Submitted to: Wheat Genetics International Symposium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/7/1998
Publication Date: N/A
Technical Abstract: Wheat scab, caused by Fusarium graminearum, is a destructive disease in wheat. To accelerate the development of scab resistant wheat cultivars, we identified DNA markers linked to a major quantitative trait locus (QTL) for scab resistance. Recombinant inbred lines (RILs) were derived by single-seed descent from a cross between the resistant wheat cultivar Ning 7840 and the susceptible cultivar Clark. The RILs were evaluated in the greenhouse as F7 and F10 families for resistance to spread of scab in spikes by injecting conidiaspores into a central floret. Scab symptoms were evaluated from 3 to 21 days after inoculation. DNA from the F9 RILs was digested with MseI and EcoRI restriction enzymes and analyzed for amplified fragment length polymorphisms (AFLPs). Bulks of DNA from susceptible and resistant RILs were analyzed with 208 primer combinations. Twenty combinations amplified at least one polymorphic band between two bulks. Nine AFLP markers showed significant association with scab resistance and individually explained 28% to 53% of the total variation (R2) in F7 and F10 families. These markers with high R2 values were in one linkage group. One QTL with a major effect for scab resistance was identified in the linkage group.