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? The most critical problem facing the U.S. hop industry is the need for hop varieties that provide superior brewing quality and that contain resistance to two serious diseases, powdery and downy mildew. Although downy mildew has been a problem in U.S. hop producing regions for many years, powdery mildew disease was first identified in the U.S. in 1997. The increased costs associated with controlling this disease threaten the economic viability of the entire U.S. hop industry. Presently, the only way to control powdery mildew is by applying expensive fungicides as many as eight times per season. The costs of these applications can easily exceed the gross receipts for the crop. When this disease emerged in U.S. hop production fields, there were no resistant varieties in production and no understanding of genetic mechanisms that would contribute to disease resistance. Without significant and rapid progress in developing economic means to control the disease, U.S. hop production cannot remain economic and competitive in global hop markets, farm profitability will severely decline, and reliance of brewers on foreign hop imports will increase. It also is important to identify specific compounds in hop cones that contribute superior flavor and to develop varieties that produce enhanced levels of these compounds for commercial production. The objectives of this research are:. 1)Identify, sequence, map and characterize hop gene conferring specific phenotypic functions of economic importance.. 2)Characterize genetic diversity of hop accessions maintained in the USDA hop germplasm collection.. 3)Identify and develop hop germplasm possessing new and unique traits that have economic impact on the American hop industry. To solve these problems, both cultivated and wild hop germplasm are being evaluated for their potential use in development of new varieties, traditional plant breeding is being used to incorporate traits that provide disease resistance and superior brewing characteristics into new germplasm, and molecular markers are being developed to decrease the length of time required to develop new varieties. This research addresses objectives of National Programs #301, Plant, Microbial and Insect Germplasm, Conservation and Development-Germplasm Enhancement and Manipulation (70%) and #303, Plant Disease Host Plant Resistance to Disease (30%). This work is relevant to U.S. breweries, hop marketing companies and hop producers and critical to maintain U.S. leadership in hop production and export. 2.List the milestones (indicators of progress) from your Project Plan. This project replaced CRIS project 5358-21000-030-00D effective 3/10/2004 (Normal Progression) approved through the OSQR process. Year 1 (FY2003) Make Genomic Libraries Estimate Genetic diversity/ Publish results Make year 2003 Crosses Year 2 (FY2004) Run micro-satellites/Take field data-1st yr Collect second year data estimating heritability of specific traits Year 3 (FY2005) Finish sequencing genes/ analyze data for Objective 1 Finish micro-satellites/ 2nd year data collection Collect 1st year data and release superior germplasm from year 2001 crosses Year 4 (FY2006) Collect 2nd year data for Objective 2. Collect 2nd year data for Objective 3 Year 5 (FY2007) Release superior germplasm from year 2003 crosses 3.Milestones: A. The milestones addressed in FY 2004 are also detailed in the Final Annual Report for the previous project 5358-21000-030-00D which was terminated 3/9/2004 (Normal Progression). Milestones that were scheduled to be addressed in 2004: Run micro-satellites/Take field data-1st yr ' This milestone was completed albeit instead of using microsatellites we used AFLP due to inconsistent results with microsatellites and the need for more work on perfecting the technique in hop. Collect second year data estimating heritability of specific traits. This milestone was completed. Milestones I expect to address over the next 3 years (2005, 2006, and 2007): Year 3 (FY2005) Finish sequencing genes/ analyze data for Objective 1 Finish micro-satellites/ 2nd year data collection Collect 1st year data and release superior germplasm from year 2001 crosses Year 4 (FY2006) Collect 2nd year data for Objective 2. Collect 2nd year data for Objective 3 Year 5 (FY2007) Release superior germplasm from year 2003 crosses 4.What were the most significant accomplishments this past year? A. Single most significant accomplishment during FY2004 year: Techniques that could help hop breeders to eliminate corsses that would result in inbreeding depression are lacking. Scientists in the Forage Seed and Cereal Research Unit, Corvallis, OR. developed molecular marker technologies to identify significant correlations between genetic similarities and pedigree relatedness. The genetic similarities and pedigree relatedness between 19 economically important hop (female) varieties with each of 82 male experimental accessions using molecular markers were estimated. This information and the documented molecular procedure will enable hop breeders to make critical decisions regarding which males and females to use for germplasm and varietal development. B. Other significant accomplishments: The genetic diversity among 54 recently collected wild North American hop accessions was estimated. The importance