N.F. Gregory, and W.G. Pill. 2004. Enhanced germination of primed mericarps of parsley (Petroselinum crispum Mill. Nyman ex A.W. Hill) limited by Alternaria alternata proliferation. Journal of Horticultural Science and Biotechnology (in press).<br /> <br /> Olszewski, M.W., W.G. Pill and T.D. Pizzolato. 2004. A modified chromosome squash technique to determine mitotic activity in primed mericarps. Journal of Seed Technology (in press).<br /> <br /> Olszewski, M.W., W.G. Pill and T.D. Pizzolato. 2004. Germination and embryo anatomy of osmotically primed parsley schizocarps. Journal American Society for Horticultural Science 129: 876-880.<br /> <br /> Penaloza, P., G. Ramirez-Rosales, M. B. McDonald, and M. A. Bennett. 2004. Lettuce (Lactuca sativa L.) seed quality evaluation using seed physical attributes, saturated salt accelerated aging and the seed vigor imaging system. Seed Sci. & Technol. (in press).<br /> <br /> Ramirez-Rosales, G., M. Bennett, M. B. McDonald and D. Francis. 2004. Effect of fruit development on the germination and vigor of high lycopene tomato (Lycopersicon esculentum Mill.) genotypes. Seed Sci. & Technol. 32:775-783.<br /> <br /> Rogis, C., L.R. Gibson, A.D. Knapp, and R. Horton. 2004. Can solid matrix priming with GA3 break seed dormancy in eastern gamagrass? J. Range Manage. 57:656-660.<br /> <br /> Rogis, C., L.R. Gibson, A.D. Knapp, and R. Horton. 2004. Enhancing germination of Eastern gamagrass seed with stratification and gibberellic acid. Crop Sci. 44:549-552.<br /> <br /> Sekharan, S., M. B. McDonald, J. G. Streeter, R. T. Sayre, and M. A. Bennett. 2004. Seedling vigor assessment of accelerated and naturally aged soybean seeds. Crop Science Society of America.<br /> <br /> Taylor, A. G., D. H. Paine, N. Suzuki, B. A. Nault and A. McFaul. 2004. Coating technologies for seed treatment applications. In C. S. Vavrina and G. E. Welbaum, eds. Proceedings of the Sixth Symposium on Stand Establishment. Acta Horticulturae, 631, 49-54.<br /> <br /> TeKrony, D. M., T. Schande, M.. Rucker and D. B. Egli. 2004. Effect of seed shape on corn germination and vigor during warehouse and controlled environmental storage. Seed Sci. Technol. (in press).<br /> <br /> Torres, A.C., W.M. Nascimento, S.A.V. Paiva, F.A.S. Aragao, and D.J. Cantliffe. 2004. Bioassay for detection of glyphosate or kanamycin resistance in lettuce plants. Revista Brasileiva de Cultura de Tecidos de Plantes. Vol. 1.<br /> <br /> Trebbi, D., McGrath, J.M. 2004. Fluorometric sucrose evaluation for sugar beet. J. Agricultural and Food Chemistry 52: 6862-6867.<br /> <br /> Walters, C. 2004. Temperature-dependency of molecular mobility in preserved seeds. Biophysical Journal 86: 1253-1258.<br /> <br /> Walters, C., Wheeler, L.J., and Stanwood, P.C. 2004. Longevity of cryogenically-stored seeds. Cryobiology 48: 229-244.<br /> <br /> Wang, H., Caruso, L.V., Downie, A.B., Perry, S.E. 2004. The embryo MADS-domain protein AGL15 directly regulates expression of a gene encoding an enzyme involved in gibberellin metabolism. Plant Cell 16: 1206-1219.<br /> <br /> Wang, T., B.G. Cobb, H. Sittertz-Bhatkar and D.I. Leskovar. 2004. An ultraestructural study of seed reserves in triploid watermelon. Acta Horticulturae (ISHS) 631:71-72.<br /> <br /> Wilson, T.T. and R.L. Geneve. 2004. The impact of film coating on initial water uptake and imbibitional chilling injury in high and low vigor sh2 sweet corn seeds. Seed Science and Technology 32:271-281. <br /> <br /> Xu, Q., Belcastro, M., Dolan, S., Dinkins, R., Clarke, S., Downie, B. 2004. Isolation and characterization of a novel nuclear localized protein repair methyltransferase gene from Arabidopsis thaliana. Plant Physiology 136: 2652-2664.<br /> <br /> Zhao, T.-Y., Martin, D., Meeley, R.B., Downie, B. 2004. Expression of the maize GALACTINOL SYNTHASE gene family: II) Kernel abscission, environmental stress and myo-inositol influences transcript accumulation in developing seeds and callus cells. Physiologia Plantarum 121: 647-655.<br /> <br /> Zhao, T.Y., Thacker, R., Corum, J.W., Snyder, J.C., Meeley, R.B., Obendorf, R.L. and Downie, B. 2004. Expression of the maize GALACTINOL SYNTHASE gene family: (I) Expression of two different genes during seed development and germination. Physiologia Plantarum 121, 634-646.<br />

Impact Statements

1. Post priming protocols will enhance the longevity of primed seeds. This research may lead to methods for extending the storage lives of valuable germplasm.
2. Research in germination, growth rates and stress tolerance will increase speed of crop establishment.
3. Knowledge of freezing point, air temperatures and water availability during seed development will aid seed producers.
4. Discovery of physiological factors that control whether weed or native plants seeds germinate will aid in new methods to control weeds in crops.
5. Research adds to our understanding of the potential use of buckwheat products in the treatment of type II diabetes.

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Report Information

Participants

Phil Allen, Brigham Young Univ.; Mark Bennett, Ohio State Univ.; Kent Bradford, Univ. of California, Davis; Daniel Cantliffe, Univ. of Florida; Feng Chen, Univ. of Tennessee; Marc Cohn, Louisiana State Univ.; Samuel Contreras, Ohio State Univ.; Bruce Downie, Univ. of Kentucky; Robert Geneve, Univ. of Kentucky; Liping He, Ohio State Univ.; Toddy Hu, Ohio State Univ.; Allen Knapp, Iowa State Univ.; Daniel Leskovar, Texas A&M Univ.; Liang-Shiou Lin, USDA/CSREES; Miller McDonald, Ohio State Univ.; Hiro Nonogaki, Oregon State Univ.; Jeff Norcini, Univ. of Florida; Ralph Obendorf, Cornell Univ.; Camille Steber, Washington State Univ.; David Tay, Ohio State Univ.; Alan Taylor, Cornell Univ.; Greg Welbaum, Virginia Tech Univ.

