2003 Annual Report 4.What were the most significant accomplishments this past year? D. Progress Report This report serves to document research conducted under a Specific Cooperative agreement between ARS and the University of California, Davis. Additional details of research can be found in the report for the parent project, 5366-21000-022-00D, 'Small Grains Genetic Resource Management'. One thousand NSGC barley accessions were evaluated for barley stripe rust (BSR) reaction. BSR first appeared in late February in the nursery at Davis on a few very susceptible entries and reached high levels on many susceptible entries by late April. The spreader Max was severely diseased by early May. At the time of the final BSR severity rating (May 12-14), about 14% of the NSGC accessions had a 50-100S reaction. About 50% of the NSGC accessions (including a high proportion of lines from Ethiopia) remained BSR-free. BYD, leaf rust, powdery mildew, net blotch and scald also occurred in the nursery; entries with severe levels of these diseases were noted. Among the NSGC accessions, 137 lines had severe BYD; 106, severe leaf rust; 36, severe powdery mildew; 4, severe net blotch; and 13, severe scald. Among the cooperator lines, 93 lines had severe BYD; 7, severe leaf rust; 47, severe powdery mildew; 30, severe net blotch; and 50, severe scald.