Two New Races of Wheat Leaf Rust in Southern Idaho. Larry J. Smith, Plant Pathologist, Education Administration, U.S. Department of Agriculture, Aberdeen, ID 83210. D. W. Sunderman, Research Leader, Agricultural Research, Science and Education Administration, U.S. Department of Agriculture, Aberdeen, ID 83210. Plant Dis. 64:324-325. Accepted for publication 29 October 1979. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1980. DOI: 10.1094/PD-64-324.

Two virulent biotypes of wheat leaf rust in southeastern Idaho were identified as new races. The races, designated UN 6 and UN 13, were isolated from and are virulent on the formerly resistant cultivar Dirkwin.