Brief Summary of Minutes

Accomplishments

Objective 1. Pre-harvest stress and seed quality.<br /> <br /> Immature maize seed can suffer severe mechanical and biochemical damage due to freezing of intra- and extra-cellular water prior to harvest. Most hybrid maize seed is produced in the Midwestern states, where fall killing frosts are not uncommon. Populations were constructed, and seed harvested, to evaluate the effects of frost damage at different seed maturities using established seed quality measures. Molecular and physiological measures will be done in 2006. Impact: A tool to precisely measure freezing damage in immature corn seeds is now available. With this tool, researchers can precisely measure the cellular changes with freezing injury and advise producers on the steps to limit or repair damage. (IA)<br /> <br /> Tomato genes that result in elevated lycopene also result in negative pleiotropic effects including slow germination and reduced plant height. It is uncertain whether low gibberellin levels, high ABA content or high light sensitivity account for the reduced speed of germination. This study evaluated gibberellin (GA3), norflurazon (inhibitor of carotenoid and ABA synthesis), and light effects on the speed of germination of the high lycopene tomato line T4099 and its recurrent parent, Flora-Dade. Speed of germination was evaluated as time to reach 50% germination (T50) and germination index. Norflurazon alone and GA3 plus norflurazon resulted in higher speed of germination of T4099 compared to the control but not at the same level as Flora-Dade. These data suggest that T4099 produced greater levels of ABA during imbibition and this process might be regulated by light. Impact: Highly nutritional tomatoes containing the antioxidant lycopene germinate and grow more slowly than traditional varieties, and a high lycopene tomato was shown to have high levels of the plant hormone ABA. Using this knowledge, high lycopene tomatoes with low ABA levels can be obtained, allowing greater production and more healthy dietary choices. (OH)<br /> <br /> A concentrated effort to examine the seed dormancy mechanism of species present in biogeographical regions identified as underrepresented in the 1998 book, Seeds: Ecology, biogeography, and evolution of dormancy and germination, has resulted in several new collaborations world-wide and an increase in the number of represented species for which we have dormancy information from 3580 to 7344. Impact: Seed dormancy is a natural means that plants use to prevent or delay germination until environmental conditions are right for plant survival. This work expands knowledge to aid researchers understand the range of dormancy mechanisms and aid in the preservation of critical ecosytems. (KY)<br /> <br /> For terrestrial orchids, many seeds are not capable of completing germination on media. If seed were harvested prematurely, then the germination was better. Impact: A tool to improve germination of terrestrial orchids has been developed. Using this tool will allow greater consumer access to these orchids as landscape materials and provide a management tool for endangered orchid species to be propagated. (VA)<br /> <br /> Objective 2. Biophysical, biochemical and genetic factors in seed desiccation tolerance and longevity.<br /> <br /> Biochemical changes that occur during seed maturation may provide markers or quantitative indicators of seed maturity and subsequent seed quality. Chlorophyll degradation associated with seed maturity was exploited as a non-destructive method to sort seeds based on chlorophyll fluorescence (CF) from seed coats. In cabbage, both chlorophyll and carotenoid content decreased as seeds matured, but was not affected by ageing. ABA showed a similar trend however, ageing immature seeds decreased ABA content. Tocopherols revealed little differences with respect to seed maturity or ageing. Impact: Sorting good cabbage seed from bad non-destructively has been accomplished. Using this tool will allow seed producers to provide seed of the highest quality to cabbage growers. (NY)<br /> <br /> Crop seeds accumulate soluble carbohydrates as part of their maturation process. In buckwheat seeds, the major soluble carbohydrates are sucrose and galactosides of D-chiro-inositol, named fagopyritols. This study was conducted to determine changes in soluble carbohydrate accumulation in embryos of buckwheat seeds after feeding solutions containing free cyclitols D-chiro-inositol, myo-inositol, and D-pinitol to stem-leaf-seed explants. The results indicate that myo-inositol may be the precursor to D-chiro-inositol synthesis, and fagopyritols accumulated in response to D-chiro-inositol availability in the embryo. We suggest that increasing myo-inositol in buckwheat maternal tissues may be an effective means to enhance the accumulation of D-chiro-inositol and fagopyritols in seeds, compounds that may be beneficial for treatment of non-insulin dependent diabetes mellitus. Impact: Seeds accumulate a complex spectrum of oils, proteins and carbohydrates during seed maturation, and for crops whose product is consumed as seeds, some of these compounds could be medicinally useful. Accumulation of fagopyritol carbohydrates in buckwheat seeds depends on other compounds and the study identified and suggested one means by which fagopyritol accumulation could be enhanced for use in managing diabetes. (NY)<br /> <br /> Lettuce seed germination was observed before seeds reach physiological maturity. Drying seeds at a very early stage did not affect germination, indicating that imposed drying at early stages of seed development will not improve seed germination. Slow drying improved vigor starting slightly later during seed development; however, fast drying decreased vigor. Quality of the seeds in terms of presence of abnormal seedlings was improved with drying. Impact: The lettuce seed crop is dried after harvesting and the drying conditions are critical in maintaining seed quality, however the effect of different drying temperatures and times are critical. Slow drying improved seedling vigor, allowing managers to better control lettuce seed quality. (OH)<br /> <br /> Objective 3. Genes associated with seed development, germination, vigor and dormancy.<br /> <br /> Two lettuce populations are being evaluated to identify genetics of seed dormancy and quality. A recombinant inbred mapping population was evaluated for seed quality phenotypes, including germination at elevated temperatures, germination after red and far-red irradiation, and root and hypocotyl growth. Seventeen significant QTL were identified, and a single locus (Htg6.1) accounted for 25% of the total phenotypic variation for high temperature germination. Nine candidate genes thought to be involved in seed dormancy and germination and 11 genes involved in oil biosynthesis have been mapped. Impact: A complex suite of genes involved seed dormancy and quality has been discovered, allowing researchers to develop new tools to better assess and develop strategies to limit dormancy problems. (CA)<br /> <br /> Brownseed mutants of tomato possess dark testa and deleteriously affect seed germination speed and percentage. Map base cloning strategies are being used to identify the brownseed 1 gene. Recombinants between morphological markers situated on either side of bs1 and sequencing of 200,000 contiguous bases from BACs situated in the region of Chromosome 1 containing the mutant gene are being used for the development of genetic markers and gene discovery. In addition, two of the over-expressed genes responsible for a cold temperature germinating (ctg-D) phenotype have been identified in a genome walk. Impact: Reducing the negative effects that certain genes have on germination could allow more productive varieties to be developed. This work identified three such genes, and tools developed from these genes will allow precise management during variety development to limit their effects. (KY)<br /> <br /> MADS-factors are a large family in plants that directly bind DNA and regulate gene expression. Many members of this family have key developmental roles, and ectopic accumulation of AGL15 promotes somatic embryogenesis. One gene expressed in response to AGL15 encodes an enzyme involved in catabolism of biologically active gibberellins (GAs). High-throughput methods to map AGL15 in vivo binding sites and to assess occupancy of these sites at various developmental stages will identify co-regulated genes. Impact: Certain genes have profound effects on promoting seed and seedling development, and their mechanisms can be central to all plants. This work allows researchers to begin to comprehensively understand the mechanism of the protein called AGL15 and its role in promoting plant development. (KY)<br /> <br /> The BME3 (Blue Micropylar End 3) enhancer-trap line identified a GATA-type zinc finger protein expressed during cold stratification to break seed dormancy. Two independent knockout lines had deeper dormancy than wild-type seeds and exhibited impaired responses to cold treatment. Two GA biosynthesis genes GA20ox3 and GA3ox1 were down-regulated in the knockout seeds, suggesting that the BME3 zinc finger protein is an upstream regulator of GA biosynthesis. Characterization of the BME3 promoter using a GUS reporter gene indicated that this gene is activated in the embryonic axis of germinating seeds. Taken together, the biological function of BME3 is probably to enhance the growth potential of the embryo through the activation of GA biosynthesis in Arabidopsis seeds. Impact: Proteins that have a central role in dormancy and response to cold stress, such as the protein encoded by the BME3 gene, have been recently discovered using modern molecular tools. Using this discovery of BME3, researchers will be able to create a picture of the complex germination process and the factors that affect it. (OR)<br /> <br /> MicroRNAs (miRNA) are 21-24 nucleotide, single-stranded RNA, which negatively regulate expression of transcription factors in plants. To develop this new area of research for seeds, simple miRNA extraction and detection methods were established; small RNAs were purified using isopropanol fractionation and a method to synthesize efficient non-radioactive miRNA probes was developed. As an alternative of miRNA microarrays, a semi-high throughput miRNA detection system using a miniblotter has also been developed. Impact: This is a novel area of study in seed biology and increases the possibility of discovering genes important for seed development, dormancy and germination, which have not been discovered by traditional molecular techniques. MiRNAs and their target genes are highly conserved among diverse species, therefore researchers can directly apply these tools to multiple crops. (OR)<br /> <br /> Endosperm weakening is known to occur in seeds of diverse species including agricultural crop species such as pepper and lettuce. The LeMAN2 gene that encodes a germination-specific endo-²-mannanase is thought to play an important role in endosperm weakening in tomato seeds, which is a prerequisite for radicle emergence in tomato seeds. However, direct evidence for the function of this gene in the induction of seed germination has not been obtained. To further investigate the gene function, RNA interference (RNAi) approach was applied. Regenerated transgenic plants have been tested for antibiotic resistance and transferred to soil. Impact: Germination proceeds through a precise developmental program that requires many proteins to act in concert, some specifically operating during germination with presumably important functions. Weakening of the seed coat is an important step for the seed to germinate, and this research has resulted in a new tool to investigate seed coat weakening that will be used by researchers to reveal additional proteins involved in this complex process. (OR)<br /> <br /> Seed desiccation and germination are developmental stages that are particularly prone to oxidative stress. Glutathione is one of the most abundant and ubiquitous antioxidants in plant cells. To better understand glutathiones role in developing and germinating Arabidopsis seeds, wild-type and a line anti-sense for glutathione reductase2 (anGR2) were compared. anGR2 seeds declined in germination percentage while germination percentage of wild-type seeds increased, during nine months of conventional storage, suggesting seed dormancy or after-ripening had been affected. Impact: Seeds are adversely affected by extremes of temperature and moisture, and often respond with production of antioxidants such as glutathione, whose role in seeds has been inferred to be important for long-term viability. This work indicates that low glutathione levels are detrimental to seed storage, and provides an additional tool for optimal management of seeds in storage. (VA)<br /> <br /> Seeds of the parasitic plant Orobanche require a chemical signal in order to germinate. The seeds are, however, receptive only after several days of conditioning in the presence of water, when metabolic activities take place. Using Differential Display PCR, 62 gene fragments were differentially expressed during conditioning, 54 were sequenced, and 32 resembled known genes. The cDNA of a putative dioxygenase (ACC oxidase) expressed during conditioning encodes a predicted protein of 365 amino acids. Immuno electron microscopy located the putative dioxygenase in embryo dictyosomes. Use of AVG, an ethylene synthesis inhibitor, blocked germination when applied during seed conditioning. Impact: Parasitic weeds germinate and grow on another plant or crop, in response to a chemical signal. Blocking this signal or the response to this signal could prevent germination and provide a strategy for weed control, and this research demonstrated at least one target that would effectively limit parasitic weed seed germination. (VA)<br /> <br /> Objective 4. Technologies to assess seed quality, improve seed performance and enhance seed utilization.<br /> <br /> Seed priming (controlled hydration followed by drying) is used to overcome thermoinhibition in lettuce and to speed germination in a number of species. However, priming often results in a reduction in seed storage life and sensitivity to adverse storage conditions. Studies in lettuce indicated that the rate of drying following priming had some effect on seed longevity, but not sufficient to restore potential longevity to its control level. Assessment of moisture isotherms did not detect a difference between untreated and primed seeds, so a difference in seed moisture content at a given relative humidity cannot explain these results. Additional modifications to the priming protocols are being tested. In addition, as current hypotheses of seed deterioration propose a major role for active oxygen species, tests are being conducted of aging responses in low oxygen atmospheres to determine whether an increased sensitivity to oxygen is associated with more rapid deterioration of primed seeds. Impact: Seed priming increases germination but reduces longevity. Modifications to seed priming methods will overcome this limitation for seed producers. (CA)<br /> <br /> Defining the wheat starchy endosperm proteome and the changes undergone during grain development demonstrates the metabolic versatility of the endosperm and reveals the changing metabolic needs as the grain matures. Prior work has identified thioredoxin target proteins in this tissue and also shown that the solubility of certain resident proteins changes dramatically on reduction by thioredoxin. Impact: The endosperm of wheat provides the grain with many nutritious and baking qualities and further improvements in bread and pasta quality will be directed towards specific protein targets. This research is defining the proteins that contribute to endosperm development and will help plant breeders and millers specify desired improvements. (CA)<br /> <br /> Ethylene synthesis and sensitivity, and their relation to germination at supraoptimal temperatures, were investigated in lettuce (Lactuca sativa L.) seeds matured at 30/20 ºC (day/night) and 20/10 ºC temperatures. Both thermosensitive and thermotolerant seeds matured at 30/20 ºC had greater germination at supraoptimal temperatures, in both light or dark, than seeds matured at 20/10 ºC. Seeds matured at 30/20 ºC produced more ethylene during germination than seeds matured at 20/10 ºC, regardless of imbibition conditions. Seeds matured at 30/20 ºC did not differ from seeds matured at 20/10 ºC in their sensitivity to ethylene. Adding 10 mM of the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid (ACC) to water, increased germination at supraoptimal temperatures of genotypes matured at 30/20 ºC or 20/10 ºC. Impact: Environmental conditions during seed development affect seed germination and seedling growth in an unknown fashion. The current work suggests higher temperatures during seed maturation increase germination at high temperatures in part due to the effect of the plant hormone ethylene, and these results are applicable to seed producers. (FL)<br /> <br /> White corn is a specialty crop, and marketability can be adversely affected by contamination following pollination with yellow corn. Feasibility and efficiency of color sorting in removing adventitious yellow corn from white seed corn with a Satake color sorter was tested. Results indicated that the color sorter significantly reduced the percentage of adventitious yellow seeds at both high and low contamination percentages. Impact: Mechanical seed separation based on color can preserve marketability of white seed when contaminated with yellow seed, and this technology can be readily implemented by seed producers to increase availability and marketability of white corn seed. (IA)<br /> <br /> Seed lots with dormancy cause problems for seed producers and consumers. Practical elements of different germination tests, storage temperatures and different sunflower genotypes were performed to help producers better understand the changing nature of dormancy and gain insight as to mechanisms to predict planting value. The two sunflower genotypes were produced at two sites in two different production years. As expected, genotype and storage temperature affected dormancy level and duration. The standard germination test, utilizing a constant 20C temperature, usually produced the lowest germination while ethylene produced the highest germination. Impact: Variety and storage conditions influence seed dormancy and subsequent germination, and poor germination adversely affects growers economic return. Practical methods to predict high field germination potential are lacking, and the current research will help seed producers refine conditions to minimize and manage risks associated with seed dormancy in commercial seedlots. (IA)<br /> <br /> Soil compaction on soybean seedling emergence was evaluated using seed lots with high germination but variable seedling vigor. Compaction was imposed to the soil after planting in near-cylindrical containers, to provide a range of compactive efforts. As compaction increased from low to high, emergence declined across all seed vigor levels. Emergence of high vigor seed lots remained above 80% until compaction increased to 13.7 kJ m-3, while low vigor seed lots had low emergence (< 50%) at the lowest compaction (4.6kJ m-3). Seed size had no effect on emergence following compaction, however seedling emergence was greater when three seeds were planted in each container compared to one seed. Impact: Most growers face problems associated with their soils at some time, and compaction due to excess water or heavy equipment creates special problems for germinating seedlings. A method was developed to show the effect of seedling vigor with different soil compactions, and can now be applied by other researchers and seed suppliers to manage germination in suboptimal environments. (KY)<br /> <br /> An automated system to measure germination and growth rates using machine vision has been developed. The system uses a flat bed scanner to capture sequential digital images at evenly spaced, user-specified time intervals for seeds germinating in a Petri dish followed by evaluation using computer software. The system can be used to assess germination time courses continuously and automatically on very small seed (Arabidopsis, tobacco) without altering the experimental environment (temperature, light). Impact: A method for non-destructive, repeated measures of seedling growth was developed that will allow seed producers and researchers higher measurement precision. Using this tool, researchers and seed producers will be able to determine the effects of different growth and storage environments on germination. (KY)<br /> <br /> A comparative physiological approach to studying seed death due to drying (recalcitrance) was developed by performing parallel experiments with the recalcitrant Spartina alterniflora and the orthodox S. pectinata. The response of both dormant and non-dormant seeds to flash drying protocols can be readily compared between the two species, as well as comparing the effects of flash versus slow drying. The system permits separation of general drying effects and provides a means to analyze seed parameters in the dormant state, independent of active seed metabolism.. The contribution of peroxidative reactions to recalcitrant seed death was evaluated. There are no contributions to Spartina seed death by thiobarbituric acid-reactive substances (TBARS), ferric orange-xylenol (FOX) reactive substances or hydrogen peroxide. Lipid oxidation does not play a role in seed death due to recalcitrance. Previous reports supporting this idea are incorrect for at least three reasons: (1) TBARS, as commonly performed (without freeze clamping of the tissue) yields artifacts produced during tissue preparation (2) TBARS, as commonly performed, does not correct for interfering phenolics or sugars; correcting for these substances eliminates any significant TBARS, and no differences during the drying of recalcitrant vs. orthodox seeds. (3) FOX products increase during drying of both S. alterniflora and S. pectinata. Impact: A method to evaluate seed death due to drying was developed. Using this method, germplasm curators and ecologists can develop new knowledge and approaches for genetic conservation of important marsh grass and endangered tropical plants. (LA)<br /> <br /> Moisture, temperature, and impedance (the physical constraint of fruit structure and soil type on emergence) contribute to seedling vigor. Temperature effects were examined by germinating sugar beet seeds in water at temperatures ranging from 5C to 35C in 5C increments. Little germination occurred at the most extreme temperatures, with optimal germination occurring from 20C to 25C. Characterization of germination at 15C, 23C, and 35C will give the best discrimination of seedling vigor related to temperature as measured with molecular tools and for selection of high vigor germplasm. Impact: A method to evaluate seedling vigor related to temperature in sugar beet was developed. Using this tool, researchers and seed producers can develop varieties with higher germination and better seedling vigor for growers. (MI)<br /> <br /> A stress test able to predict germination and emergence of sugar beet in the field would be useful to a number workers in the industry, including seeds people, agronomists, breeders, and growers. A number of procedures are available that have some predictive power however field conditions are difficult to mimic in the laboratory. Germination of sugar beet seed in aqueous solutions shows promise as an additional tool for examining seedling vigor. This test was evaluated in a multi-location, multi-institution international trial. One seedlot with high genetic potential and another with low genetic potential was contributed, at the choice and discretion, of participating seed companies. Further, two seedlots for each genetic choice would be tested, one with higher emergence potential (e.g. vigor) and another with lower vigor. The ring test protocol chosen was to germinate 100 seeds in 40 ml of solution in a 250 ml flask at 20 C with constant agitation, with shaking seed on a rotary platform at 100 rpm, with four replications of each entry. Counts of seeds with visible radicles were to be made at 48 h and 96 h after immersion, suggested with a change of solution at the first count time-point. Two solutions would be tested, one of water of discretionary quality and one of 0.3% hydrogen peroxide, freshly prepared. Genetic potential was easily discriminated in water and salt solutions. Seedlot potential was also easy to discriminate in any solution, however the differences were smaller than for genetic potential differences. Impact: A method to predict seedling vigor in water stress environments was validated for sugar beet in an international project. This test can now be widely implemented to ensure growers have high germination performance seed available for planting. (MI)<br /> <br /> Laboratory scale seed coating equipment was developed for seed treatment application, using low volume application and film coating. Adapting seed coating equipment for seed treatment application is one of the W-1168 milestones. This expertise and facilities in seed technology is an integral part of testing and evaluation of new chemistry seed treatments for specialty crops. Impact: Most commercial seed is batch-processed with one or more coatings that provide additional protection or germination benefits to the growers, and this technology was adapted for small quantities of seed in order to examine the effect of coating and different agents on seed performance. This tool will be widely used by seed researchers to evaluate the effect of different coatings to improve germination. (NY) <br /> <br /> Management of onion maggot in onion requires the use of an insecticide applied at planting. Insecticide resistance and a dearth of available products have stimulated an effort to identify new insecticides for onion maggot control, especially chemistries that can be delivered as seed treatments. Onion seeds film-coated with fipronil, spinosad and clothianidin consistently provided excellent control of onion maggot and performed well during wet and dry seasons. Fipronil, spinosad and clothianidin seed treatments should be considered for future registration on onion. Availability of these chemistries would allow rotation with the cyromazine seed treatment, which would likely prolong the longevity of all products. Impact: Seed treatments provide growers with a convenient, reliable, and environmentally responsible method for managing economically damaging onion maggot infestations. New seed treatments that can be used by seed producers were developed that effectively manage insect infestations in onion seed. (NY)<br /> <br /> The effect of selected biologicals on direct seeded and transplanted squash plant growth and mineral content under salinity stress was conducted in pot experiments using a mixture of sandy loam:vermiculite (1:1 v:v) under controlled greenhouse conditions. Biologicals tested included Ag Blend, Soil Builder, Yield Shield, Plant Shield, Behold and Equity. Salinity negatively affected growth of squash; however, biological treatments significantly increased fresh weight compared to nontreated plants that were challenged with salt stress. Furthermore, all biological treatments tested increased the uptake of potassium compared to the nontreated control in both direct seeded and transplanted squash. Sodium concentration was not affected by biologicals in directed seeded squash, while all biologicals, except Plant Shield, decreased sodium uptake in transplants. The most effective biologicals increased the K+/Na+ ratio, which was positively correlated with plant growth. Alteration of mineral uptake may be one mechanism for the alleviation of salt stress. Impact: Many soils have salt concentrations that reduce plant productivity, including germination, and treatments to reduce injury would have wide applicability. A series of bio-treatments were tested in squash for their effect in limiting sodium uptake, and transplants benefited more than direct seed from these products that growers will use to maximize plant production. (NY)<br /> <br /> Development of a Seed Vigor Imaging System (SVIS) continues. A U.S. patent was issued in 2005 for SVIS. The number of crops analyzed by the system has been expanded to include corn, soybeans, cotton, melon, lettuce, tomato, canola and carrot. Progress has also been made in improving the accuracy of the system by minimizing the effect of overlapping seedlings. Impact: An automated seed vigor method for many crops would reduce labor costs in testing seeds. A patent was issued for one system, and this system is being used commercially. (OH)<br /> <br /> The efficiency of an automated computer imaging system was compared to other accepted procedures for the assessment of melon (Cucumis melo L.) seed vigour. Five seed lots each of two cultivars (Oro Rico and Nitro) were subjected to first count germination, accelerated aging (traditional and saturated salt), and speed of seedling emergence tests. Results were compared against those provided by scanning three- and four-day-old seedlings followed by image processing and analysis by specific software that automatically calculated indices for speed and uniformity of seedling growth. Results from the first count germination, accelerated ageing and speed of seedling emergence tests provided consistent identification of the physiological potential of the seed lots, producing information comparable to those for percentage seedling emergence, thus demonstrating their sensitivity for vigor evaluation of melon seeds. Impact: Evaluating seed quality and vigor are labor intensive. An automated system was developed and tested on melon seed germination resulting in a more rapid, objective and efficient alternative for melon seed vigor evaluation by seed technologists. (OH)<br /> <br /> High seed quality is essential for optimum stand establishment in lettuce. As a result, it is necessary to have seed vigor tests that permit rapid, objective and accurate evaluation of seed quality. The standard germination test has been traditionally used to evaluate seed quality of lettuce and other vegetable seeds. However, the standard germination test is conducted under ideal laboratory conditions rarely encountered in the field. This study evaluates physical and physiological seed quality components of four seed lots of six lettuce varieties obtained from a commercial company. Seeds were evaluated for seedling emergence under greenhouse conditions, standard germination, seed physical aspects, the Saturated Salt Accelerated Aging (SSAA) test and the Seed Vigor Imaging System (SVIS). Results indicated that large-seeded lettuce varieties had higher percentage germination, higher SSAA values, higher SVIS index and more rapid and uniform greenhouse emergence. Black-seeded lettuce varieties possessed higher seed quality and less fungal invasion when evaluated by the SSAA test. Impact: Standard germination tests conducted under ideal laboratory conditions are rarely encountered in the field, and a stress germination test would be widely used in the seed industry. For lettuce, an index was determined that was significantly correlated with seedling emergence under greenhouse conditions, allowing researchers and seed suppliers an easy measure of seed vigor. (OH)<br /> <br /> Priming effects may be different among impatiens seed lots with different seed sizes. To investigate this relationship, six seed size classes of Expo Wine impatiens seeds were hydroprimed for different durations followed by slow dehydration using saturated salt solutions. Germination results showed that 24, 36 and 42h of hydropriming reduced speed of germination, while 4 and 8h of hydropriming promoted speed of germination and 1h hydropriming showed no significant difference compared to non-primed seeds. Statistical analysis indicated that seed size effects existed, with larger seeds germinating faster than smaller seeds following hydropriming. Impact: Uniformity of germination and seedling growth of landscape bedding plants is essential to maximize grower return, and methods to improve germination were re-evaluated. The timing of one treatment, hydropriming, was shown to be critical, and seed suppliers can now incorporate a short-duration hydopriming step in order to improve seed quality in impatiens.(OH)<br /> <br /> Desiccation and temperature stress are two major stressors that often limit seedling establishment. The ability of transplants to tolerate transplant shock and resume growth is often determined by the balance between root water uptake and leaf transpiration, and is linked to shoot/root growth. New industry efforts in the development of compounds for improving transplant performance have broadened opportunities for research in vegetable species. We investigated the influence of physiological (abscisic acid, ABA) and physical (AntiStress, Transfilm and Vapor Gard) antitranspirants on the growth and physiology of pepper seedlings exposed to one or two cycles of desiccation. Root application of ABA enhanced desiccation tolerance compared to foliar application. Leaf photosynthesis and conductance decreased upon ABA application, however photosynthesis rates recovered after 7 days. Throughout two cycles of desiccation, ABA had a stronger effect in reducing stomatal conductance and photosynthesis while increasing leaf and stem water potential compared to physical antitranspirants. Most transplant growth changes occurred at the shoot level, and the control of shoot growth by ABA appeared to be transient. Signaling or metabolic compounds appeared more efficient to modulate shoot growth and enhance stress tolerance than physical compounds. Impact: High-value crops are often transplanted into the field, but transplant shock can limit production. Various pre-transplant seedling treatments to reduce shock and allow quick resumption of growth were tested, and growers can now better manage transplant shock in pepper. (TX)<br /> <br /> Silenis vulgaris is a wild plant originated in central Europe with medicinal and horticultural properties, and can be used to extract heavy metals for phytoremediation. Temperature and salinity regimes were evaluated on Silenis germination. Maximum germination occurred between 2.5 and 5.0 dS m-1 (99%), with a slide reduction at 10 and 12.5 dS m-1 (88-83%). There was a direct relationship between mean days of germination (3 to 8 days) and EC concentration (0 to 12.5 dS m-1). These responses were independent of incubation temperatures (15-25°C range). Impact: Collecting wild plants for medicianal uses is impractical and detrimental to the environment, and bringing them into cultivation is one solution. This work demonstrates conditions where one such wild species can be germinated, and allows researchers and plant breeders to now determine its potential for cultivation. (TX)<br /> <br /> Fruit color and carotenoid composition are important traits in watermelon. Watermelon fruit color inheritance studies have revealed that several genes are involved in color determination. Differential gene activities in the carotenoid biosynthetic pathway may result in different color determination of mature fruit. Genes encoding enzymes in the carotenoid biosynthetic pathway were isolated and characterized to provide fundamental genetic information. We developed a PCR-based molecular marker to distinguish fruit color between canary yellow and red. Impact: Development of reliable molecular markers will facilitate watermelon breeding and allow breeders to distinguish harvested flesh color and nutritional profiles at the seedling stage or even within a seed. (TX)<br /> <br /> Future Plans<br /> <br /> Plans for the W-1168 to host an international Translational Seed Biology Symposium were advanced, as a vehicle to bridge emerging insights of basic seed biology research for practical agricultural and ecological utilization of seeds and seed products. The location and date need to be decided. Proceedings will be published, and are expected to have a broad impact towards defining problem-solving approaches using emerging technologies.<br />

