2006 Annual Report 1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? Faced with a challenging environment for growing wildrice, producers need improved varieties to meet those challenges. Breeding objectives for new varieties must include resistance to shattering, disease, and lodging, as well as higher yield. First, growers continue to express the need for varieties that are more shattering-resistant and that are genetically fixed for nonshattering. A two-pronged approach is being taken to shattering resistance: conventional plant breeding to increase quantitative shattering resistance and development of marker-assisted selection to fix major genes for nonshattering and eliminate reversion to the shattering wild-type in new varieties. Second, disease resistance continues to be a major need in Minnesota. Fungal Brown Spot (FBS) caused by Bipolaris oryzae is the primary foliar disease. Also, Spot Blotch (SB) caused by B. sorokiniana is becoming more important, especially as resistance to FBS has increased. Disease resistance improvements will focus on: inoculation and field selection of individual plants and families, and inbred lines for resistance to Bipolaris and other diseases; further refinement of inoculum production and selection methodologies; and use of mapping populations in order to map and develop markers for resistance to wildrice diseases. Third, lodging has been a factor in yield losses as well. Efforts to breed for lodging resistance should involve both selection for lodging resistance and development of semidwarf lines as parents for potential semidwarf varieties. Fourth, higher yield potential is needed for Minnesota wildrice farms to remain profitable in the face of declining prices. A very early maturing variety is needed to enable growers to harvest before the older shattering plants drop a large amount of seeds and perpetuate the treadmill of shattering. An added benefit to an early variety will be to extend the harvest season, relieving both the producer and the processor of some time pressures. Finally, some agronomic research is needed in order to determine the optimum fertilization requirements and harvest date for growers to achieve the increased yield potential for improved varieties. Continued progress in breeding depends on improved understanding of the genetics of key traits and the discovery of new traits and alleles. This research project will focus on adding SSR (simple sequence repeat) markers to the molecular map of wildrice and developing "breeder-friendly" markers--SSRs and ESTs (expressed sequence tagged sites). Because shattering genes have been difficult to eliminate by simple selection, such markers can be used to identify and eliminate plants within breeding populations and varieties that harbor unexpressed shattering alleles. The markers that are on the wildrice map will also be used as a fingerprinting tool. Marker sets will be identified and tested for efficacy in distinguishing varieties, breeding populations, and wild populations. Populations with unique profiles may be further characterized for traits useful in breeding. As new traits are discovered, lines will be developed with these traits for future genetic characterization. In addition, markers may also be used to detect outside pollination from other populations and to better understand the isolation distances needed to keep varieties and natural stands from affecting each other. Marker profiles may also be used to identify potential heterotic combinations of breeding populations to maximize hybrid vigor. Breeding programs require genetic variability as "raw material" to make progress in selection for known traits and as sources of new traits. Wildrice varieties and breeding populations already contain significant genetic variability. However, wild populations might still yield new traits or new alleles for traits not apparent in breeding populations. The genetic resources of wildrice will be collected and evaluated in order to preserve germplasm and discover traits and new sources of traits. Newly discovered traits (seed length, seed nondormancy, dwarfing genes) will be studied for inheritance and associated markers in order to more effectively cross them into adapted varieties. This research contributes to National Program 301, Plant Genetic Resources, Genomics and Genetic Improvement. 2.List by year the currently approved milestones (indicators of research progress) 2004 - Develop methods for the production of consistently high numbers of viable spores of Bipolaris oryzae and B. sorokiniana. - Develop an experimental line uniform enough for physiological and fertilization studies. - Add at least 100 SSR markers to the wildrice RFLP molecular genetic map. - Identify SSR or EST markers that are more tightly linked to shattering genes. 2005 - Release an early-maturing variety fixed for at least one major nonshattering gene using molecular markers to screen out shattering. - Develop an experimental line fixed for white flower color that can be used to detect pollination from foreign sources. - Develop protocols for production and delivery of inoculum of stem rot organisms and/or Fusarium spp. as the causal agent of head blight. 2006 - Create at least five new elite breeding populations for testing by crossing two or more inbred lines for each population. - Identify a fungicide to more effectively (than the currently labeled product, propiconazole) control the Bipolaris diseases and stem rot caused by Nakataea sigmoidea. 2007 - Locally store 20 or more cultivars, breeding populations, and wild populations at -5C or on liquid nitrogen. - Collect and deposit (with passport data) at least 10 cultivars, breeding populations, and wild populations in the National Center for Genetic Resources Preservation. - Develop molecular marker sets that can effectively distinguish different varieties, breeding populations, and wild populations. - Develop from a breeding population at least 200 first or second generation inbred lines with enough seeds to test in replicated rows. - Breed improved populations and lines for resistance to stem rots through selecting among inoculated plants and lines. 