Location: Small Grains and Potato Germplasm Research
Project Number: 2050-21000-038-031-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2026
End Date: Aug 31, 2028
Objective:
This project will identify new sources of genetic resistance to yellow dwarf virus (YDV) infection in oat and barley accessions held by the National Small Grains Collection and to map QTL for utilization in oat and barley breeding programs.
Approach:
The National Small Grains Collection (NSGC) holds over 24,000 oats and 36,000 barley accessions, including both cultivated and their wild relatives. Un-tapped genetic variation within these accessions has the potential to provide oat and barley cultivars with new genetic resistance to diseases, including the economically important YDV disease caused by the virus barley yellow dwarf virus (BYDV) on both crop species. This project will evaluate accessions of Avena spp. and Hordeum spp. in the NSGC identified by the ARS PI as potentially un-tapped based on their history of disease screening and utilization in oat and barley breeding. Resistance to yellow dwarf virus will be scored under field conditions Dr. Juan Arbelaez Velez at the University of Illinois, serving as the Cooperator on this project. Field trials with 600 to 800 hill plots per year will be artificially infested with the BYDV vector (aphids) reared in a lab by the cooperator. Accessions identified as resistant to moderately resistant will be used as parents by the ARS PI in intra- or inter-specific crossing programs. Techniques for crossing the resistance-donor parent with agronomically adapted parents will vary depending on species and may include traditional cross-pollination, embryo rescue and colchicine doubling. The University Cooperator will deliver single-plant descent seeds of accessions selected as resistant and moderately resistant to the ARS PI for population development. The ARS PI will evaluate the resulting populations for agronomic performance under field growing conditions, and the University Cooperator will evaluate them for BYDV resistance. The ARS PI and University Cooperator will collaborate in mapping disease resistance genes. Characterization and mapping of YDV resistance identified in the NSGC will ensure that the resistance deployed into subsequently released germplasm is both novel and effective.