Publications

Adams, C.A., J.M. Baskin, and C.C. Baskin. 2005. Comparative morphology of seeds of closely-related species of Aristolochia subgenus Siphsia (Aristolochiaceae, Piperales.) Bot. J. Linnean Soc. 148: 433-436. <br /> <br /> Adams, C.A., J.M. Baskin, and C.C. Baskin. 2005. Trait stasis versus adaptation in disjunct relict species: evolutionary changes in seed dormancy-breaking and germination requirements in a subclade of Aristolochia subgenus Siphisia (Piperales). Seed Sci. Res. 15: 161-173.<br /> <br /> Alekseichuk, H., A. G. Taylor, and R. Parker. 2005. Isoprenoid PathwayProducts in Relation to Cabbage Seeds Maturation and Quality 8th International Workshop on Seeds "Germinating New Ideas" (8-13 May 2005, Brisbane, Queensland, Australia). P.107.<br /> <br /> Alvarado, V., and Bradford, K.J. 2005. Hydrothermal time analysis of seed dormancy in true (botanical) potato seeds. Seed Science Research 15: 77-88. [In press last report.]<br /> <br /> Argyris, J., Truco, M.J., Ochoa, O., Knapp, S.J., Still, D.W., Lenssen, G.M., Schut, J.W., Michelmore, R.W., and Bradford, K.J. 2005. Quantitative trait loci associated with seed and seedling traits in Lactuca. Theor. Appl. Genet. 111: 1365-1376.<br /> <br /> Argyris, Jason, Dennis TeKrony, Don Hershman, David Van Sanford, Marla Hall, Brenda Kennedy, Marcy Rucker and Cheryl Edge. 2005. Fusarium head blight infection following point inoculation in the greenhouse compared to movement of Fusarium graminearum in seed and floral components. Crop Sci. 45: 626-634.<br /> <br /> Bang, H., S. Kim, D.I. Leskovar and S. King. 2005. Genotype analysis of fruit color using a molecular marker in watermelon. HortScience 40(4):1114.<br /> <br /> Bang, H.J. 2005. Environmental and genetic strategies to improve carotenoids and quality in watermelon. Ph.D. Thesis, Texas A&M University<br /> <br /> Baskin, C.C. and J.M. Baskin. 2005. Seed dormancy in wild flowers. pp. 163-185. In M. B. McDonald and F. Kwong (eds.), Flower Seeds: Biology and technology. CABI Wallingford, UK.<br /> <br /> Baskin, C.C. and J.M. Baskin. 2005. Underdeveloped embryos in dwarf seeds and implications for assignment to dormancy class. Seed Sci. Res. (in press). [have read proof, will be in next issue]<br /> <br /> Baskin, C.C., J.M. Baskin, A. Yoshinaga and K. Thompson. 2005. Germination of drupelets in multi-seeded drupes of the shrub Leptecophylla tameiameiae (Ericaceae) from Hawaii, a case for deep physiological dormancy broken by high temperatures. Seed Sci. Res. (in press). [have read proof, will be in next issue]<br /> <br /> Baskin, J.M., C.C. Baskin, and R.W. Tyndall. 2005. Studies on dormancy, germination, and survival of seeds buried in soil of the rare plant species Aeschynomene virginica (Fabaceae). Nat. Areas J. 25: 147-155.<br /> <br /> Bonina, J. and D. J. Cantliffe. 2004. Seed production and seed sources of organic vegetables. HS 981. EDIS http://edis.ifas.ufl.edu. <br /> <br /> Bonina, J.R.. 2005. A rapid, simple, inexpensive and reproducible endo-beta-mannanase assay test for determining optimal hydrothermal timing of commercial priming of lettuce seed. Masters Thesis, University of Florida. <br /> <br /> Cong Zhu and Sharyn E. Perry. (2005) Control of expression and autoregulation of AGL15, a member of the MADS-box family. The Plant Journal 41, 583-594.<br /> <br /> Cong Zhu, Ph.D. 2005. Title: Gene Regulatory Networks of AGL15, A Plant MADS Transcription Factor. Ph.D. Thesis, University of Kentucky<br /> <br /> Dale, T.M, McGrath, J.M., Renner, K.A. 2005. Response of sugarbeet varieties and populations to postemergence herbicides. Journal of Sugarbeet Research 42:119-126.<br /> <br /> Egli, D. B., D. M. TeKrony and J. F.Spears. 2005. High temperature stress and soybeanseed quality: Stage of seed development. Seed Technol. 27: 177-189.<br /> <br /> Egli, D. B., D. M. TeKrony, J.J. Heitholt and J. Rupe. 2005. Relationship between air temperature during seed filling and seed germination and vigor in soybean. Crop Sci. 45: 1329-1335. <br /> <br /> Gandhi, S., Heesacker, A., Freeman, C., Argyris, J., Bradford, K.J., Knapp, S.J. 2005. The self-incompatibility locus (S) and quantitative trait loci for self-pollination and seed dormancy in sunflower. Theor Appl Genet. 111: 619-629. [In press last report.]<br /> <br /> Geneve, R.L. 2005. Vigor testing in flower seeds. In: M.B. McDonald and F. Kwong (eds.). Flower Seeds, Biology and Technology. CAB International, London. p.p. 311-332.<br /> <br /> Gomes, C.I. 2005. Transport of myo-inositol, D-pinitol, and D-chiro-inositol in soybean (Glycine max (L.) Merrill) plants. Senior Plant Biology Honors Thesis, Cornell University (May 2005), Ithaca, NY, 61 pages. <br /> <br /> Gomes, C.I., Obendorf, R.L., Horbowicz, M. 2005. myo-Inositol, D-chiro-inositol, and D-pinitol synthesis, transport, and galactoside formation in soybean explants. Crop Sci. 45:1312-1319.<br /> <br /> Haagenson, D.M., Klotz, K.L., McGrath, J.M. 2005. Sugarbeet sucrose synthase genes differ in organ-specific and developmental expression. Journal of Plant Physiology 163:102-106.<br /> <br /> Hawkins, T.S., J.M. Baskin, and C.C. Baskin. 2005. Life cycles and biomass allocation in seed- and ramet-derived plants of Cryptotaenia canadensis (Apiaceae), a monocarpic species of eastern North America. Can. J. Bot. 83: 518-528.<br /> <br /> Hidayati, S.N., J.M. Baskin, C.C. Baskin. 2005. Epicotyl dormancy in Viburnum acerifolium (Caprifoliaceae). Amer. Midl. Nat. 153: 232-244.<br /> <br /> Hoffmaster, A. F., L. Xu, K. Fujimura, M. B. McDonald, M. A. Bennett and A. F. Evans. 2005. The Ohio State University Seed Vigor Imaging System (SVIS) for soybean and corn seedlings. J. Seed Technol. 27:7-26.<br /> <br /> Horbowicz, M., Obendorf, R.L. 2005. Fagopyritol accumulation and germination of buckwheat seeds matured at 15, 22, and 30 C. Crop Sci. 45:1264-1270.<br /> <br /> Hyatt, Jessica. 2005. Relationship of soil compaction to soybean seedling emergence. M.S. Thesis, University of Kentucky <br /> <br /> Kucera, B., Cohn, M.A. and Leubner-Metzger, G (2005) Plant hormone interactions during seed dormancy release and germination. Seed Science Research 15, 281-307.<br /> <br /> Li, W., M. B. McDonald, M. A. Bennett, and F. Y. Kwong. 2005. Hydropriming of differing sized impatiens Expo Wine seeds. Seed Sci. & Technol. 33:639-646.<br /> <br /> Liu, P.-P., Koizuka, N., Homrichhausen, T.M., Hewitt, J.R., Martin, R.C. and Nonogaki, H. (2005) Large scale screening of Arabidopsis enhancer-trap lines for seed germination-associated genes. The Plant Journal 41, 936-944.<br /> <br /> Ma, J.M., Horbowicz, M., Obendorf, R.L. 2005. Cyclitol galactosides in embryos of buckwheat stem-leaf-seed explants fed D-chiro-inositol, myo-inositol, or D-pinitol. Seed Sci. Res. 15:329-338.<br /> <br /> McDonald, M. B. 2005. Flower seed deterioration. In: Flower Seeds: Biology and Technology (eds. M. B. McDonald and F. Kwong). CABI Publishing Co., Wallingford, UK.<br /> <br /> McDonald, M. B. and F. Kwong (editors). 2005. Flower Seeds: Biology and Technology. CABI Publishing Co., Wallingford, UK.<br /> <br /> McDonald, M. B., K. Fujimura, M. A. Bennett, Y. Sako and A. F. Evans. 2005. System and method for determining a seed vigor index from germinated seedlings by automatic separation of overlapped seedlings. U. S. Patent 6,882,740 B1. Date of patent: April 19, 2005.<br /> <br /> McGrath, J.M. 2005. ARS makes headway on varietal development: How the research filters down to commercial sugarbeet seed companies. Sugar: The Sugar Producer Magazine. November 2005. 16-18.<br /> <br /> McGrath, J.M. 2005. Deployment of Beta genetic resources. In Report of a Working Group on Beta and World Beta Network. Second joint meeting, 23-26 October 2002, Bologna, Italy (L. Frese, C. Germeier, E. Lipman, and L. Maggioni, compilers). International Plant Genetic Resources Institute, Rome, Italy. Pp. 108-110.<br /> <br /> McGrath, J.M. 2005. Genomics in Genetic Improvement. In: Biancardi, E., Campbell, L., Skaracis, G.N., de Biaggi, M. (eds) Genetics and Breeding of Sugarbeet. Science Publishers, Inc., New Hampshire, USA. Pp. 221-234.<br /> <br /> McGrath, J.M. 2005. Notice of release of EL53 sugarbeet germplasm with smooth-root and improved resistance to Rhizoctonia crown and root rot. USDA-ARS Germplasm Release Notice.<br /> <br /> McGrath, J.M. 2005. Variety choice important for bettering bottom line: Gene research tough challenge. Sugar: The Sugar Producer Magazine. January 2005. 18-19.<br /> <br /> McGrath, J.M., Biancardi, E. 2005. Sugar content, root weight, and sugar yield. In: Biancardi, E., Campbell, L., Skaracis, G.N., de Biaggi, M. (eds) Genetics and Breeding of Sugarbeet. Science Publishers, Inc., New Hampshire, USA. Pp. 119-122.<br /> <br /> McGrath, J.M., Koppin, T.K., Duckert, T.M. 2005. Breeding for genetics: Development of Recombinant Inbred Lines (RILs) for gene discovery and deployment. Proceedings of the American Society of Sugar Beet Technologists, March 2-5, 2005. pp 124-132.<br /> <br /> McGrath, J.M., Trebbi, D. 2005. Notice of release of TBEL1 table beet germplasm with high sweetness and cylindrical shape. USDA-ARS Germplasm Release Notice.<br /> <br /> Moineddin, Z. M., C. D. Scott Dupree, C. R. Harris, A. G. Taylor, and M. R. McDonald. 2004. Integrated Management of Onion Smut (Urocyctis cepulae Frost) and Onion Maggot (Delia antiqua (Meigen)) with reduced risk seed treatments. Root, Bulb and Leafy Vegetable Report 2005.<br /> <br /> Montgonery, J. 2005. Evaluation of solid artificial media for lettuce seedling growth and anchorage. MS thesis. Cornell University.<br /> <br /> Obendorf, R.L., McInnis, C.E., Horbowicz, M., Keresztes, I., Lahuta, L.B. 2005. Molecular structure of lathyritol, a galactosyl bornesitol from Lathyrus odoratus seeds, by NMR. Carbohydr. Res. 340:1441-1446.<br /> <br /> Obendorf, R.L. and Gore, M.G. 2005. Physiology of maize kernel quality development (abs. 54-5) [part of Div. C-2 Symposium--The Physiology Behind Crop Quality]. Abs. Internat. Annu. Meeting Crop Sci. Soc. Amer. 2005:2545 (54-5).<br /> <br /> Phartyal, S.S., J.M. Baskin, C.C. Baskin, and R.C. Thapliyal. 2005. Physical dormancy in seeds of Dodonaea viscosa (Sapindaceae) from India. Seed Sci. Res. 15: 59-61.<br /> <br /> Ramirez-Rosales, G., M. A. Bennett, M. B. McDonald and D. Francis. 2005. Gibberellin plus norflurazon enhance the germination of a dark green tomato genotype. J. Seed Technol. 27:59-65.<br /> <br /> Ramirez-Rosales, G., M. Bennett, M. B. McDonald, D. Francis and S. Contreras. 2005. Total antioxidant capacity of fruit and seeds from normal and enhanced lycopene tomato (Lycopersicon esculentumI Mill.) genotypes. J. Seed Technol. 27:66-75.<br /> <br /> Reschly, B. L. 2005. Dormancy regulation in conventional and oleic sunflower lines (Helianthus annuus L.). Masters Thesis. Iowa State University.<br /> <br /> Salaita L, Kar RK, Majee M, Downie AB. 2005. Identification and characterization of activation tagged Arabidopsis mutants exhibiting rapid seed germination. J. Exp. Bot. 56: 2059-2069.<br /> <br /> Sánchez, M.P., Gurusinghe, S.H., Bradford, K.J., and Vázquez-Ramos, J.M. 2005. Differential response of PCNA and CDK-A proteins and associated kinase activities to benzyladenine and abscisic acid during maize seed germination. J. Exp. Bot. 56: 515-523 [In press last report.]<br /> <br /> Schwember, A.R., and Bradford, K.J. 2005. Drying rates following priming affect temperature sensitivity of germination and longevity of lettuce seeds. HortScience 40: 778-781. [In press last report.]<br /> <br /> Sekharan, S. 2005. Aged soybean (Glycine max [L.] Merr.] seeds  Their physiology and vigor assessment. Thesis, Ohio State University, Columbus, OH.<br /> <br /> Tanja M. Homrichhausen. (2005) Molecular mechanisms of embryo development and germination in plants. Honors thesis, Oregon State University.<br /> <br /> TeKrony, D. M., T. Schande, M. Rucker and D. B. Egli. 2005. Effect of seed shape on corn germination and vigor during warehouse and controlled environmental storage. Seed Sci.Technol. 33: 185-187. <br /> <br /> Treated Seeds Show Promise Against Pests. AgNews, News and Public Affairs, Texas A&M University System Agriculture Program. agnews.tamu.edu/dailynews/stories/ENTO/Oct2405a.htm<br /> <br /> Turner, R., D.J. Merritt, C.C. Baskin, K.W. Dixon, and J.M. Baskin. 2005. Physical dormancy in seeds of six genera of Australian Rhamnaceae. Seed Sci. Res. 15: 51-58. <br /> <br /> Ueda, T., M.P. Coseo, T.J. Harrell, and R.L. Obendorf. 2005. A multifunctional galactinol synthase catalyzes the synthesis of fagopyritol A1 and fagopyritol B1 in buckwheat seed. Plant Sci. 168:681-690. <br /> <br /> Vensel, W.H., Tanaka, C.K., Nai, N., Wong, J.H., Buchanan, B.B. and Hurkman, W.J. 2005. Developmental changes in the metabolic protein profiles of wheat endosperm. Proteomics 5: 1594-1611.<br /> <br /> Woltz, James M., Dennis B. Egli and Dennis M. TeKrony. 2005. Freezing point temperatures of corn structures during seed development. Agron. J. 97: 1564-1569.<br /> <br /> Wong, J.H., Cai, N., Balmer, Y., Tanaka, C.K., Vensel, W.H., Hurkman, W.J. and Buchanan, B.B. 2004. Identification of thioredoxin targets in developing wheat seeds using complementary proteomic approaches. Phytochemistry 65: 1629-40.<br /> <br /> Wong, J.H., Cai, N., Tanaka, C.K., Vensel, W.H., Hurkman, W.J. and Buchanan, B.B. 2004. Thioredoxin reduction alters the solubility of proteins of wheat starchy endosperm: An early event in germination. Plant Cell Physiol. 45: 407-415.<br /> <br /> Xu Q, Zhang D, Downie B. 2005. Rapid and efficient subcloning of DNA without dephosphorylation or gel electrophoresis. Molecular Biotechnology 29: 111-118.<br /> <br /> Yildirim, E. and A. G. Taylor. 2005. Effect of biological treatments on growth of bean plants under salt stress. Bean Improvement Cooperative. 48.<br />

