2010 Annual Report 1a.Objectives (from AD-416) Conduct a two year multi-location association mapping study to develop marker-trait associations to facilitate the development of new oat varieties with superior crown rust resistance. 1b.Approach (from AD-416) Single row plots for all spring and CORE association lines will be grown in randomized complete block design with two replications. Disease severity data based on reactions to field isolates will be collected at the appropriate time. All data will be collected and analyzed for marker trait associations. Documents Grant with University of Wisconsin. 3.Progress Report The 685 oat population developed under the USDA NIFA AFRI agreement 5366-21000-028-11R and North American Millers’ Association trust agreement 5366-21000-028-18T was planted in Madison, WI. The population was grown under natural crown rust disease pressure and disease reactions were collected for all 685 lines. Communication and exchange of work has taken place via meetings. The project is funded through a reimbursable agreement with USDA NIFA AFRI and North American Millers’ Association trust.