2004 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? What does it matter?
Improvement of rice for yield, grain quality, and pest resistance is required to keep the US rice industry competitive in the global marketplace. Stepwise approaches are undertaken in this project to: .
1)Base broaden US rice germplasm through development of adapted indicas, which are grown in three-fourths of the world but not in this country. Indicas come from the tropics and originally were not adapted to high-latitude areas such as the US, so the US has relied on japonica rice. In recent decades high-yielding, pest-resistant indicas that will grow in the US have become available, but most do not have satisfactory grain quality for our markets. Therefore research is underway to create indicas possessing not only high yield but also satisfactory quality. .
2)Develop germplasm with improved and novel grain qualities, including giant embryo, altered fatty acid patterns, increased grain length in aromatic germplasm, and amylopectin starch chain lengths. .
3)Find and incorporate new genes for pest resistance into cultivated rice from crosses with related wild species of rice. Typically, wild relatives of any crop are reservoirs of pest resistance genes, and such opportunities also exist for rice. .
4) Continue to evaluate the US rice collection of 17,000+ entries by forming a core subset of about 10%, or 1700 entries. Develop a Genetic Stocks--Oryza (GSOR) collection to collect and preserve mutant stocks, mapping populations, and trisomics.
All of this work is relevant to US rice breeders, who look to these basic programs for accessing germplasm that is useful in development of improved varieties. The potential impact is large inasmuch as this work lays the long-term foundation for US rice improvement.
2.List the milestones (indicators of progress) from your Project Plan.
Objective 1. Develop early maturing, production-efficient, indica rice germplasm.
Milestone 1 (12 months) - Release Zhe 733/IRRI indica lines as germplasm to rice breeders. Evaluate M5 of early indica mutants. Produce M1 of newer indicas. Publish release papers on 11 semidwarf mutants.
Milestone 2 (24 months) - Evaluate early mutants. Hybridize selected germplasm lines with additional indicas. Search for dominant genetic sterility in indicas.
Milestone 3 (30 months) - Release early mutants. Integrate more indicas (from Objective.
4)into crossing program.
Milestone 4 (48-60 months) - Evaluate new crosses in F2, F3, and F4. Publish multi-year summary of indica base-broadening.
Objective 2. Develop rice germplasm with improved and novel grain qualities...
Milestone 1 (12 months) - Acquire giant embryo mutants. Survey 20 cultivars for fatty acid patterns. Evaluate grain length in aromatic se germplasm composite components. Evaluate ApCLP of cultivars with similar amylose. Publish papers on KBNT lpa1-1 and aromatic se.
Milestone 2 (24 months) - Search for new lpa mutants. Assay oil content of giant embryo mutants. Publish survey on fatty acid patterns in rice. Initiate screening for fatty acid mutants.
Milestone 3 (30 months) - Study inheritance of giant embryo mutants. Initiate inheritance studies on altered fatty acid mutants. Grow F1 and F2 generations of aromatic se/new basmati cultivars. Grow additional cultivars for ApCLP comparisons.
Milestone 4 (48-60 months) - Determine whether further searches for fatty acid variants are needed. Evaluate F3 and F4 of aromatic se/new basmatis. Examine cultivars grown in growth chamber for physical and thermal characteristics and ApCLP. Publish results on oil and fatty acid studies.
Objective 3 - Introgress new genes for pest resistance into cultivated rice from wide crosses.
Milestone 1 (12 months) - Complete screening of available Oryza spp. for resistance to blast and sheath blight. Confirm IR36 trisomics brought through quarantine. Obtain additional Oryza spp. from cooperating institutions.
Milestone 2 (24 months) - Begin screening the additional Oryza spp. for sheath blight and blast resistance. Publish data describing the Oryza spp. blast and sheath blight resistance. Begin field evaluation of introgressed Oryza spp. germplasm for disease resistance.
Milestone 3 (30 months) - Develop procedures to screen the Oryza spp. for resistance to rice water weevil.
Milestone 4 (48-60 months) - Release blast resistant germplasm from introgression of Oryza spp. Release genetic stock of tetraploid sterile. Publish data on rice water weevil resistance in Oryza spp.
Objective 4 - Evaluate germplasm and establish a Rice Genetic Stocks Collection.
Milestone 1 (12 months) - Form core subset and evaluate for agronomic characters. Rejuvenate low inventory materials. Inaugurate Rice Genetic Stocks Collection.