Impact Statements

1. Highly nutritional tomatoes containing the antioxidant lycopene germinate and grow more slowly than traditional varieties, and a high lycopene tomato was shown to have high levels of the plant hormone ABA. Using this knowledge, high lycopene tomatoes with low ABA levels can be obtained, allowing greater production and more healthy dietary choices.
2. A tool to improve germination of terrestrial orchids has been developed. Using this tool will allow greater consumer access to these orchids as landscape materials and provide a management tool for endangered orchid species to be propagated.
3. The lettuce seed crop is dried after harvesting and the drying conditions are critical in maintaining seed quality, however the effect of different drying temperatures and times are critical. Slow drying improved seedling vigor, allowing managers to better control lettuce seed quality.
4. Reducing the negative effects that certain genes have on germination could allow more productive varieties to be developed. This work identified three such genes, and tools developed from these genes will allow precise management during variety development to limit their effects.
5. Proteins that have a central role in dormancy and response to cold stress, such as the protein encoded by the BME3 gene, have been recently discovered using modern molecular tools. Using this discovery of BME3, researchers will be able to create a picture of the complex germination process and the factors that affect it.
6. Seeds are adversely affected by extremes of temperature and moisture, and often respond with production of antioxidants such as glutathione, whose role in seeds has been inferred to be important for long-term viability. This work indicates that low glutathione levels are detrimental to seed storage, and provides an additional tool for optimal management of seeds in storage.
7. The endosperm of wheat provides the grain with many nutritious and baking qualities and further improvements in bread and pasta quality will be directed towards specific protein targets. This research is defining the proteins that contribute to endosperm development and will help plant breeders and millers specify desired improvements.
8. Mechanical seed separation based on color can preserve marketability of white seed when contaminated with yellow seed, and this technology can be readily implemented by seed producers to increase availability and marketability of white corn seed.
9. A method for non-destructive, repeated measures of seedling growth was developed that will allow seed producers and researchers higher measurement precision. Using this tool, researchers and seed producers will be able to determine the effects of different growth and storage environments on germination.
10. A method to predict seedling vigor in water stress environments was validated for sugar beet in an international project. This test can now be widely implemented to ensure growers have high germination performance seed available for planting.
11. An automated seed vigor method for many crops would reduce labor costs in testing seeds. A patent was issued for one system, and this system is being used commercially.
12. High-value crops are often transplanted into the field, but transplant shock can limit production. Various pre-transplant seedling treatments to reduce shock and allow quick resumption of growth were tested, and growers can now better manage transplant shock in pepper.
13. Seeds accumulate a complex spectrum of oils, proteins and carbohydrates during seed maturation, and for crops whose product is consumed as seeds, some of these compounds could be medicinally useful. Accumulation of fagopyritol carbohydrates in buckwheat seeds depends on other compounds and the study identified and suggested one means by which fagopyritol accumulation could be enhanced for use in managing diabetes.

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Report Information

Participants

Phil Allen, Brigham Young Univ.;
Kent Bradford, Univ. of California, Davis;
Marc Cohn, Louisiana State Univ.;
Bruce Downie, Univ. of Kentucky;
Brian Duggan, Oregon State Univ.;
Robert Geneve, Univ. of Kentucky;
Daniel Leskovar, Texas A&M Univ.;
Miller McDonald, Ohio State Univ.;
Mitch McGrath, Michigan State Univ.;
Hiro Nonogaki, Oregon State Univ.;
Jeff Norcini, Univ. of Florida;
Julia Solanenka, Cornell Univ.;
Camille Steber, Washington State Univ.;
Alan Taylor, Cornell Univ.;
Greg Welbaum, Virginia Tech Univ.

Brief Summary of Minutes

Minutes: W-1168 Annual Meeting

Environmental and Genetic Determinants of Seed Quality and Performance
(December 02-03, 2006, Texas A&M University, San Antonio, Texas)

Saturday, December 02.

Chairperson Mitch McGrath called the meeting to order and welcomed all participants and handed over to Daniel. Immediate Past Chairperson Daniel Leskovar (host) repeated the welcome.

1. Leskovar went through the agenda for the meeting.
2. Leskovar went over the arrangements for rides back to the airport on Sunday.
3. McGrath: Nominations for Secretary for 2007 and Nomination Committee should be decided before lunch.
4. McGrath: Rewrite committee is also needed as well as the Symposium Committee.
5. Leskovar: Introduced speaker: Dr. Tim Davis, Department Head, Texas A&M, gave a presentation commencing with a welcome to Texas.
6. McGrath: Minutes of the meeting for 2005. Kent Bradford moved the minutes be approved, Miller McDonald seconded that motion, which passed unanimously.
7. McGrath: Requested that the state reports be due in a couple of weeks, preferably delivered in electronic format. If you go to the ARS website, you can get to our W-1168 reports. After Hiro summarizes the state reports they are placed on that web page.
8. McGrath: Brought up that the current W-1168 working group project runs from 2003-2008. The renewal of the project proposal will have to happen this coming year (2007). Mitch went through the four objectives that are listed on the web site in the current statement of objectives. The rewrite is pending for January 2008. The objectives from the last rewrite, are they OK for the next iteration?

Discussion
- Greg Welbaum wanted to know what the current format looks like. Have there been changes because this will influence how we write.
- Marc Cohn: We can get help from our USDA administrative advisor on this. A new title is necessary.
- Bradford: Do we need to evaluate the new people, who will we lose, who will we appeal to?
- MacDonald: Correct, we need to get those outside the group into the group.
- Welbaum: Correct, there is a seed investigation center at Virginia Tech that Greg knew nothing about and there is a disconnect that must be fixed.
- Bob Geneve: Our focus has changed from agronomy to horticulture.
- MacDonald: The agronomy people are not being replaced. No emphasis on row crops in the future rather it will be on model systems.
- Phil Allen: Asked about the graduate students at Texas A&M, how many coming from industry?
- Leskovar: 40%.
- Allen: International breakdown?
- Leskovar: 60% US, 40% other.
- Bradford: We have to write the project this year.
- McGrath: First step is to write a request for renewal. Mitch wants a couple of people to help determine how to do this.
- Bradford: We need to come out of this meeting with a definite Rewrite Committee so we can get them to push us to have something ready.
- McGrath: We will ask for nominations tomorrow.
- Welbaum: We can use the Davis symposium to meet.
- Cohn: Good idea.
- Bradford: We could meet ahead of time.
- Allan: How important is our USDA rep in getting approval?
- McDonald/Bradford: Dick Heimsch was a great advocate for us.
- Leskovar: How long is a typical USDA rep appointment?
- McDonald: A pleasure to work with Dorcus.

General consensus.

- Bradford: If we met in September 2007, would that be our annual meeting?
- McGrath: That would be a decision regarding the venue for 2007, it would be California.
- Leskovar: Would it qualify for 2008?
- Bradford/McDonald: Probably.
- Cohn: Our reporting basis is the fiscal year and we are close enough for that.
- Bradford: True.
- Cohn: Certainly efficient.
- Bradford: The symposium is a major activity for the group to report. If there are any other publications that come out of it, so much the better.

McGrath will check with Paul Rasmussen to determine if we can meet in Sept. and have it count for 2008.

- McGrath: Daniel was chair, Mitch is chair and Hiro is secretary. Hiro will be the vice-chair in 2008, Bruce will be the secretary.
- Bradford: I nominate myself and Miller as nominating committee for the secretary.
- McGrath: Marc moved and Camille seconded the motion that Kent and Miller would be the nominating committee.
- Cohn: No need for a site committee.

General Consensus: Logistics would not be a problem.

Conclusion, pending Paul Rasmussen's approval: We will have the 2007 W-1168 meeting before the Symposium at UC Davis, Kent Bradford hosting.

9. Moving on to the 2007 Symposium as it currently stands. Presenter: Kent Bradford, UC Davis (see appended symposium schedule).

Rational: Two groups of people that don't communicate. Model plant versus practical.

Symposium title: Translational Seed Biology: From Model Systems to Crop Improvement.

The title was discussed and generally approved.

Funding:
John Harada and Kent Bradford: NSF: Kent. USDA: John.
More efficient to put the grants through UC Davis. Anyone who wants to help write it is welcome.

USDA: $10,000
BioStar: $15,000 Travel for anyone within California is paid separately and will be off budget.
College: $15,000 requested.
Department: $25,000 committed.

Idea: Enough money to have no charge for graduate students at Davis. Also, no charge for local faculty to come to the scientific venue.

Discussion:
- McDonald: Karen Koster mentioned that ISSS might be able to support some of the activities.
- Bradford: Only about $1,000 but it would be worth doing.
- McDonald: Lower costs is better for graduate students.
- Bradford: Companies might sponsor lunch/coffee.
- McGrath: Where on campus?
- Bradford: Freeborn Hall. Flat seating with a stage, but the better auditoriums would necessitate moving elsewhere to do the posters, etc., food, bookstore, everything is within walking distance, including hotels.

Program:

Rob Horsch is the first choice. If we can't get him then who?
Bob Goldberg has accepted.

Discussion

- McDonald: Why are big seeds needed?
- Bradford: Presumably they are breaking the negative correlation. Bigger seeds without decreasing yield.
- McDonald/Bradford: Presumably, seed size was restricted by sink strength. Harada/Fischer, etc., claim the same thing for Arabidopsis.
- Geneve: Order of the presentation, why not have the second session all on seed size? This would mean moving Anna and Brian in the schedule.

Reserve Accumulation:

- Geneve: Lipid is all for human consumption or is it biofuels?
- Bradford: Don't know but probably biofuels.
- Geneve: If so, then hit DOE for money.

General consensus.

Desiccation Tolerance, Longevity and Vigor.

- Geneve: How long?
- Bradford: 30 minutes, in stone! Moderator roles for all present W-1168 members.

Dormancy and Germination.

Translation to the Marketplace.

- McGrath: Fred Bliss is a suggestion from Mitch.
- Welbaum: Could we get someone from Africa to end the program?
- Bradford: This is a thought.

Consensus: A VERY exciting program of the best in the world.
General comments on symposium:

- Geneve: What happened to the question and answer sessions?
- Bradford: At the end of every session, there will be a Q&A for 20-30 minutes.
- Allan: Will there be questions after each talk?
- Bradford: 5 minutes if everyone sticks to 25 minutes.
- Bradford: We could organize a tour up into the valley, watermelon harvesting.
- Welbaum: Posters are pretty much volunteer?
- Bradford: Correct. Lunches and end second day are the only poster viewing times so not a lot of time but better than nothing.
- Geneve: Q&A sessions: Difficult with international people to ask questions clearly.
- Bradford: Just plan to have microphones out in the audience.
- Cohn: The morning of Sept. 20th, four speakers in less than 2 hours?
- Bradford: A choice has to be made.

BREAK!

Resumption at 10:40 a.m.

Response to general discussion.

Outcome a deliverable and no manuscripts requested from the participants.

- Jeff Norcini: Construct a web site.
- Cohn: A Seed Biology web site.
- Bradford: The UC Davis IT will set up a web site.
- Camille Steber: A posteriori could make a review of the meeting topics/ideas. Meeting report for plant phys/plant cell. Should there be a follow up with some of the authors?
- Cohn: What about a series of invited reviews, two to an issue, from the meeting members in SSR?

General Consensus: Good idea.

- Bradford: We can put a review together that they can buy into.
- Welbaum: Breeze presentation or taped audio with slide presentation. Write it up and see if they sign off on it.
- Geneve: Look at the funding agencies to determine if they require a deliverable.
- Cohn: It would be a product for more than just the participants.
- Bradford: We have a meeting just before so we can delegate jobs at the meeting.
- Bradford: Some type of identity for W-1168. Poster sessions would be of value to the group, perhaps small format poster printouts for the compendium. Funding for student travel. We can advertise there is money for graduate students and then see who and how many request funding. Two tier registration system.
- Geneve: Needs to be advertised ASAP.
- Bradford: Definitely. The ISSS logo must be on some part of the meeting, this might get us free advertising in SSR.
- Leskovar/Bradford: We need to get the associations to put it on their web sites.
- McGrath: Web site?
- Bradford: UC Davis IT will do it.
- Allan: How many people came to Fort Collins?
- Bradford: Don't know. Expect 200 people.
- Geneve: Dates of the meeting make it difficult.
- Bradford: True, but we have to live with it.
- Welbaum/Leskovar/Brian Duggan: Send an e-mail to ASHS, etc., requesting sponsorship and advertisement.
- Duggan: When will we have to finalize costs?
- Bradford: When we set the registration price.
- Norcini/Cohn: When are the grant results announced?
- Bradford: This has to be delegated.
- Cohn: Might be worth contacting the panel manager, it may shorten the decision time.
- Bradford: Yes, I will contact the panel managers.
- Geneve: Rockefeller and Gates Foundations are on the agenda, what about having them pony up?
- Bradford: Yes, good idea.

10: Project Rewrite Discussion

- McGrath: Do you want to have a discussion of the rewrite or other business? Maybe go through the themes and see if the broad topic themes are OK for the next iteration?
- Geneve: Can we use these or should we use these? The more objectives you have the more work, can we reduce this to three?
- McDonald: Reduction to two or three creates vagueness. Prefer to have many specific goals so we can all find a home.
- Geneve: Is anyone performing objective 1 any more?
- McGrath: Not since TeKrony retired.
- Duggan: Why not determine the effect of the environment on seed quality?

General consensus

- Bradford: The third and last point would be technological aspects of seed quality.
- Geneve: Those speaking at the symposium on delivering a commodity through the seed are not represented in our W-1168 objectives.
- Nonogaki: Seed business focus. We have no one working on nutritional aspects/ecological aspects, so if we decide to include this as emphasis, we need to obtain these people.
- Cohn: Now is not the time to do the rewrites on new topics. We need to cultivate new members now with an eye to expanding our objectives.
- Bradford: We probably won't be able to attract these type of people.
- Welbaum: The people invited into the seminar are not experiment station people.
- Bradford: If we go to a more impact oriented set of goals, what are we going to say?
- McGrath: I prefer the more general objectives.
- Geneve: The group has changed over the last few years.
- Nonogaki: One strength of our group is that both the basic and applied expertise exists in our group.
- McDonald: We are moving away from research on seeds as a propagule. This will influence this group.
- Bradford: Gene switching should be the seed biologists' turf.
- McGrath: Integrative Seed Biology or Seed Systems Biology.
- Welbaum: Like the first. Buzzwords plus whatever you want it to be.
- McDonald: The weeds people have all become seed ecologists. There may be many researchers out there working with seeds that feel that they do not have a home.
- Duggan: Pre- and Post-Harvest Issues, Establishment Ecology, Nutritional and Value Added.
- Bradford: Targeting the propagule issues that come with the third objective.
- Geneve: Two levels. The renewal is a paperwork issue and is not the time to be creative. The second level is progressive alteration of the direction for the next iteration.
- Steber: Victor Rayboy. Phytic acid.
- McDonald: You must ask how are we going to remain relevant.
- Welbaum: Educational aspect is another emphasis of this group.
- Geneve: That isn't research which is the USDA mandate for the meeting.
- Bradford/McDonald: Agree with Geneve.
- McGrath: For the rewrite we need to request permission to submit a
rewrite. The group is going from altering the seed to improve a crop or produce it better to altering the propagule so that it doesn't do something that it was doing or to get it to do something that it otherwise wouldn't.

