These lines involve three different resistant sources and three adapted cultivars, Morex, Crystal and Targhee, and will be evaluated both for agronomics and malting quality. Another 18 BC3F1 populations were screened, resistant plants increased and BC3F2 progeny screened again, with 100 resistant BC3F2 identified and transplanted for increase this spring in Stillwater and Aberdeen. Eleven BC3F2 populations were screened and 100 resistant plants transplanted for increase in Stillwater in the spring of 1997. These 29 populations involve eight cultivars and 23 different resistant lines. Nine BC3F1 populations were screened and resistant seedlings transplanted in the greenhouse in Stillwater for increase in the spring of 1997.
Analysis is on going.
All eight lines have shown multiple gene control for RWA resistance. Seventy-three crosses between homozygous resistant F3 lines and a susceptible were made in an attempt to isolate a single dominant gene for resistance. Genetic diversity studies are planned for resistant lines to determine if these lines carry different genes for resistance. This type of analysis requires three years for development of seed necessary for each test. One F1 and 19 testcrosses of a resistant x resistant F1 on a susceptible were made and 18 TC1F1 populations were increased to TC1F2 for future genetic diversity studies.