Submitted to: Wheat Newsletter
Publication Type: Other
Publication Acceptance Date: 1/2/2001
Publication Date: N/A
Technical Abstract: Stem rust caused little damage to wheat in the U.S. in 2000, although the amount of rust in the central and northern plains was higher in 1999 and 2000 than in other recent years. Wheat leaf rust caused an estimated loss of 30 million bushels of wheat in the U.S. in 2000, which is less than average losses in the last 15 years. Losses to leaf rust were 2.9% in Kansas and 4% for winter wheat and 3% for spring wheat in South Dakota in 2000. Wheat stripe rust was unusually common in the Great Plains in 2000; it caused 7% loss in Arkansas with lower losses in adjacent states. The cooler than normal spring and early summer favored stripe rust development. Stem rust races QCMS and RCMS were common in the U.S. with QCCJ somewhat less so in 2000. Wheat leaf rust races MCRK and TLGF were most common in the Southeast, and races MBDS and MCDS were most common in the Great Plains. The virulence combination overcoming resistance genes Lr9 and Lr10 increased in the T races found in the Southeast in 2000. Previously this virulence combination was rarely seen.