General questions
- Do we have a stakeholder group? Restoration.
- How specific do we have to be?
- Food and biotechnology industries.
- Biofuels

- Cohn: We have to stay with our strengths and slowly extend tentacles to others in this area. However, use the buzzwords in our introduction and discussion and say that what we do is the bedrock of what all these endeavors are based on.
- McGrath: Will do a draft of our request to submit and then send this out to the group.
- Bradford: You need a committee to help you.
- McGrath: We have 15 minutes to come up with a title and three objectives.

Official objectives for the W-1168 re-write:

- Pre- and Post-Harvest Issues.
Pre- and post-harvest issues of the environment.

- Establishment Ecology.
Seed ecology and stand establishment.
Seed ecology and population establishment.

- Nutritional and Value Added.
Seed quality, genetics and technology.
Seed dormancy, germination and after-ripening.


BREAK
Reconvene 2:00 p.m.

10: State Reports.

Steber: USDA-ARS, Washington State Univ., Pullman, WA.
The Role of the GA Signaling SLY1 in Arabidopsis Seed Germination.

Welbaum: Virginia Tech, Blacksburg, VA.
An Overview of Seed Research at Virginia Tech.

Allen: Brigham Young University and Susan E. Meyer, USDA Forest Service Shrub Sciences Laboratory. The Big Model: Linking the Dormancy Loss with the Hydrothermal Time Model.

Nonogaki: Oregon State University, Corvallis, OR.
Integrative Seed Biology.

McDonald: The Ohio State University, Columbus, Ohio.
Written presentation.

Taylor/Yuliya Salanenka: Cornell University, Geneva, NY.
Seed Coat Permeability and Uptake of Applied Systemic Compounds.

Cohn: University of Louisiana, Baton Rouge, LA.
Possible Targets for Damage. Is the Cause of Damage Physical and/or Chemical?

END OF THE DAY

Off for supper.

SUNDAY, December 3, 2006.
Continuation of the State Reports.

Norcini: University of Florida.
Coreopsis Lancelolata and Floridana Seeds.

Leskovar: Texas A&M.
High Temperature Stress Under Deficit Irrigation on Poblano and Bell Pepper.

Downie: University of Kentucky, Lexington, KY.

Geneve: University of Kentucky, Lexington, KY.
The Relationship Between Ethylene Production and Dormancy Release in Echinacea Seeds.

McGrath: Thanks Daniel for an excellent meeting. This was also reiterated by Miller for the whole group to Daniel.

Continuation of state reports:

Bradford, University of California, Davis, CA; Peggy Lemaux and Bob Buchanan, UC Berkeley.

Interruption of state reports due to need to decide on rewrite themes.

The consensus objectives of the rewrite for the W-1168 proposal are to:

1. Identify biophysical, biochemical, genetic and environmental factors associated with seed development, germination, vigor and dormancy.

2. Determine the influence of environmental factors on emergence and population establishment in natural and agro-ecological settings.

3. Develop technologies to assess and improve seed quality, improve seed performance, and enhance seed utilization.

Volunteers for drafting the rewrite?

Bradford and Steber can help on the first objective.
Allen can help with the second objective.
Geneve and McDonald can help on the third objective.

Discussion
- Alan Taylor suggested a conference call with Paul Rasmussen to hammer out what we should focus on now that the playing field has changed.
- Geneve: Stakeholder input should be solicited.
- McGrath: Will start a request for renewal and send it out to members for comments as well as to Paul. Next phase will be to flesh things out under each subheading. Interactive process. Aim next Sept. for a working draft.
- Bradford: At the Sept. meeting we might reduce the state reports and spend time on fine tuning the report. Preferences on the timing of the meeting?

Consensus: Travel Saturday, meet Sunday, finalize Monday.

- Geneve: Because all will be staying for the meeting, we can have Monday afternoon as a safeguard.
- Bradford: Allot time for collaborative discussions.
- Taylor: Should send our request for renewal to Liang-Shiou Lin as well?

General Consensus.

- Cohn: We need our admin. guys on our side.

Continuation of State Reports:

McGrath, USDA, Michigan State University, East Lansing, MI

End State Reports.

McGrath concluded the meeting @ 11:20 a.m.