2008 - Release a high-yielding variety with superior resistance to both fungal brown spot disease and spot blotch, and fixed for nonshattering. - Estimate the distance pollen can travel to effectively pollinate a distant stand, quantifying the level of contribution of such pollen compared to native pollen. - Release a short-statured, high-yielding variety fixed for nonshattering. - Carry out combined half-sib and S1 family selection for at least two cycles to improve a breeding population for yield and other traits. - Develop experimental lines that are fixed for one, two, or all three shattering genes, for comparison of the effects of each gene. - Test susceptibility of current varieties, populations, and/or inbred lines to stem rots and Fusarium head blight. 4a.List the single most significant research accomplishment during FY 2006. None. 4b.List other significant research accomplishment(s), if any. None. 4c.List significant activities that support special target populations. None. 5.Describe the major accomplishments to date and their predicted or actual impact. Approximately 29 SSR markers have been added to the current RFLP map. This provides a more useful map, linking traits of interest to PCR-based markers that can be used more easily for marker-assisted selection. The markers will eventually result in varieties with desired genotypes with respect to nonshattering and other traits, which should improve productivity and longevity of new varieties. As the molecular genetic map of wildrice is refined, benefits to rice researchers working on traits common to both species should accrue. The methodology for growing Bipolaris sorokiniana spores has also been greatly improved. Spores can now be produced in large quantities and with high viability. This enables reliable inoculation of breeding lines to select for resistance to this disease. This method has already been used to produce inoculum that was spread on this year's breeding nursery to test for susceptibility to spot blotch, increasing the likelihood of finding cultivars resistant to this disease. Half-sib families from an elite breeding population were tested in replicated rows for resistance to Bipolaris oryzae, B. sorokiniana, and Nakataea sigmoidea. Heritability for resistance to these diseases were estimated. This will help determine the most effective method of selecting for resistance to these diseases, whether by progeny (family) selection or individual plant selection. Ten populations were inoculated with sclerotia of Nakataea sigmoidea grown using methods developed in this project. These were phenotypically selected for resistance to stem rot and other traits, marking the first attempt to select for resistance to this disease. If sufficient progress is made, resistance to this disease could reduce the need for fungicides to control the disease. The research conducted in this project addresses objectives in NP 301, Plant Genetic Resources, Genomics and Genetic Improvement. 6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Knowledge has been communicated to Minnesota wildrice producers at the annual wildrice field day held at the North Central Research and Outreach Center (NCROC), and at the wildrice winter meetings sponsored by the Minnesota industry. Current experiments and research progress are discussed with growers. Knowledge is also shared with a wildrice extension advisor/researcher in California involved with collaborative experiments, who was also invited to the NCROC wildrice field day to give a presentation and interact with growers and scientists. Personnel on this project also attend meetings and interact with scientists at the national and international level, some of whom are involved with related research on rice. There is some constraint to the speed of adoption of new varieties related to the difficulty of eliminating significant amounts of carry-over seeds of older varieties. Seed dormancy limits variety increases to one generation per year. Also, once released, the limitations on seed storage preclude maintaining the availability of seed of that variety after the first few years following release, because it has to be grown out every year in order for seed to be available. Once in growers' paddies, the variety can cross-pollinate with volunteer plants in the paddy and with adjacent paddies of other varieties, degenerating the variety's genetic integrity. 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Technical, non-peer-reviewed: Porter, R.A., Braaten, D.M., Carey, L.L., Schumer, H.J. 2006. Wildrice breeding: variety testing. In: Minnesota Wildrice Research—2005, Minnesota Agricultural Experiment Station. p. 35-39. Porter, R.A., Marcum, D.B., Braaten, D.M. 2006. Effect of water depth on seed length and productivity parameters. In: Minnesota Wildrice Research—2005, Minnesota Agricultural Experiment Station. p. 40-44. Kahler, A.L., Porter, R.A., Phillips, R.L. 2006. Marker-assisted selection for non-shattering wildrice. In: Minnesota Wildrice Research—2005, Minnesota Agricultural Experiment Station. p. 12-16. Kosbau, N., Porter, R.A. 2006. GIS Integration: interpretation of aerial photos in wildrice. In: Minnesota Wildrice Research—2005, Minnesota Agricultural Experiment Station. p. 5-11. Nyvall, R.F., Porter, R.A., Carey, L., Braaten, D.M., Schumer, H.J. 2006. Control of foliar and stem diseases. In: Minnesota Wildrice Research—2005, Minnesota Agricultural Experiment Station. p. 26-34. Porter, R.A., Nyvall, R.F., Carey, L.L. 2005. Assessing the reaction of American wildrice cultivars to inoculated stem rot pathogens [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Abstract No. 607b. Kahler, A.L., Porter, R.A., Phillips, R.L. 2005. Marker-assisted selection for non-shattering wildrice (Zizania palustris) [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Abstract No. 846a. Marcum, D.B., Porter, R.A. 2005. Influence of water depth upon plant development, yield and seed size of modern wildrice cultivars [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Abstract No. 622b.