of this accomplishment is that 'fingerprints' for each of these wild accessions can be used to determine their relatedness with known USDA hop clusters. Molecular markers identified by AFLP technology were used to differentiate 3 different clusters that were significantly correlated to the collection location. This new knowledge will permit the use of wild American hop accessions to broaden the gene pool of the USDA hop collection from its currently narrow base and increase our chances for possessing important genes for future pests or environmental conditions. Incorporation of powdery mildew resistance into commercial hop varieties is critical to the economic sustainability of northwest hop production. Scientists in the Forage Seed and Cereal Research Unit, Corvallis, OR. identified molecular markers that aid in the selection of breeding materials among seven near isogenic hop lines that differ primarily in their respective resistance to the seven known races of powdery mildew. Molecular markers unique to a single genotype that represent potential markers to select for powdery mildew resistance were identified. If these markers are correlated with resistance, they will provide a means of seedling selection for powdery mildew resistance, a measure that would significantly speed development of disease resistant varieties. Twenty two unique AFLP bands that appear to be highly correlated with downy mildew resistance in hop were identified. This is important because this is the first time a relationship between specific molecular markers and downy mildew resistance in hop has been demonstrated. Quantitative trait loci (QTL) analyses were used to identify these markers. If these markers prove to be correlated with field resistance, they will provide a new means to select for resistance to downy mildew, a desirable trait that has been particularly difficult to identify. C. Significant activities that support special target populations: None D. Progress Report Opportunities to submit additional programmatic information: None 5.Describe the major accomplishments over the life of the project, including their predicted or actual impact. This project replaced CRIS project 5358-21000-030-00D effective 3/10/2004 (Normal Progression) approved through the OSQR process. Major accomplishments over the life of the project are included here for continuity. The genetic diversity of male and female accessions contained in the USDA-ARS hop germplasm collection has been characterized and crosses to take advantage of this diversity are planned. These crosses will provide both short- and long-term benefits to the U.S. hop industry. In addition, plant exploration trips have identified wild North American hop accessions that have been incorporated into the collection. Some of these offer potentially new sources of resistance to fungal and insect pests. The genetic diversity amongst these wild North American hop accessions has been determined. Powdery mildew (PM) and downy mildew (DM) resistant hops have been identified and used to develop resistant plants with superior field production and brewing quality traits. The USDA-21736 experimental line was selected for superior resistance to all races of PM AND DM found in Oregon and Washington. USDA-21736 also exhibited higher levels of total bittering acids and yielded more than any other public variety. This accession was released in 2002 as a new variety named 'Newport'. We also released five other varieties and a new germplasm. Two new accessions are being investigated at the commercial level for potential brewery use. Crosses have been made that were designed to incorporate resistance to 3 different races of powdery mildew. The manner in which bittering and other flavor compounds important to the brewing industry are inherited have been determined and used to select superior genetic lines with acceptable yield and powdery mildew resistance. We also cloned hop fungal chitinases and glucanases genes we believe are involved in powdery mildew resistance, and have identified numerous molecular markers that will prove useful for identifying new sources of powdery mildew AND downy mildew resistance and genetic diversity in world hop varieties. Hop genetic improvement by this project has helped the USA become the largest producer and world exporter of hops. 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? Hop research program tours were presented to representatives of Anheuser Busch and Miller Brewing Companies, Hop Growers of America and individual hop producers that included discussions about the integrated USDA-ARS greenhouse, field, chemistry analysis and molecular biology research approach in Oregon. Participants in the International Humulus Symposium, held in Corvallis during August 2004, were given a tour of the USDA-ARS Molecular Biology lab, the Chemistry lab and the Hop Field research station. Participated in field tours for the Washington Hop Commission and Oregon Hop Commission and presented a lecture on hop production to students at Oregon State University in the Introductory Brewing Science course. 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. Gave oral or poster presentations to the following organizations: Hop Research Council (August, 2004) International Soc. for Hort. Science International Humulus Symposium (August, 2004)