Accomplishments

Objective 1. Pre-harvest stress and seed quality.<br /> <br /> Establishing the timing of maize male inflorescence is critical to understanding the effects of stress on tassel development and pollen production. Critical events of tassel and pollen formation were characterized. Tassel was initiated from fourth leaf stage, six leaf tips (V4:T6) to V5:T7. Branch meristems appeared from V4:T7 to V6:T9. Spikelet-pair primordia appeared from V5:T7 to V7:T10, while sessile spikelets differentiated from V5:T9 to V8:T12. Lower florets were initiatied from V6:T11 to V8:T13. However, lower florets were initiated within a 60 heat unit period across the tassel. For a given spikelet-pair, florets formed in the pedicellate spikelet only slightly prior to the sessile spikelet. Anthers were visible within 30 heat units of floret development. Pollen cells entered meiosis approximately 90 heat units after anther initiation, and pollen meiosis occurred from V9:T14 to V12:T15. (IA)<br /> <br /> Effects of water availability during seed development in lettuce (Lactuca sativa) were investigated. Seeds of cv. Tango were produced in a greenhouse under one of two treatments: i) wet (watering volume equivalent to evapotranspirated volume), and ii) dry (watering volume ~ 54% of wet treatment). The dry treatment produced significantly shorter plants with fewer but heavier seeds. Without light, at 20°C, seed germination from both treatments was reduced drastically, with a significant difference in favor of the dry treatment. In both treatments germination decreased at increased levels of exogenous ABA concentration, however seeds from the dry treatments were more sensitive to ABA. The results indicated that water availability during seed development not only affected seed yield and weight, but also germinability under sub-optimal conditions. (OH) <br /> <br /> Day-length during seed development affects germinability and storability of lettuce seeds. Seeds of cv. Tango were produced in growth chambers under i) short day (SD): 8 h of fluorescent light (~310 mmol m-2 s-1) plus 16 h of darkness or ii) long day (LD): 8 h of fluorescent light plus 8 h of incandescent light (~21 mmol m-2 s-1) and 8 h of darkness. In both treatments the temperature was 23°C, constant. The LD treatment produced significantly heavier seeds. At suboptimal conditions (30°C or 20°C with different external ABA concentrations), seeds from SD treatment exceeded seeds from LD in both germination percentage (GP) and germination index (GI). When germinated in dark at 14, 19, and 24°C, GP was significantly higher for seeds from SD; seeds from both treatments presented no germination at 29°C in dark. After accelerated aging (41°C, ~100%RH, 72 h) GP was higher for seeds from LD. Seed germination was also evaluated after 2, 4, and 6 months of storage at i) 30°C, 55% RH and ii) 30°C, 74% RH. Seeds stored at 74% RH presented a significant reduction of GP and GI for both treatments, however seeds from SD were more affected. The results indicated that day-length during seed development affected lettuce seed weight, germinability, and storability. (OH)<br /> <br /> Effects of temperature during seed development were analyzed. Seeds of lettuce cv. Tango and Helianthus debilis cv. Vanilla Ice and ssp. Cucumerifolius were produced in greenhouse under i) hot (27, 40, and 20°C temperatures average, max, and min respectively), and ii) cool (23, 33, and 18°C temperatures average, max, and min respectively) conditions. In both species heavier seeds were produced under the cool conditions. In lettuce, germination was affected by increased levels of exogenous ABA and by reduced water potential, and in both cases seeds from cool treatments were more affected. In lettuce, germination at 30°C and constant light was higher for seeds from the hot treatment. Lettuce seed showed a strong light requirement for germination, which varied with the temperature. Seeds from the hot treatment presented better dark germination at 13 and 19°C. Seeds from H. debilis did not require light for germination, and the germination percentage and rates were evaluated at 13, 21, and 29°C. The germination at 29°C of H. debilis cv. Vanilla Ice was higher when seeds were produced under the hot conditions. The results showed that temperature during seed development affected seed quality that is not distinguishable by the standard germination. (OH)<br /> <br /> Little is known about the optimum time of harvest for best orchid seed quality. Flowers of Phalaenopsis amabilis were self-pollinated twice. Pods were harvested at 90, 105 and 120 days after pollination (DAP). Seed size, cell form, and color were determined at each harvest date. Seeds were tested for initial viability and stored under different temperature and moisture conditions. 90 DAP seeds stained positive with tetrazolium (TZ) but did not germinate. Results at 105 and 120 DAP were similar with 120 DAP demonstrating greater vigor by developing protocorms. Seeds were largest and had the greatest embryo cell number at 120 DAP. Embryo staining with TZ was not a good predictor of orchid seed germinability and should not replace seed grow outs. (VA) <br /> <br /> Objective 2. Biophysical, biochemical and genetic factors in seed desiccation tolerance and longevity.<br /> <br /> Model system Spartina alterniflora for a desiccation tolerance study was developed. The importance of comparative physiological approach to studying seed death due to drying (recalcitrance) was validated by parallel experiments with the recalcitrant S. alterniflora and the orthodox S. pectinata. The critical moisture content of recalcitrant alterniflora seeds was identical for both dormant and non-dormant seeds. The contribution of peroxidative reactions to recalcitrant seed death was evaluated. Ferric orange-xylenol (FOX) reactive substances increased only in non-dormant alterniflora during drying; there was no increase in FOX-positive substances in dormant alterniflora. However, the total antioxidant titer decreased in alterniflora, and this decrease was associated with a substantial increase in protein oxidation during drying. (LA)<br /> <br /> DGMI is a digalactosyl derivative of myo-inositol, a member of the Galactinol series of cyclitol galactosides, and a minor component in soluble carbohydrates from buckwheat (Fagopyrum esculentum) seeds. DGMI was purified from seeds of buckwheat using combinations of solvent extraction and fractionation of extracts on ion-exchange columns and carbon-Celite columns. DGMI was purified by repeated chromatography on carbon-Celite columns. The presence of myo-inositol, galactinol, and DGMI in seed extracts were tentatively identified by gas chromatography. Acid (2 N trifluoracetic acid) hydrolysis of galactinol resulted in galactose and myo-inositol in the mole ratio 1.03:1.00. Acid hydrolysis of DGMI resulted in galactose and myo-inositol in the mole ratio 2.08:1.00; upon partial hydrolysis of DGMI, galactinol, galactobiose, galactose, and myo-inositol were detected. Galactinol and DGMI were hydrolyzed by a-D-galactosidase from green coffee bean, but not by b-D-galactosidase, identifying a-galactoside linkages. The absolute configuration of DGMI was determined by 1H-NMR, 13C-NMR and two-dimensional NMR. All galactosyl linkages were confirmed to be a-anomeric. The proximal galactosyl linkage was to the 1L-carbon of myo-inositol. The NMR spectra and hydrolysis confirmed the structure of DGMI to be a-D-galactopyranosyl-(1-6)-a-D-galactopyranosyl-(1-1)-1L-myo-inositol. (NY)<br /> <br /> Seed conservation is an important undertaking to ensure preservation of plant biodiversity. Effective conservation of seeds depends on the storage temperature and seed moisture content. Maintaining genebanks is expensive especially in many parts of the world where the cost of cold storage is prohibitive. The ultra-dry technology was proposed as an alternative method. Its effect on the seedling vigor must be evaluated. Seeds of lettuce cv. Tango were dried using two methods. The first was rapid drying conducted with PVC tubes with computer-controlled fan and the tube placed inside a glass desiccator with activated desiccant and drying was done for 4-10 d. The second method was performed by drying seeds over activated desiccant for 30 d and seeds sampled every 5 d. Seed moisture content (MC) measurement and germination tests were conducted following the standard protocol and the seedling vigor was assessed using the OSU Seedling Vigor Imaging System (SVIS). Rapid drying of seeds decreased the MC from 6 to 0.93% in 4 d. Drying seeds for 10 d resulted in 0.32% MC. Germination was only slightly affected by the decrease in MC. Germination at 6% MC was 100% and when dried to 0.32% MC germination decreased to 97%. Drying seeds for 5 d decreased the MC from 6 to 2% and further drying for 30 d resulted in 0.8% MC and germination only decreased from 100 to 98%. The results showed that germinability was only slightly affected by extreme reduction in MC. Germinability and desiccation tolerance are important attributes that seeds acquire during development. It is important to better understand how different environmental conditions affecting the mother plant influence seed quality. Lettuce cv. "Tango" was cultivated in the greenhouse. Seed germination, under light and darkness was evaluated in fresh and dry seeds at 3, 5, 7, 9, 11, 13, 15, and 17 days after flowering (DAF). Seed fresh and dry weights were monitored. Desiccation was performed ~1 h after harvest by placing the seeds over a sodium bromide solution (~53% RH) at 25°C. MC decreased from ~14% 3 DAF to ~7% 7 DAF and then remained constant. Seeds achieved maximum dry weight ~13 DAF. Germination of fresh seeds increased from 0 to ~80%, reaching a maximum (100%) germination 7 DAF. Dry seeds did not germinate when they were harvested 3-5 DAF. Seeds harvested at 7 DAF had ~10% germination and at 9 DAF, germination was ~100%. When germinated in the dark, an increase in germination from 0% in fresh seeds at 3 DAF to 50% germination at 5 DAF was observed. However, seeds at 9 DAF had dark germination that decreased to 0% and increased again to ~70% germination at 13 DAF. Dry seeds had no dark germination until 7 DAF, with variable and low germination (below 20%) until 11 DAF, then germination reached a maximum of ~55% 13 DAF and decreased to a minimum below 10% 17 DAF. Thus, lettuce seed germinability and desiccation tolerance were reached sooner than physiological maturity. (OH)<br /> <br /> Orchid germplasm preservation is important because some species are endangered due to loss of habitat and human predation. Very few of the world's genebanks are involved in orchid preservation. Orchid germplasm preservation is a mission of the USDA Ornamental Plant Germplasm Center in Columbus, Ohio. Brassia and Phalaenopsis seeds were harvested at different stages of development and stored at -196 °C (liquid nitrogen), -80 °C, -18 °C, 4 °C and 25°C for 6, 12, 18 and 24 months. Phalaenopsis and Brassia seeds adjusted to 45.5% RH over chromium dichromate were able to survive short-term storage (10 d) at all temperatures. Seeds frozen in liquid nitrogen for 30 min were able to germinate and produce protocorms 19 d after sowing, just a day longer than control seeds. Liquid nitrogen storage improved germination of some Phalaenopsis seed lots from 0 to 38%. Storing Phalaenopsis seeds at -80 °C and 4 °C also improved germination, suggesting dormancy was broken by low temperature. Orchid seeds tolerate freezing in liquid nitrogen and cryropreservation may be a viable long-term strategy for orchid germplasm preservation . (VA)<br /> <br /> Objective 3. Genes associated with seed development, germination, vigor and dormancy.<br /> <br /> Two lettuce populations are evaluated to identify genetic determinants of seed dormancy and quality. Major QTL have been identified in both populations for high temperature germination (Htg). In a recombinant inbred line (RIL) population derived from a cross between L. sativa cv. Salinas and L. serriola (UC96US23), a major QTL on linkage group 6 (Htg6.1) has been introgressed into the Salinas background (BC2S1) and the phenotypic effect of the locus has been confirmed in segregating progeny. Gene expression studies indicate that inhibition of GA synthesis and promotion of ABA synthesis are associated with the tolerance of high temperatures associated with Htg6.1. A second major QTL has been identified on linkage group 9 (Htg9.1) in a RIL population derived from a cross between L. sativa cv. Salinas and a L. sativa landrace (PI251246). (CA)<br /> <br /> Two maize hybrids, B73 x IRF311 and Mo17 x IRF311, were produced. During seed maturation, ears were harvested at 500-550, 400-450, and 300-350 g kg-1 MC with the husks intact. All ears were placed in 10°C for 2 h to ensure similar freezing rates. Control ears were husked and dried immediately. The frost treated ears were placed in a growth chamber for a 24 h freeze cycle. After the artificial frost cycle, ears were dried in experimental driers with unheated air and shelled. Differential expression of mRNA between frosted and non-frosted seed is being analyzed. (IA)<br /> <br /> Map based cloning of tomato brownseed1 (bs1) mutant has been continued. 535 recombinants were identified within 17 cM of bs1 (between morphological markers irr and au, situated on either side of bs1) and sequenced and 200,000 contiguous bases from two BACs centered on this region were assembled. The sequence has been used to develop SSLP, CAPS, and dCAPS markers between L. esculentum and L. pimpinellifolium between irr and au. (KY)<br /> <br /> AGL15, a MADS-box gene can promote somatic embryogenesis (SE) in two systems. The effect of loss-of-function alleles of AGL15 was tested in these systems. The loss of AGL15, and in one system the potentially redundant function AGL18, were found to decrease the ability of explants to undergo SE. Auxin treatment, important for SE, leads to increased expression of AGL15. Two AGL15 target genes with roles in SE have been identified. A better understanding of the developmental mechanisms controlling SE will aid regeneration of recalcitrant species in culture. Work supported by the USDA-NRI is testing whether GmAGL15 can enhance SE in soybean and preliminary results look promising. SE serves as a more accessible model for zygotic processes, but little is understood about mechanisms involved in promoting dedifferentiation and redifferentiation as tissue with embryo identity. The Perry lab seeks to better understand this process by identifying and characterizing genes directly regulated by AGL15. A chromatin immunoprecipitation (ChIP) approach was successfully used for identification of genes regulated by AGL15. Because some genes are directly repressed by AGL15, it is likely that AGL15 interacts with other proteins to control gene expression. A yeast 2-hybrid approach indicated that AGL15 may interact with components of histone deacetylase complexes to control gene expression. Other work using a transient expression system has demonstrated that different domains within AGL15 may be responsible for activation or repression of gene expression. (KY)<br /> <br /> Over 3,000 EST from sugar beet seedlings were obtained and deposited in GenBank. For ca. 75% of the sequences, putative function assignments encompassed a wide range of biological roles and molecular functions. Each of four classes of EST sets constructed with different methods had different numbers of ESTs, and the proportion of ESTs with a particular biological role was compared between libraries. For metabolism biological role, the proportion of ESTs in each set was comparable, suggesting that differential display, subtracted, and random sequencing approaches lead to similar conclusions. The differential display approach seemed to provide the best enrichment scheme for Stress Response, Cell Wall & Cytoskeleton, and Transport processes, suggesting these processes may yield more clues as to the nature of stress responses during germination. Fewer ESTs with an unknown function were seen in the random cDNA sequencing set than the others, suggesting one function of directed or subtraction strategies is to add complexity to the nucleotide sequence dataset, which in this case was desired. The de-emphasized biological roles appeared to relate to protein synthesis, modification, and turnover (e.g. processes affecting protein homeostasis), signaling, and transcription, since these were more frequently detected in the un-selected transcript pool. Molecular functions were ascribed to each EST, and examined as a proportion of the total number of ESTs or as a proportion of their putative biological roles. Stress responsive ESTs and ESTs whose predicted gene functions are in central one carbon metabolism were highly represented. Subdivision of biological roles and molecular functions relative to their respective EST sets revealed differences in the proportion of ESTs from each set, for some molecular functions. For instance, cytoskeleton- and membrane-destined transcripts appeared to be enriched with cDNA subtraction, where histones appeared to be underrepresented. Little or no change in the relative proportion of transcripts assigned to EST sets was evident for 17 of the 36 molecular functions assigned here. Similar numbers of molecular function-assigned transcripts were enriched in the subtracted versus un-subtracted EST sets as were depleted, and these transcripts would be expected to over- and under-represented, respectively, in the un-subtracted cDNA library. Such differences may point to potentially important functions operating to counter stress during germination. (MI)<br /> <br /> A PWWP transcription factor was identified from the Seed-GUS-Expressed enhancer-trap lines. The PWWP gene is expressed in the cotyledon tips of embryos in imbibed seed while they are still enclosed by the endosperm and testa. At postgerminative stages, hydathodes of rosette and cauline leaves exhibited PWWP expression. Functional analyses have indicated that the PWWP knockout mutant seeds have reduced sensitivity to ABA. Results from gene expression analyses suggest that auxin sensitivity is also altered in the mutant seeds. (OR)<br /> <br /> To understand the biological roles of the transcription factors in seeds potentially regulated by miRNAs, vectors that cause de-regulation of the target genes from miRNAs were prepared and Arabidopsis plants were transformed with these vectors. Preliminary data showed that some of these miRNA de-regulation plants exhibited overaccumulation of the transcription factors and interesting phenotypes. One of the most prominent phenotypes was hypersensitivity of seeds to ABA. (OR)<br /> <br /> Red rice seeds have been used for studying the mechanisms of seed dormancy. Taking advantage of the fully sequenced genome of cultivated rice, microarray studies were done in collaboration with Dr. Marc Cohn to compare global gene expression changes in dormant red rice seeds and red rice seeds whose dormancy were broken with NOX treatment. (TN)<br /> <br /> All mannanase genes in Arabidopsis, rice and poplar were compared. Phylogenetic relationships of these genes were analyzed. The expression of the individual Arabidopsis and rice mannanase genes in various tissues including germinating seeds were examined. (TN)<br /> <br /> In tomato and Arabidopsis, GA is required for seed germination. GA stimulates germination by triggering destruction of DELLA via the SCF-SLY1 E3 ubiquitin ligase and the 26S proteosome pathway. DELLAs are negative regulators of GA responses, and RGL2 is the main DELLA repressing seed germination. SLY1 appears to tranduce the GA signal by triggering DELLA destruction by ubiquitination. GA-insensitive sly1 mutants resemble GA biosynthesis mutants in that they exhibit dwarfism, late flowering, reduced fertility and increased seed dormancy. These sly1 phenotypes are not rescued by GA and are not as severe as those seen in the ga1-3 GA biosynthesis mutant. While ga1-3 seeds fail to germinate in the absence of GA, the seed germination rate varies greatly (3-100%) among independent seed lots of young sly1 mutants. Dormant sly1 seeds eventually afterripen. However even sly1 seeds that can germinate do so more slowly than WT and show greater sensitivity to ABA and reduced osmotic potential. The germination of dormant sly1 seeds improved following afterripening. We examined the effect of these mutations on RGL2 accumulation. It is known that high levels of RGL2 in the ga1-3 correlates with failure to germinate, and that mutations in RGL2 suppress the ga1-3 germination phenotype. sly1 seeds are able to germinate even when high levels of RGL2 are present. This suggests that protein disappearance may not be the only mechanism controlling RGL2 activity. (WA).<br /> <br /> Objective 4. Technologies to assess seed quality, improve seed performance and enhance seed.<br /> <br /> Studies on seed quality and longevity often use controlled deterioration (CD) to assess the longevity of seed lots. These tests assume that aging rates under CD conditions (e.g., 75% RH and 50°C) are correlated with aging rates under more optimal storage conditions (e.g., 30% RH and <20°C). We tested this assumption using a RIL population developed from a cross between L. sativa cv. Salinas and L. serriola (UC96US23). Viability of a given line after 2 years of aging at 30% RH and 20-30°C was poorly correlated with viability after CD at 75% RH and 50°C or at 50% RH and 60°C. Nonetheless, one QTL was identified associated with seed longevity under all conditions, and additional QTL were associated only with either natural or CD aging conditions. (CA)<br /> <br /> A population-based threshold model was applied to quantify the responses of germination to oxygen availability. The model accounted well for germination responses to reduced oxygen partial pressures and provided quantitative measures of oxygen sensitivity among species and dormancy states. (CA)<br /> <br /> A new instrument to measure oxygen consumption of individual seeds in 96-wells (Q2, www.astecglobal.net) was evaluated as a seed vigor test. Seed lots representing diverse quality levels and enhancement treatments were assessed in the instrument and feedback was provided to the manufacturer on how to improve its operation. (CA) <br /> <br /> The requirements for and results from priming lettuce seed can vary according to age, vigor, and thermosensitivity of the seed. Optimal hydrothermal timing was determined for priming lettuce seeds, independent of cultivar, seed lot, and storage using an inexpensive gel assay for the enzyme endo-b-mannnanase (EBM). Two lettuce cultivars 'Bennett' and 'Connick' and two seed lots of each were used. The seeds were primed in an aerated 1.2 MPa polyethylene glycol 8000 solution at 15°C in constant light, and were sampled at 24, 48, or 72 h. A single-seed assay for EBM was used to determine enzyme activity for each lot at each priming duration. At 36°C, germination of primed seeds was over 90%, while non-primed seeds germinated at 40%. EBM activity was non-detectable in dry seeds and for less than 5% of the seeds primed for 24 h. After priming for 48 or 72 h, 30% or more of the micropylar section of the seed exhibited EBM activity, regardless of seed lot or cultivar. Since the percentage of seeds exhibiting EBM in the whole endosperm after 48 or 72 h of priming were similar, but total percent and rate of germination at 36°C were optimal at 48 h prime duration, 48 h was considered the optimal hydrothermal priming time. EBM activity was observed in 25% of seeds at 48 h priming duration. Therefore, it was proposed if at least 25% of seeds exhibited EBM activity, optimal hydrothermal time is achieved. Cost analysis of the EBM test was determined to cost $11.56 per 1000 seeds. This price does not include facilities or equipment costs. Determining priming time with the EBM test provides a method to improve optimization of the priming procedure. (FL)<br /> <br /> In lettuce cultivars, temperatures above 30°C can inhibit germination completely. Lettuce seeds imbibed at supraoptimal temperature for 72 h or more will not germinate even when the temperature is returned to the optimal range. Thermosensitive 'Dark Green Boston' and thermotolerant 'Everglades' respond to temperature at seed maturation by being able to show greatly enhanced germination at 36°C when seeds were matured at 30/20°C. ABA may contribute to lettuce seed thermodormancy. Therefore, sensitivity of 'Everglades' and 'Dark Green Boston' to ABA of seeds maturated at 30/20°C and 20/10°C in light and dark was determined. At 36°C in dark, both genotypes matured at 30/20°C germinated more than those matured at 20/10°C. 'Dark Green Boston' was more sensitive to ABA at 36°C in dark. When ABA was added, those seeds matured at 30/20°C germinated better than those matured at 20/10°C regardless of genotype. At 36°C in light, 40% of both genotypes were inhibited at 0.5 ¼M ABA. At 36°C in dark, germination of all seeds but 'Everglades' matured at 30/20°C were completely inhibited with all ABA concentrations. Thus, seed maturation temperature has an influence on lettuce seed germination at high temperature and sensitivity to ABA. (FL)<br /> <br /> Collaborations with seed biologists in India, Australia, China, and Taiwan were conducted to better determine the class of dormancy in various species and how it is broken in nature. Further, a large project on species growing in the montane zone in Hawaii was continued. Research was done on seeds from China, Taiwan, Australia, Hawaii, and eastern North America. Studies on various aspects of physical dormancy in seeds paying particular attention to ecological and evolutionary aspects was done by graduate students. (KY)<br /> <br /> Seed dormancy release treatments were developed for three wild rye (Elymus) species. A method to record repeated digital images of germinating seeds using a flat bed scanner was developed. This method was used to dynamically study imbibition in seeds with physical dormancy. (KY)<br /> <br /> Organic solvent infusion for permeation of signal transduction inhibitors in red rice caryopsis was optimized. Neat demethylsulfoxide (DMSO), methanol and ethanol were either toxic or broke dormancy when applied for 1-24 h. Neat acetone infusion for 24 h did not kill the seeds or break dormancy. DMSO inhibited the dormancy-breaking activity of propanol; this was consistent with the alcohol dehydrogenase-inhibiting property of DMSO. (LA)<br /> <br /> Sugar beet growers in the Great Lakes region and worldwide are consistently faced with problems of poor stand establishment. Part of the reason can be differences among varieties in their ability to overcome environmental stress. A laboratory stress germination test was developed which predicts the relative field emergence potential. Field emergence has been 60% of that predicted by standard germination tests in average years. Although emergence does not seem to affect yield measured in tons per unit area, it does impact the sugar yield per unit area due to uniformity in plant spacing, and results in an increase in overall quality and quantity of sucrose recovered. This research will enhance understanding of stress response in sugar beet and allow for selection of germplasm tolerant to some of the abiotic and biotic stresses. (MI)<br /> <br /> Two beet germplasms were released. A table beet germplasm, TBEL1, was selected for cylindrical shape and moderate sucrose content. TBEL1 was derived from an experimental hybrid between sugar beet and table beet. It is expected TBEL1 will be a source for development of new varieties of red table beets for canning, where the cylindrical shape results in less waste during the canning process compared with the standard globe beet shape, and better consumer acceptance due to higher sucrose content than available cylindrical beet types. EL53 sugarbeet germplasm was released. It is substantially derived from previously released smooth-rooted, low soil tare germplasm releases with two cycles of selection for freedom from crown and root rot disease caused by Rhizoctonia solani Kühn (AG2-2). Previous low soil tare releases have been uniformly susceptible to Rhizoctonia crown and root rot. (MI)<br /> <br /> A laboratory stress germination test was developed for sugar beet, whereby the ratio of seeds germinated in water to the number germinated in hydrogen peroxide was shown to reflect a quantity defined as the Field Emergence Potential. This test appears to predict the genetic component of seedling vigor, but also demonstrates differences between seed lots of the same variety. Selection and breeding for enhanced vigor were initiated in 2006. 176 accessions were tested for salt-stressed seed germination, and ca. 50% of cultivated and 80% of wild accessions showed a non-zero FEP. Germinated seeds from accessions with the highest FEP were planted, vernalized and allowed to flower in isolation from one another for seed production. Segregation for FEP was observed among the progeny, with mean FEP of the progeny improved by as much as 150% of the parental material. (MI)<br /> <br /> Film coating is one technology that results in a uniform deposition of a thin film on the seed surface and reduces worker exposure to seed treatments. The efficacy of systemic seed treatments depends on the ability of applied chemical compounds to penetrate the seed coat and be transported into the seedling. Fluorescent tracers were employed to mimic movement of seed treatments and for visualization of chemical movement. Fluorescent tracers were applied to seeds by a dry powder coating, placed in moistened sand for 18-24 h at 20°C and removed prior to germination events. Imbibed seeds were hand dissected and the location and intensity of fluorescence was observed under long-wavelength UV light. Large-seeded legumes have permeable seeds coats to fluorescent tracers. Cucurbit and lettuce seed coats were impermeable to fluorescent tracers supporting the hypothesis of an 'endosperm envelope' surrounding the embryo. Tomato, pepper, onion and leek have selective permeable seed coats, and uptake was dependent on the chemical nature of the fluorescent tracer. (NY)<br /> <br /> An image processing computer application was developed to collect statistics from seeds. A machine learning technique ensured the software was applicable to a wide variety of species so the software could be used in purity analysis tests. The method requires an inexpensive scanner and a modern personal computer. The software operates by locating seeds within the digitized image of the purity sample and takes measurements on each seed. These measurements are inputted into a classification routine trained to recognize all potential seeds within the sample. The classification routine determines the closest matching species for each seed in the image and reports the results to the user. The seed identification system is designed to be rapidly adapted to specific seed types and trained without knowledge of artificial intelligence techniques. Reliable and fast results from seed quality tests are essential for producers. (OH)<br /> <br /> The SVIS was developed to improve seed quality assessment. This study had the objective of identifying the optimum MC for paper towels used in germination testing as well as the desired temperatures for germination during the three-days of test. Seeds were planted in paper towels with seven different MC for maize and eight for soybean. Three different temperatures (24, 25, AND 26C) were used for germination of the two crops. Decreased speed of growth and overall vigor indices were observed when the MC of the paper towel was less than 96% saturation in maize and 79% saturation in soybean. When the germinator temperature varied 1C less than 25C, no difference in SVIS indices was detected. However, a difference of 1C more than 25C caused a significant difference in seedling growth. These results demonstrate the importance of monitoring MC in paper towels, particularly for maize seeds, used in the conduct of the SVIS test and show that moisture and temperature variables must be carefully monitored during the conduct of standard germination and vigor tests to assure standardization of reported results. (OH)<br /> <br /> High air temperatures with dry winds and rapid soil drying conditions encountered in many southern regions of the U.S. can reduce stand establishment of transplants. Understanding the physiological characteristics that moderate transplant shock can provide a basis for elucidating the mechanisms underlying transplant stress tolerance. We investigated the influence of physiological compounds (ABA and aminoethoxyvinylglycine, AVG) and physical (AntiStress, Transfilm and Vapor Gard) antitranspirants on the growth of pepper and artichoke seedlings exposed to desiccation. In pepper, root application of ABA enhanced desiccation tolerance compared to foliar application. Leaf photosynthesis and conductance decreased upon ABA foliar application; however, photosynthesis rates recovered within a few days of application. Throughout two cycles of desiccation on pepper seedlings, ABA had a stronger effect in reducing stomatal conductance and photosynthesis while increasing leaf and stem water potential compared to AVG or physical antitranspirants. Most transplant growth changed at the shoot level, and the control of shoot growth by ABA appeared to be transient. Similar trends were measured for artichoke. (TX) <br /> <br /> We evaluated the effect of ABA applied as foliar spray for 5, 10 or 15 consecutive days on pepper transplant. ABA at 0.1 mM had a slightly positive effect on net photosynthetic rate after 5 or 10 d of continuous application, but negative after 15 d. Transplants exposed to 1.0 mM ABA for 5 or 15 d had reduced photosynthetic rate and stomatal conductance. Leaf xylem water potential increased and stem elongation decreased with ABA after 10 or 15 d of continuous application. Shoot weight and leaf area were maintained with ABA at 0.1 mM, irrespective of exposure time, but with 1.0 mM ABA growth was lower compared to control. Root weight was less affected than shoot weight, leading to increased root to shoot ratio. Application of 1.0 mM ABA for 5 or 15 d enhanced total and specific root length. (TX) <br /> <br /> Controlling height of bedding plants enables successful marketing. Compact vegetable transplants establish easier with less shock and produce more productive mature plants. Chemical growth inhibitors are commonly used to maintain bedding plant height. However, some chemical inhibitors have a long lasting effect that may not be easily overcome after transplanting. Natural solutions are needed for controlling plant height for organic markets. The use of controlled osmotic stress was investigated to control the growth of tomato and kale (Brassica oleracea Acephala Group). Tomato and kale responded differently to osmotic stress with kale being more sensitive to osmotic stress with more leaf yellowing. Beeswax/potassium sorbate showed potential as a natural plant growth retardant that produced less yellowing than sugar treatments. PEG applied post-germination and some sugar treatments stimulated plant growth rather than retard it. This could be due to stimulation of soil-borne growth promoting plant microbes. Sunshine soilless media, feed sucrose or trehalose produced microbial biofilm that increased media moisture retention characteristics. (VA)<br />