Milestone 2 (24 months) - Make seed available and evaluate half of the core. Collect data on molecular marker analysis. Keep collecting rice genetic stocks.
Milestone 3 (30 months) - Complete evaluation of the core. Keep up with rejuvenation and new germplasm seed increase. Keep collecting genetic stocks.
Milestone 4 (48-60 months) - Continue evaluation and documentation of Rice Genetic Stocks Collection. Publish paper on the status and availability of the Rice Genetic Stocks Collection.
A. List the milestones that were scheduled to be addressed in FY 2004. How many milestones did you fully or substantially meet in FY 2004, and indicate which ones were not fully or substantially met, briefly explain why not, and your plans to do so.
FY2004 milestones are those indicated for 12 months.
Objective 1. All of the objectives are on schedule to be completed during this growing season. Nine Zhe 733/IRRI indica germplasm lines are being released as indica-1 to indica-9. Eighteen early maturing M5 mutants of indica lines are in a preliminary yield test. These have grain quality approaching US standards, but the original parents were too late for the US. The mutants are 10 to 15 days earlier than the parents, and thus are comparable in maturity to US cultivars. The M1 generation of four newer indica germplasms were grown in the Puerto Rico winter nursery, and the M2 generation is in the field this season, with selection being practiced for double dwarfs, as the original single dwarf material was about 120 cm tall, which is 20 to 30 cm taller than desired. The release papers on 11 semidwarf mutants were published in Crop Science in 2004.
Objective 2. Portions were met, others are in progress. Seven rice lines were grown in Arkansas yield tests in four different locations. The starch of each was evaluated for their physical and thermal characteristics using HPLC, DSC, RVA. DNA analyses were added to determine genetic variation in the enzymes that are responsible for starch structure. This data will add to the information of how temperature affects starch structure. A giant embryo mutant was induced and seeds are being increased so that it can be analyzed for its fatty acid profile. Grain length was measured in aromatic rices, and papers were publish on KBNT lpa1-1 and aromatic se germplasm.
Objective 3. Complete screening of available Oryza spp. for resistance to blast and sheath blight. - The additional Oryza spp. accessions with adequate seed available have been screened for resistance to all races of blast found in the US. Seed of missing accessions is being collected for screening. In view of changing to a more efficient inoculation method for sheath blight, studies comparing a single leaf inoculation technique to the previously used whole-plant method were conducted. For this reason, additional inoculations of additional Oryza spp. accessions are still in progress.
Confirm IR36 trisomics brought through quarantine. - 27 of the available IR36 rice trisomic lines have been identified. In some cases additional panicles are being collected for meiotic analysis.
Obtain additional Oryza spp. from cooperating institutions. - Seed of the progeny from three different Oryza sp./cultivated rice populations was obtained, and these are being grown. Plans for obtaining additional Oryza spp. accessions that have been through the quarantine process are in progress.
Objective 4. The USDA rice core collection was formed with 1801 accessions, including 11 Oryza species, originating from 115 countries. Seed stocks of the core are maintaned in the DB NRRC for comprehensive evaluations. Evaluations of agronomic and grain morphology descriptors were completed, and disease and insect evaluations are underway. Samples of brown and milled rice of 1614 accessions were prepared for evaluating grain quality descriptors and for molecular marker analyses for quality. DNA fingerprinting analyses are underway. Two indica germplasm introductions, 4484 and 4582, were included in the Uniform Rice Nursery grown in five state in the South for two years. Compared with two widely grown US cultivars, Francis and Wells, the indicas were similar in yield for both rough and milled rice, and for grain quality, as indicated by grain shape and amylose content, but had superior resistance to blast and sheath blight diseases. The Genetic Stocks--Oryza (GSOR) collection was inaugurated in August 2003, with 19 entries to date.
B. List the milestones that you expect to address over the next 3 years. What do you expect to accomplish, year by year, over the next 3 years under each milestone?
Milestone 2 (FY05). Publish Crop Science paper on germplasm release of nine Zhe 733/IRRI indica lines. Further evaluate 18 early maturing indica mutants of IRRI germplasm, for yield and grain quality characters, in order to reduce number to best five or six selections. Also evaluate 21 early maturing indica mutants of Oryzica llanos 5 (OL5), a very late but extremely blast-resistant cultivar from South America. Such early maturing mutants of OL5 have potential for further breeding uses in the U.S. Hybridize selected indica germplasm lines with newer indicas from Asia. As the search for dominant genetic sterility in indicas was not successful in FY04, probably bring this aspect to a close in FY05.
