1a. Objectives (from AD-416):
Introgress BYDV tolerance and resistance genes into oat genetic backgrounds and develop DNA markers linked to these tolerance/resistance loci to facilitate oat breeding.
1b. Approach (from AD-416):
Utilize standard breeding practices, and molecular marker technology to develop oat lines with enhanced resistance/tolerance to BYDV.
3. Progress Report:
The overall goal of this project has been to generate oat varieties with improved resistance to barley yellow dwarf virus. This has been accomplished through a very active breeding effort involving a wide range of oat germplasm, including material from the University of Illinois, North Dakota, South Dakota, Minnesota, Wisconsin, Louisiana, North Carolina and Saskatchewan, as well as entries from the Uniform Early Oat Nursery, the Cooperative Partial Rust Nursery, the SunOat Nursery and the Uniform Winter Oat Nursery. Each year during the project phenotypic data on barley yellow dwarf virus (BYDV) tolerance were collected on several thousand hill plots. This effort has led to the following significant accomplishments: In the 2012 season phenotypic data were collected on barley yellow dwarf virus (BYDV) tolerance for several thousand hill plots. Two replications of hills were planted, inoculated with PAV-IL and evaluated for BYDV symptoms. Breeding lines from Wisconsin, South Dakota, Minnesota, Louisiana, North Carolina, Saskatchewan, and other programs were evaluated for BYDV tolerance in 2012. Lines from the Uniform Early Oat Nursery, the Uniform Midseason Oat Nursery, the Cooperative Partial Crown Rust Resistance Nursery, the SunOat Nursery and the Uniform Winter Oat nursery were evaluated in 2012. Molecular marker data were obtained for the two RIL populations that were previously evaluated phenotypically for BYDV tolerance. The objective of this project is to identify markers that are linked to quantitative trait loci for Barley Yellow Dwarf Virus tolerance in two bi-parental recombinant inbred populations. The two populations are BYDV tolerant x BYDV susceptible crosses. One population is 122 lines (Clintland 64 / IL86-1156) and the second population is 184 lines (Clintland 64 x IL86-5698). About 1000 Single Nucleotide Polymorphisms (SNPs) which were polymorphic between the two parents in each population were used for Quantitative Trait Loci (QTL) analysis. QTLs with significant effects were identified on chromosomes 3C and 19A with possible QTL with smaller effects on several other chromosomes. Additional analysis of the data needs to be done. A subset of the markers identified can be used to better select parents for improvement of BYDV tolerance. The association of a significant number of molecular markers with QTL for BYDV tolerance in oat is an important accomplishment and represents a significant step forward in using molecular markers to improve BYDV tolerance in oat. Additionally, two methods of evaluating BYDV tolerance in oats and wheat were compared. Data was collected on a set of replicated hill plots of both wheat and oats to compare the effectiveness of BYDV tolerance evaluations using the following methods: 0-9 visual scoring, measurement of percentage of stunting based on reduction in height in inoculated hills compared to control hills; and percentage of stunting based on comparison of total above ground biomass produced by inoculated hills compared to control hills. This work has impact on several strategies for oat improvement. The phenotypic data on breeding lines from a number of breeding programs are valuable contributions that enhance the selection for BYDV tolerance in spring and winter oats in a number of breeding programs including the University of Illinois breeding program. These data are invaluable in the development of oat varieties with enhanced levels of BYDV tolerance. The data generated for the RIL populations are valuable for studying the inheritance of BYDV tolerance and the location of loci controlling BYDV tolerance in oat.