Publications

Baskin, J.M., C.C. Baskin, C.-T. Chien and S.-Y. Chen. 2006. Seed dormancy in the early diverging eudicot Trochodendron aralioides (Trochodendraceae). Seed Sci. Res. 16: 71-7<br /> <br /> Baskin, J.M., C.C. Baskin and K.W. Dixon. 2006. Physical dormancy in the endemic Australian genus Stylobasium, a first report for the family Surianaceae (Fabales). Seed Sci. Res. 16: 229-232.<br /> <br /> Baskin, J.M., S.N. Hidayati, C.C. Baskin, J.L. Walck, Z.-Y. Huang and C.-T. Chien. 2006. Evolutionary considerations of presence of both morphophysiological and physiological seed dormancy in the highly-advanced euasterids II order Dipsacales. Seed Sci. Res. 16: 233-242<br /> <br /> Baskin, C.C., K. Thompson and J.M. Baskin. 2006. Mistakes in germination ecology and how to avoid them. Seed. Sci. Res. 16: 165-168.<br /> <br /> Bonina, J.R. and D.J. Cantliffe. 2006. A rapid, simple, inexpensive and reproducible endo-beta-mannanase assay test for determining optimal hydrothermal timing of commercial priming of lettuce seed. J. Seed Tech. In Press.<br /> <br /> Bradford, K.J. 2006. Seed biotechnology: Translating promise into practice. In S. Navie, S. Adkins, and S. Ashmore, eds., Seeds: Biology, Development and Ecology, CAB International, Wallingford, U.K., pp. 130-138.<br /> <br /> Bradford, K.J. 2006. Germination: internal factors affecting (physical, physiological, molecular and biochemical). In Bewley, J.D., Black, M., and Halmer, P., eds., The Encyclopedia of Seeds: Science, Technology and Uses. CABI Publishing, Wallingford, UK. <br /> <br /> Bradford, K.J. 2006. Methods to maintain genetic purity of seed stocks. University of California, Division of Agriculture and Natural Resources, Publication 8189. http://anrcatalog.ucdavis.edu.<br /> <br /> Bradford, K.J., J. Argyris, P. Dahal, P. and L. O'Brien. 2006. Genetics, regulation and modeling of seed dormancy. Abstracts, 26th Annual Meeting of the Argentine Society of Plant Biologists, Chascomus, Argentina, October 4-6, 2006.<br /> <br /> Bradford, K.J., J. Argyris, P. Dahal, L. O'Brien, M.J. Truco, O. Ochoa, D.W. Still, R. Grube, R. Hayes and R.W. Michelmore. 2006. Genetic analysis of lettuce seed thermodormancy. International Society for Horticultural Science: 4th International Symposium on Seed, Transplant and Stand Establishment of Horticultural Crops, Dec. 3-6, 2006, San Antonio, Texas.<br /> <br /> Brancalion, P.H., D. Tay, R.R. Rodrigues and A.D. Novembre. 2006. Priming of Guava Seed (Psidium guajava L.). 27th International Horticultural Congress, August 13-19, Seoul, Korea. P. 407.<br /> <br /> Brancalion, P.H., D. Tay, R.R. Rodrigues and A.D. Novembre. 2006. Seed Imbibition of Five Brazilian Native Tree Seeds. 27th International Horticultural Congress, August 13-19, Seoul, Korea. P. 415.<br /> <br /> Castillo, A. 2006. Cyclitol location and movement in planta in soybean (abstract). Cornell University Undergraduate Research Forum (April 19, 2006) 21, 11.<br /> <br /> Chen, F., L. Cseke, H. Lin, A. Kirakosyam, J. Yuan and P. Kaufman. 2006. The study of plant natural product biosynthesis in the pre-genomics and genomics eras. In Natural Products from Plants, Second Edition, CRC Press. pp203-220<br /> <br /> Chen, S.-Y., S.R. Kuo, J.M. Baskin, C.C. Baskin and C.-T. Chien. 2006. Seed dormancy and germination in Neolitsea acuminatissima (Lauraceae). Taiwan J. For. Sci. 21: 125-129.<br /> <br /> Cohn, M.A. 2006. Dormancy: an overview. Black, M.; Bewley, J.D.; Halmer, P. (Eds) Encyclopedia of seeds. Science, technology and uses. Encyclopedia of Seed Biology and Technology. Wallingford, CABI Publishing.<br /> <br /> Contreras, S., M.A. Bennett and D. Tay. 2006. Day-Length During Seed Development Affects Germinability and Storability of Lettuce Seeds. Crop Sci. Soc. Amer. Ann. Meeting, Indianapolis, IN.<br /> <br /> Contreras, S., D. Tay and M.A. Bennett. 2006. Effects of Day-Length during Seed Development in Lettuce (Lactuca sativa L.). Acta Horticulturae, Proceedings of the 27th Int. Hort. Congress. Seoul, Korea. In press.<br /> <br /> Contreras, S., D. Tay and M.A. Bennett. 2006. Effects of temperature during seed development in Lactuca sativa and Helianthus debilis. Amer. Soc. Hort. Sci. New Orleans, LA.<br /> <br /> DeVries, M. and A. S. Goggi. 2006. Determining the extent of frost damage in maize seed using the tetrazolium test. Crop Management doi:10.1094/CM-2006-0414-01-RS.<br /> <br /> Egli, D.B. 2006. The role of seed in the determination of yield of grain crops. Aust. J. Ag. Res. 57: 1237 - 1247.<br /> <br /> Goreta, S. and D.I. Leskovar. 2006. Morphological and physiological modulation of pepper transplants after prolonged exposure to ABA Proceedings 4th Int. Hort. Symposium on Seed, Transplant and Stand Establishment. San Antonio, Texas. p. 28.<br /> <br /> Haagenson, D.M., K.L. Klotz and J.M. McGrath. 2006. Sugarbeet sucrose synthase genes differ in structure and organ-specific and differential expression. J. Plant Physiology 163: 102-106.<br /> <br /> Hall, H. S., M. DeVries and A.S. Goggi. 2006. The effects of moisture content and frost damage on seeds in a maize population. In: 2006 Agronomy Abstracts. The ASA-CSSA-SSSA International Annual Meetings. November 12-16, 2006. Indianapolis, ID.<br /> <br /> He, L., M. B. McDonald and D. Tay. 2006. Dormancy-breaking and germination requirements of evening primrose seeds of Oenothera species. AOSA/SCST meetings, Indianapolis, IN.<br /> <br /> Hewitt JR, P.-P. Liu and H. Nonogaki. 2006. An Arabidopsis mutant exhibiting early arrested embryos with partial desiccation tolerance. The American Society of Plant Biologists Annual Meeting. (Boston, MA)<br /> <br /> Hong, J. and D.J. Cantliffe. 2006. Sensitivity of two lettuce genotypes of abscisic acid during germination. HortScience. Vol. 41. p. 1070. <br /> <br /> Hu, X. 2006. Seed ageing effects on ornamental seed germination and post-germinative growth and comparison of seed vigor tests. M.S. Thesis, Ohio State University.<br /> <br /> Hu, X. and M. McDonald. 2006. A new seed vigor testing system for ornamental species using computerized imaging technology. Amer. Soc. Hort. Sci. New Orleans, LA.<br /> <br /> Hu, X, M. B. McDonald and D. Tay. 2006. A new seed vigor testing system for ornamental species using computerized imaging technology. AOSA/SCST meetings, Indianapolis, IN.<br /> <br /> Hu, X., D. Tay, and M. B. McDonald. 2006. A new seed vigor testing system for ornamental species using computerized imaging technology. 27th Int. Hort. Congress. Seoul, Korea.<br /> <br /> Jifon, J., K. Crosby and D. Leskovar. 2006. Improving stand establishment and disease tolerance of muskmelon by grafting. Proceedings 4th Int. Hort. Symposium on Seed, Transplant and Stand Establishment. San Antonio, Texas. p. 73.<br /> <br /> Jifon, J.L., K.M. Crosby and D.I. Leskovar. 2006. Physiological characteristics of grafted muskmelon grown in Monosporascus cannonballus-infested soil in South Texas. Proceedings of 2006. G.J. Holmes, ed. University Press, North Carolina, p. 23-30.<br /> <br /> Jifon, J., K. Crosby, M. Miller and D. Leskovar. 2006. Establishment and performance of grafted watermelons on Monosporascus cannonballus-infested soil in South Texas. Proceedings 4th Int. Hort. Symposium on Seed, Transplant and Stand Establishment. San Antonio, Texas. p. 32-33.<br /> <br /> Kondo, T., C. Sato, J.M. Baskin and C.C. Baskin. 2006. Post-dispersal; embryo development, germination phenology, and seed dormancy in Cardiocrinum cordatum var. glehnii (Liliaceae s. str.), a perennial herb of the broadleaved deciduous forest in Japan. Amer. J. Bot. 93: 849-859.<br /> <br /> Kosina, S.M. 2006. Enhancing galactosyl cyclitol accumulation in low stachyose, low raffinose soybean lines (abstract). Cornell University Undergraduate Research Forum (April 19, 2006) 21, 45.<br /> <br /> Kozarewa, I., D.J. Cantliffe, R.T. Nagata and P.J. Stoffella. 2006. High maturation temperature of lettuce seeds results in increased ethylene production and germination at elevated temperatures. J. Amer. Soc. Hort. Sci. Vol. 131. pp. 564-570.<br /> <br /> Lawless, P.J., J.M. Baskin and C.C. Baskin. 2006. Scale-dependent classification of xeric limestone prairies: Annual or perennial grasslands? Ann. Missouri Bot. Gard. 93: 455-464.<br /> <br /> Lawless, P.J., J.M. Baskin, and C.C. Baskin. 2006. Xeric Limestone Prairies of Eastern United States: Review and Synthesis. Bot. Rev. 72: 235-272.<br /> <br /> Leskovar, D.I., S. Goreta and J. L. Jifon. 2006. Improving environmental stress tolerance of vegetable transplants. 27th Int. Hort. Congress, Seoul, Korea. p. 403. <br /> <br /> Leskovar, D.I., S. Agehara, T. Shinohara, S. Goreta, and J.L. Jifon. 2006. ABA to enhance stress tolerance of vegetable transplants. Proceedings 4th Int. Hort. Symposium on Seed, Transplant and Stand Establishment. San Antonio, Texas. p.27-28. <br /> <br /> Lin, L., M. Cao, Y. He, J.M. Baskin and C.C. Baskin. 2006. Nonconstituent species in soil seed banks as indicators of anthropogenic disturbance in forest fragments. Can. J. For. Res. 36: 2300-2316.<br /> <br /> Liu P-P and H. Nonogaki. 2006. Functional characterization of the BME3 GATA zinc finger <br /> protein in Arabidopsis seed germination. The American Society of Plant Biologists Annual Meeting. (Boston, MA)<br /> <br /> Liu, Z., Q. Yan, C.C. Baskin and J. Ma. 2006. Burial of canopy-stored seeds in the annual psammophyte Agriophyllum squarrosum Moq. (Chenopodiaceae) and its ecological significance. Plant Soil 288: 71080.<br /> <br /> Martin RC, P.-P. Liu and H. Nonogaki. 2006. MicroRNAs in seeds - Detection techniques and applications. Canadian Journal of Botany 84:189-198.<br /> <br /> McDonald, M. B. 2006. Seed moisture and the equilibrium seed moisture content curve. J. Seed Technol. In press.<br /> <br /> McDonald, M. B. 2006. Physiological causes of seed deterioration in storage. Crop Sci. Soc. Amer. Ann. Meeting, Indianapolis, IN.<br /> <br /> McDonald, M. B. and R. R. Otoni. 2006. Moisture content and temperature effects on three-day-old maize and soybean seedlings using SVIS. Crop Sci. Soc. Amer. Ann. Meeting, Indianapolis, IN.<br /> <br /> McGrath, J.M. 2006. Registration of EL53 sugarbeet germplasm with smooth-root and moderate resistance to Rhizoctonia crown and root rot. Crop Science 46: 2334-2335.<br /> <br /> McGrath, J.M. and D. Trebbi. 2006. Notice of release of TBEL-1 table beet germplasm with high sweetness and cylindrical shape. USDA-ARS Germplasm Release, February, 2006.<br /> <br /> Nagendran, S. 2006. Rhizoctonia disease in sugar beet: Disease screening and cyto- histo-pathology of sugar beet- Rhizoctonia solani interaction. Department of Plant Pathology, Michigan State University. Thesis. 107 pp.<br /> <br /> Nault, B. A., R. W. Straub and A. G. Taylor. 2006. Performance of novel insecticide seed treatments for managing onion maggot in onion fields. Crop Protection 25: 58-65. <br /> <br /> Nonogaki H. 2006. Seed Germination - The biochemical and molecular mechanisms. Breeding Science 56: 93-105.<br /> <br /> Nonogaki, H, P.-P. Liu, J.R. Hewitt, R.C. Martin. 2006. Regulation of seed germination and stand establishment - Importance of repression of developmental programs. 4th ISHS International and 8th National Symposium on Seed, Transplant and Stand Establishment of Horticultural Crops, (San Antonio, TX)<br /> <br /> Otoni, R. R., M. B. McDonald and D. Tay. 2006. The use of x-rays for seed vigor assessment of cotton. AOSA/SCST meetings, Indianapolis, IN.<br /> <br /> Rabara, R. C. 2006. Maturation, drying and storage in lettuce (Lactuca sativa L.) seeds. M. S. Thesis, Ohio State University.<br /> <br /> Rabara, R., S. Contreras, D. Tay, M. A. Bennett and M. B. McDonald. 2006. Development of germinability and desiccation tolerance in lettuce seeds. AOSA/SCST meetings, Indianapolis, IN.<br /> <br /> Rabara, R. C., M. B. McDonald and D. Tay. 2006. Seedling vigor assessment of ultra-dried lettuce (Lactuca sativa L.) seeds. Fourth Int. and 8th National Symp. Seed Transplant and Stand Establ. Of Hort. Crops. San Antonio, TX.<br /> <br /> Rabara, R. C., M. B. McDonald, D. Tay and Y. Vodovotz. 2006. Moisture sorption characteristics of five ornamental species. AOSA/SCST meetings, Indianapolis, IN.<br /> <br /> Rabara, R. C., M. B. McDonald, D. Tay and Y. Vodovotz. 2006. Maturation and desiccation sensitivity in developing seeds of lettuce (Lactuca sativa L.). 27th Int. Hort. Congress. Seoul, Korea.<br /> <br /> Sautu, A., J.M. Baskin, C.C. Baskin and R. Condit. 2006. Studies on the seed biology of 100 native species of trees in a seasonal moist tropical forest, Panama, Central America. For. Ecol. Manage. 234: 245-263.<br /> <br /> Sensenig, E.M. 2006. Cyclitol feeding of immature soybean embryos increases cyclitol accumulation in precociously matured embryos (abstract). Cornell University Undergraduate Research Forum (April 19, 2006) 21, 80.<br /> <br /> Shen, Y., W. Liu, J.M. Baskin, C.C. Baskin and M. Cao. 2006. Persistent soil seed banks of the globally significant invasive species, Eupatorium adenophorum, in Yunnan Province, south-western China. Seed Sci. Res. 16: 157-162.<br /> <br /> Shinohara, T., S. Agehara, S. Goreta and D.I. Leskovar. 2006. Antitranspirant efficacy on stress tolerance of artichoke transplants. Proceedings 4th Int. Hort. Symposium on Seed, Transplant and Stand Establishment. San Antonio, Texas. p. 67-68.<br /> <br /> Stieve, S.M. and D. Tay. 2006. X-ray-assisted flower seed lot improvement. Amer. Soc. Hort. Sci. New Orleans, LA.<br /> <br /> TeKrony, D.M. 2006. Seeds: The delivery system for Crop Science. Crop Sci. 46: 2263-2269.<br /> <br /> Dean Tranel*, Allen Knapp, and Antonio Perdomo. 2006. Tassel development events leading to pollen production: A timeline. In: 2006 Agronomy Abstracts. The ASA-CSSA-SSSA International Annual Meetings. November 12-16. Indianapolis Indiana.<br /> <br /> Turner, S.R., D.J. Merritt, J.M. Baskin, C.C. Baskin, and K. W. Dixon. 2006. Combinational dormancy in seeds of the Western Australian endemic species Diplopeltis heugelii (Sapindaceae). Aust. J. Bot. 54: 565-570.<br /> <br /> Villa, S.T., Q. Xu, A.B. Downie and S.G. Clarke. 2006. Arabidopsis protein repair L-isoaspartyl methyltransferases: Predominant activities at lethal temperatures. Physiol. Plant. 128: 581-592.<br /> <br /> Watkinson, J.O. and G.E. Welbaum. 2006. Seeds of Orchidaceae In: M. Black, D. Bewley, P. Halmer, ed. Encyclopedia of Seeds. CABI, Cambridge, UK.<br /> <br /> Welbaum, G.E. 2006. Seeds of the Family Cucurbitaceae In: D. Bewley, M. Black, P Halmer ed. The Encyclopedia of Seeds. CABI International Wallingford UK. <br /> <br /> Welbaum, G.E. 2006. Natural defense mechanisms in seeds In: A.S Basra, ed. Handbook of Seed Science and Technology. Food Products Press, Binghampton, NY. <br /> <br /> Woltz, J.M., D.B. Egli and D.M. TeKrony. 2006. Corn seed germination and vigor following freezing during seed development. Crop Sci. 46: 1526-1535.<br /> <br /> Wu, Q-J., J. Z. Zhao, A. G. Taylor and A. M. Shelton. 2006. Evaluation of insecticides and application methods against swede midge, a new invasive pest in the US. J. Econ. Entomol., 99: 117-122.<br /> <br /> Xiang, C. 2006. Biodegradable non-woven fabrics electrospun from renewable polymers for controlled release delivery of chemicals. MS thesis. Cornell University<br /> <br /> Xu, L., K. Fujimura and M. B. McDonald. 2006. Automatic separation of overlapping seedlings by network optimization. Seed Sci. & Technol. In press.<br /> <br /> Yang, Y. J.S. Yuan, J. Ross, J.P. Noel, E. Pichersky and F. Chen. 2006. An Arabidopsis thaliana methyltransferase capable of methylating farnesoic acid. Arch. Biochem. Biophy. 448: 123-132 <br /> <br /> Yildirim, E., A. G. Taylor and T. D. Spittler. 2006. Ameliorative effects of biological treatments on growth of squash under salt stress. Scientia Horticulturae 111: 1-6<br /> <br /> Yuan, J.S., J. Adamczyk, K.D. Gwinn and F. Chen. 2006. Identifying and characterizing rice terpene synthase genes involved in insect defense using an integrated functional genomics approach. Presented at the American Society of Plant Biologists annual meeting held at Boston, MA <br /> <br /> Yuan, J.S., J. Adamczyk, D. Trently, K.D. Gwinn and F. Chen. 2006. Characterizing chemical defenses of rice against insects using integrated functional genomics. Presented at the Arthur M. Sackler Colloquia of the National Academy of Sciences-From Functional Genomics of Model Organisms to Crop Plants for Global Health-held at Washington D.C.<br /> <br /> Yuan, J.S., A. Reed, F. Chen and C.N. Stewart. 2006. Statistical analysis of real-time PCR data. BMC Bioinformatics 7:85 <br /> <br /> Yuan, J.S., F. Chen, N. Stewart. 2006. Statistical methods for efficiency adjusted real-time PCR quantification. Presented at UT-ORNL-KBRIN Bioinformatics Summit-held at Cadiz, KY <br /> <br /> Yuan JS, X. Yang, J. Lai, H. Lin, Z.M. Cheng, H. Nonogaki and F. Chen. 2006. The endo-²-mannanase gene families in Arabidopsis, rice and poplar. Functional and Integrative Genomics, in press.<br /> <br /> Zhang, Q. 2006. Accumulation of soluble carbohydrates during soybean seed growth and maturation (abstract). Cornell University Undergraduate Research Forum (April 19, 2006) 21, 103.<br /> <br /> Zhao, T-Y, J.W. Corum III, R.B. Meeley, J.T. Mullen, T. Helentjaris, D. Martin and B. Downie. 2006. ALKALINE a-GALACTOSIDASE is present in maize seeds and cultured embryo cells, and accumulates during stress. Seed Sci. Res. 16: 107-121.<br /> <br /> Zhao, N., J. Guan, X. Yang, Z.-M. Cheng and F. Chen. 2006. Functional genomic characterization of the SABATH family of methyl transferases in poplar (Populus trichocarpa). Presented at the Arthur M. Sackler Colloquia of the National Academy of Sciences-From Functional Genomics of Model Organisms to Crop Plants for Global Health-held at Washington D.C.<br /> <br /> <br /> <br />