Milestone 3 (FY06). Release selected early maturing indica mutants of IRRI germplasm and of OL5. Integrate more indicas (from Objective.
4)into indica x indica crossing program, and grow F1s of previous crosses.
Milestone 4 (FY07). Evaluate new indica x indica crosses in F2, F3, and F4. Publish papers on indica x indica base-broadening efforts involving the two major early maturity mutant groups, from IRRI germplasm and from OL5.
Milestone 2 (FY05). Search for new grain quality mutants, with special reference to amylose content mutants. Assay embryo size and oil content of a giant embryo mutant of Drew. Conduct survey on fatty acid patterns in approximately 20 U.S. rice cultivars. Initiate screening for fatty acid mutants in previously mutagenized populations.
Milestone 3 (FY06). Study inheritance of giant embryo mutant. Assuming that fatty acid mutants are found, initiate inheritance studies on these mutants. Grow F1 and F2 generations of aromatic se/new basmati cultivars. Evaluate early maturing and semidwarf mutants of jasmine rice. Grow additional cultivars for amylopectin starch comparisons. Rice starch is composed of amylose, ca. 20%, and amylopectin, ca. 80%. While much is known about the amylose fraction, relatively little is known about the amylopectin fraction, which may be responsible for taste variations in rice cultivars.
Milestone 4 (FY07). Determine whether further searches for fatty acid variants are needed. Evaluate F3 and F4 of aromatic se/new basmatis. Examine cultivars grown in growth chamber for physical and thermal characteristics and amylopectin starch comparisons. Publish results on oil and fatty acid studies, and on amylopectin starch variations.
Milestone 2 (FY05). Begin screening the additional Oryza spp. for sheath blight and blast resistance. Publish data describing the Oryza spp. blast and sheath blight resistance. Begin field evaluation of introgressed Oryza spp. germplasm for disease resistance, especially for blast disease.
Milestone 3 (FY06). Continue field evaluation of introgressed Oryza spp. germplasm, for blast and sheath blight resistance. Develop procedures to screen the Oryza spp. for resistance to rice water weevil.
Milestone 4 (FY07). Release blast-resistant germplasm from introgression of Oryza spp. Consider release of genetic stock of tetraploid sterile, as a breeding tool for making wide crosses with other grass genera. Publish data on rice water weevil resistance in Oryza spp.
Milestone 2 (FY05). Make seed available and aggressively evaluate half of the core collection of 1801 accessions. Collect data on molecular marker analysis for grain quality factors of the collection. Add the 353-line KBNT lpa 1 x ZHE 733 mapping population to the rice genetic stocks collection. Prepare cooperative research project proposals with rice scientists in China. Our objective is to secure additional indicas; the payoff for Chinese scientists is to obtain training in U.S. labs.
Milestone 3 (FY06). Complete evaluation of the core collection of 1801 accessions. Keep up with rejuvenation and new germplasm seed increase. Expand the genetic stocks collection to include potentially thousands of molecular mutant stocks from cooperating NSF projects around the nation. Introduce through quarantine the newer indica stocks expected from the cooperative projects with China.
Milestone 4 (FY07). Continue evaluation and documentation of Rice Genetic Stocks Collection. Publish paper on the status and availability of the Rice Genetic Stocks Collection. Begin evaluation of new indica germplasm obtained from cooperative research projects in China.
4.What were the most significant accomplishments this past year?
A. Single most significant accomplishment during FY 04:
Release of nine improved indica germplasms -
Nine germplasms from indica x indica crossing were released to interested breeders. This is important because this is the first example of high-yielding indica rice germplasm possessing both adaptation to this country and intermediate amylose similar to US long grains, in a nation that to date grows only japonica rice. This was done by crossing a very early maturing, high-amylose indica variety from China with later maturing indicas from IRRI that had the desired intermediate amylose level, then selecting recombinants that have both early maturity and intermediate amylose. The impact is that this enables breeders to better access improved indica germplasm, which has the potential for increasing productivity of rice in the US.
B. Other significant accomplishments:
Publication of germplasm registrations -
In 2004 a paper was published on six induced semidwarf mutants, followed closely by a second paper on five more semidwarf mutants. This is important because these papers document the availability of additional semidwarfing sources, each possessing a semidwarfing gene nonallelic (different from) the sd1 gene in worldwide use. Mutants that were 10 to 25% shorter than the parents were induced in five tall Arkansas varieties, LaGrue, Kaybonnet, Adair, Katy, and Orion, with selection for productivity at least equal to the parent. The impact is that this provides additional semidwarfing genes, should alternatives be needed to the worldwide sd1 source.
