Stripe rust resistance in soft red winter wheat cultivars and lines

Stripe rust, caused by Puccinia striiformis f. sp.tritici, has emerged as an important disease of soft red winter wheat in the eastern region of the U.S. Identification of stripe rust resistance sources for the eastern U.S. is extremely important to determine the major and minor Yr genes involved.Breeding lines and cultivars from Universities and private companies (713 entries in 2006 and 380 entries in 2007) were evaluated in the field at Plains and Griffin, GA.Plots were inoculated with a local field culture of stripe rust.The races of stripe rust used for inoculation were collected in Georgia, identified and designated as PST 100 and 102 (Dr.X.M. Chen, Pullman, WA).Stripe rust infection type and percent severity data were assessed multiple times at each location.The results indicated that numerous cultivars and lines of soft red winter wheat possess the resistant gene Yr17 in their background.Other sources of seedling resistance were also identified in PIO26R61, Kinsco, and VA 270.A total of 102 lines from the field nursery were identified as having a level of resistance better than that of 'Pioneer 26R61'.From field evaluations and seedling screening, a number of lines with adult plant resistance were identified such as GA 951395-3A31 and GA 96693-4E16.Additional evaluations are proposed to identify other sources of adult plant resistance