QTL mapping for Type II resistance to Fusarium head blight and spike architecture traits in bread wheat

Abstract

In breeding for resistance to Fusarium head blight (FHB) there should be precise differentiation between QTL for resistance and those for spike architecture traits that indirectly affect disease. QTL mapping for FHB Type II resistance and spike architecture traits was carried out in a population of 80 RIL. Three QTL for FHB Type II resistance were identified respectively on chromosomes 2A, 4A and 6D, the last of which is reported here for the first time. The number of florets per spike and per spikelet was associated with FHB Type II resistance but there was not co-localization between QTL for these traits. However, QTL for number of spikelets per spike overlapped with those for FHB Type II resistance on chromosomes 2A and 6D. Spike architecture traits-notably, the number of florets per spike and per spikelet-should be considered in the design of breeding strategies to increase Type II resistance to FHB in bread wheat.