1a.Objectives (from AD-416)
The objective of this work is to assess disease resistance in wheat accessions from the National Small Grains Collection to diseases of increasing importance in U.S. wheat production.
1b.Approach (from AD-416)
Key accessions from the NSGC are being genotyped using DArT marker technology and SSR markers. These materials will be tested at North Dakota State University for resistance to important wheat diseases including bacterial leaf streak, Stagonospora nodorum blotch, tan spot, and Septoria tritici blotch. An association genetics approach will be taken to search for relationships between markers and disease resistance. Disease resistance data will be reported to the Germplasm Resources Information Network for dissemination to the plant breeding community. Documents SCA with NDSU.
This project contributes to objective 2, Strategically evaluate (i.e. “phenotype”) small grains genetic resources for priority biotic and abiotic stress resistance, quality factors, and other priority agronomic traits, and incorporate phenotypic data into GRIN and/or other databases. A subset of winter wheat (n = 639) and spring wheat (n = 567) accessions from the National Small Grains Collection were evaluated for resistance to tan spot (races 1 and 5), Stagonospora nodorum blotch (SNB), and spot blotch at seedling stage while resistance to Septoria leaf blotch (STB) and bacterial leaf streak (BLS) was evaluated at flag leaf stage in the greenhouse at North Dakota State University. Among spring wheat accessions, 77, 121, 109, 83 and 183 accessions were resistant to tan spot races 1 and 5, spot blotch, SNB and BLS, respectively. These accessions were further analyzed with low density DArT markers and 836 markers were polymorphic across accessions. PCA analysis identified DArT markers linked to novel QTLs and will facilitate in introgression and marker-assisted-selection process. Likewise, several winter wheat accessions also were identified for potential sources of resistance to these leaf spot diseases and would be particularly useful for wheat breeding programs. Activities for this project are monitored through site visits, conference calls, and exchange of email.