Impact Statements

1. Identification of QTL for high temperature germination in lettuce and associated molecular markers will facilitate the introgression of this trait into cultivars adapted for desert production. Two distinct QTL from different sources may allow pyramiding of these loci to provide broad high temperature tolerance, reducing the risk of stand failures during warm weather plantings.
2. Studies on the mechanisms of seed deterioration must employ appropriate conditions to obtain results that will be valid under commercial storage conditions, as the mechanisms of seed aging and deterioration may differ under different conditions of temperature and moisture content. New methods to model the effects of oxygen on germination and to measure seed respiration rates during germination can be applied to assess and study vigor and dormancy.
3. By defining optimal hydrothermal priming through the EBM assay, the lettuce protocol may be useful for other endospermic species including tomato, pepper, carrot, and celery. By using this model developed for lettuce, the seed industry can improve the efficiency and consistency of results of the priming process for different vegetable seed species, cultivars, and seed lots.
4. The U.S. annually exports more than $750 million in seed. Most of the hybrid maize seed is produced in the Midwestern states, where early-Fall killing frosts are not uncommon. Immature maize seed can suffer severe mechanical and biochemical damage due to freezing, and understanding the physiological and molecular changes associated with freezing injury will allow early prediction of damage and possible remediation.
5. Discovery of molecular markers on a tomato chromosome tightly linked to brownseed1 will bring us one important step closer to identification of the gene responsible for this intriguing lesion and underlying mechanism of communication between the endosperm/embryo and the overlying testa. Use of this genetic tool will facilitate functional genetics of tomato seed development.
6. Wild rye (Elymus) species are ecologically important shade tolerant grasses native to North America. Dormancy release treatments developed for these species will improve stand establishment for native plant restoration projects in ecologically sensitive areas.
7. Salinity affects an increasing number of soils worldwide each year, and sugar beets have an ability to grow in and perhaps help reclaim saline soils. However, sugar beet is most sensitive to salt during germination, and the current work indicates this salt sensitivity during germination can be reduced.
8. A minor chemical component in many seeds was conclusively identified and purified from buckwheat seed extracts. This knowledge can now be used to assess its importance in seed quality.
9. Laboratory scale seed coating equipment was refined for seed treatment application using rotary pan technology, one of the W-1168 milestones. Seed treatment projects were designed and implemented for eleven projects covering nine states.
10. Drying lettuce seeds to moisture contents less than 1% had little or no effect on seed germination and vigor. Desiccation tolerance is acquired early during lettuce seed development and drying seeds to very low moisture contents can be used to enhance seed storage ability.
11. Image processing can be used to both identify seeds and determine seedling growth. When this system is applied, it has been shown that substratum moisture content and germination temperature must be precisely controlled to ensure standardization of seedling growth.
12. Characterization of enhancer-trap and knockout lines led to the identification of a component potentially involved in ABA signal transduction and ABA-auxin crosstalk. This research has identified a novel hormonal regulatory mechanism in seed germination.
13. Discovery of miRNA involved in gene regulatory networks suggest that seed responses to hormones, which are of agricultural importance, can be modified by altering miRNA or their target gene expression. miRNA approaches will allow new methods to improve seed and seedling performance through novel methods.
14. Mannanase genes are expressed in seeds of crop species such as pepper and lettuce. This gene can be used as a germination marker for seed research and seed enhancement treatments such as priming.
15. A number of genes potentially involved in controlling red rice seed dormancy and the genes critical for dormancy breaking have been identified. Further functional characterization of these genes will provide insight into the molecular mechanisms of seed dormancy and dormancy breaking.
16. The identification of all endo-beta-mannanase genes expressed in germinating seeds of Arabidopsis and rice provides a roadmap into the further investigation of the functions of individual endo-beta-mannanase gene in seed germination.
17. Orchid seed are notoriously difficult to store for long perioids of time while maintaining viability. Research indicated cryopreservation of Brassia and Phalaenopsis seeds is a viable technique for long-term orchid germplasm conservation.
18. Controlled osmotic stress after germination may be a viable alternative to synthetic chemical plant growth regulators to control plant height of bedding plants. Research showed promising results in using alternatives to current chemicals, but suggested they require more precise management for effective height control.
19. Mutations in the GA signaling gene SLEEPY1 (SLY1) are associated with increased seed dormancy and increased protein levels of the negative regulator of seed germination RGL2. RGL2 protein levels do not decrease after sly1 afterripening, suggesting that an RGL2-independent mechanism is involved.
20. ABA treatment applications prior to field transplanting is effective to modulate shoot growth, enhance stress tolerance and ultimately improve field establishment of pepper and artichoke transplants.

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Report Information

Participants

Allen, Phil () - Brigham Young University;
Asahina, Masa ()- Oregon State University;
Bennett, Mark (bennett.18@osu.edu) - The Ohio State University;
Bradford, Kent (kjbradford@ucdavis.edu) - University of California, Davis;
Cantliffe, Daniel (djc@mail.ifas.ufl.edu) - University of Florida;
Cohn, Marc (mcohn@lsu.edu) - Louisiana State University;
Dirk, Lynnette (ldirk@uky.edu) - University of Kentucky;
Downie, Bruce (adownie@uky.edu) - University of Kentucky;
Duggan, Brian (brian.duggan@oregonstate.edu) - Oregon State University;
Geneve, Robert (rgeneve@uky.edu) - University of Kentucky;
Knapp, Allen (adknapp@iastate.edu) - Iowa State University;
Lemaux, Peggy (lemauxpg@nature.berkeley.edu) - University of California, Berkeley;
Leskovar, Daniel (d-leskovar@tamu.edu) - Texas A&M University;
McDonald, Miller (mcdonald.2@osu.edu) - The Ohio State University;
McGrath, Mitch (mitchmcg@msu.edu) - Michigan State University;
Misra, Manjit (mkmisra@iastate.edu) - Iowa State University;
Nonogaki, Hiro (hiro.nonogaki@oregonstate.edu) - Oregon State University;
Norcini, Jeff (wldflowr@ufl.edu) - University of Florida;
Perry, Sharyn (sperr2@uky.edu) - University of Kentucky;
Steber, Camille (csteber@wsu.edu) - Washington State University;
Still, David (dwstill@csupomona.edu) - Cal Poly;
Taylor, Alan (agt1@cornell.edu) - Cornell University;
Welbaum, Greg (welbaum@vt.edu) - Virgina Polytechnic Institute and State University

Brief Summary of Minutes

The annual meeting of the W-1168 meeting was convened in Davis, CA on September 15 and 16, 2007. The goals of the meeting were two-fold, and as such, did not conform to the traditional presentations of state reports, but rather was geared to 1) participating in the success of the penultimate W-1168 goal of organizing an integrative seed science symposium, and 2) formally initiating the process that will lead to submission of a new project outline to over the period from October 2008 through 2013. Both goals were met.

Over the past three years, W-1168 members substantially contributed to the organization and presentation of the four-day symposium (September 17-20, 2007) "Translational Seed Biology: From Model Systems to Crop Improvement", hosted by the UC Davis Plant Sciences Department (see website for details: www.plantsciences.ucdavis.edu/ seedsymposium2007/).

The balance of the W-1168 meeting was devoted to discussion of future activities, including developing a revised project outline.

In summary, this meeting was very productive in terms of information gathered and disseminated. Scientifically, the symposium was second to none in providing current, detailed perspectives across the whole range of seed biology topics. Administratively, the meeting set the stage for the next five years by highlighting current broad research activities of the W-1168 membership and solidifying research linkages between many members.

Accomplishments

We are using the latest technologies, and improving existing as well as developing new techniques to investigate the central questions of seed biology and seed delivery systems. To ensure that end users have an abundant supply of high quality seeds, this proposal has established three objectives:<br /> <br /> 1. Identify and characterize biophysical, biochemical, genetic and environmental factors regulating or influencing seed development, germination, vigor and dormancy.<br /> <br /> 2. Determine and model the biotic and abiotic factors affecting seed germination, seedling emergence and establishment of sustainable populations in natural and agro-ecological systems.<br /> <br /> 3. Develop, evaluate and transfer technologies to assess and improve seed and seedling quality, health, performance, utilization, and preservation.<br /> <br /> These objectives are necessarily broad and reflect the diversity of stakeholder needs, the gaps in current knowledge that can be addressed by new technologies such as genomics, and the promise that proven and new technologies can yield practical solutions to complex seed biology issues relating to seed dormancy and germination, seedling vigor, and establishing or re-establishing high plant stands for all species in their respective applications. In most cases, the technical feasibility of the research procedures is proven as standard practice in the case of field-oriented research, or as an extension of established genetic, biochemical, and physiological principles. Results from genomic and proteomic approaches will likely yield new insights for practical application; however, there will likely be a time lag between discovery and adoption beyond the scope of this proposal.<br /> <br /> Members from 11 states are working on projects that relate to Objective 1, five states activities address issues relating to Objective 2, and nine states have technology transfer projects with major focus on Objective 3 goals, with primary attention to more than 25 distinct species as their model systems. These objectives are not mutually exclusive, but represent the continuum between basic and applied research in meeting seed user needs for the future. We are one of the longest running multistate working groups in the USDA, with origins in the late 1970s. Our members are internationally recognized authorities on seed science, with many demonstrated accomplishments including two major seed-oriented symposia in the last five years, dozens of books and book chapters, hundreds of peer reviewed journal articles, and deployment of a series of on-line educational courses. Within the present group, at least 30 collaborations have yielded demonstrated results, and many additional projects are ongoing and planned. It is highly likely that the future feasibility of achieving successful results through multistate collaboration is assured, given the prominence and productivity of the members of W-1168 in the recent past, as well as over the history of this multistate activity.

Publications

Impact Statements

1. 1. Biological sciences are rapidly generating data and information about biochemical processes and mechanisms that control growth and development and the response to an organisms environment. Assessing and applying this knowledge for the benefit of seed science and technology was the purpose of a W-1168 co-sponsored symposium. The symposium highlighted numerous opportunities and challenges for seed biology, and scientists can now better evaluate strategies for meeting seed technology needs with state of the art approaches.
2. 2. Seed science is faced with an exceptionally diverse array of topics, methods, and species for which specific information is needed to improve their overall performance in a particular application. The W-1168 membership is active in all phases of seed biology. Reducing this diversity to general principles is a promising outcome that can be achieved through continued close associations of seed scientists such as those in this group.

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