Evaluation of core collection -
The USDA core collection of 1801 entries from 115 countries was evaluated for straighthead reaction at the straighthead evaluation site at Stuttgart. This is important because in the absence of straighthead-resistant commercial cultivars, about 35% of rice fields in Arkansas are drained and dried for straighthead prevention, a practice that stresses plants and increases costs for labor, power, and water usage. On a 1-to-9 scale, 26 entries were found to have straighthead resistance ratings from 1.3 to 3.0, compared with a susceptible rating of 8.0 for Cocodrie, a widely grown US cultivar. The impact of this research is that resistant germplasm has been identified that can be used for cultivar improvement and decreased farming costs.
Identification of blast resistant sources -
US rice breeders have incorporated blast resistance genes Pi-ta and Pi-b from unadapted rice germplasm accessions into some recently released rice varieties, but new blast resistance genes need to be identified. The Dale Bumpers National Rice Research Center, in cooperation with the University of Arkansas, Rice Research and Extension Center, identified 94 blast-resistant rice accessions from approximately 1000 accessions. From the 94 resistant accessions, 32 had either the Pi-ta or Pi-b resistance gene based on DNA markers. These 32 accessions are potential sources of new blast resistance genes for US rice breeding programs.
C. Significant activities that support special target poplations:
5.Describe the major accomplishments over the life of the project, including their predicted or actual impact.
Since this is the first year of the project, the major accomplishments over the life of the project are the same as those in Question 4.
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?
Described DB NRRC mission to numerous visiting scientists and rice industry groups.
Hosted 50th Anniversary Celebration on November 3, 2003, to some 50 Arkansas industry leaders.
Hosted an Open House of the DB NRRC on July 21, 2004, for over 75 industry leaders, in which latest research results were showcased.
Participated in annual University of Arkansas Rice Field Day through presentations and posters.
7.List your most important publications in the popular press and presentations to organizations and articles written about your work.
News release of May 3, 2004, by Jim Core of ARS Information Staff, on New Rice Stock Adds Good Trait to Genetic Collection.
Rutger, J.N., Raboy, V., Moldenhauer, K.A., Bryant, R.J., Lee, F.N. 2004. Registration of KBNT lpal low phytic acid rice germplasm. Crop Science. 44:363.
Rutger, J.N., Moldenhauer, K.A., Gravois, K.A., Lee, F.N., Norman, R.J., Bryant, R.J. 2004. Registration of five induced semidwarf mutants of rice. Crop Science. 44:1496-1497.
Rutger, J.N., Bryant, R.J. 2004. Registration of aromatic se rice germplasm. Crop Science. 44:363-364.
Rutger, J.N., Moldenhauer, K.A., Gravois, K.A., Lee, F.N., Norman, R.J., Mcclung, A.M., Bryant, R.J. 2004. Registration of six semidwarf mutants of rice. Crop Science. 44:364-366.
Rutger, J.N., Bryant, R.J., Moldenhauer, K.A., Gibbons, J.W. 2004. Registration of goldhull low phytic acid (glpa) germplasm of rice. Crop Science. 44:1497-1498.
Rutger, J.N., Gibbons, J.W., Anders, M.M., Moldenhauer, K.A., Bryant, R.J. 2004. Registration of LGRU ef early flowering mutant of rice. Crop Science. 44:1498.
Yan, W., Rutger, J.N., Bockelman, H.E., Tai, T. 2003. Comparison of agronomic traits between the USDA-ARS rice collection and a core subset [abstract]. Annual Meeting Abstracts 2003. American Society of Agronomy. p. 229.
Yan, W., Rutger, J.N., Bryant, R.J., Lee, F.N., Gibbons, J.W. 2003. Characteristics of newly introduced accessions in the USDA-ARS rice quarantine program. Arkansas Agricultural Experiment Station Research Series 504. pp. 112-124.
Yan, W., Dilday, R.H., Helms, R.S., Bourland, F.M. 2004. Effects of gibberellic acid on rice germination and seedling emergence in stress conditions. Arkansas Agricultural Experiment Station Research Series 517. pp. 303-316.
Lee, F., Yan, W., Gibbons, J., Emerson, M.J., Clark, S.D. 2003. Rice blast and sheath blight evaluation results for newly introduced rice germplasm. Arkansas Agricultural Experiment Station Research Series 504. pp. 85-92.