Quantitative Trait Loci for Fusarium Head Blight Resistance in U.S. Hard Winter Wheat Cultivar Heyne

Abstract

ABSTRACTFusarium head blight (FHB), mainly caused by Fusarium graminearum Schwabe, is a destructive disease that can significantly reduce grain yield and quality. Quantitative trait loci (QTL) for FHB type II resistance have been identified in many Chinese cultivars and other sources but have not been reported in U.S. hard winter wheat (HWW) (Triticum aestivum L.) to date. ‘Heyne’ is a Kansas HWW with moderate type II resistance to FHB. In this study, recombinant inbred lines (RILs) derived from ‘Trego’ × Heyne were evaluated for FHB resistance by single‐floret inoculation in two field and three greenhouse experiments from 2009 to 2011. Percentage of symptomatic spikelets (PSS) in an inoculated spike was scored 18 d (in the greenhouse) and 21 d (in the field) postinoculation. A total of 209 polymorphic simple sequence repeats (SSRs) were used to screen the RILs. Three major QTL on chromosomes 3AS, 4DL, and 4AL were associated with FHB resistance. The QTL on 3AS was flanked by Xgwm5 and Xwmc428 and explained up to 17.9% of phenotypic variation. Another QTL on 4DL near Xwmc720 explained 13.8 to 23.4% of phenotypic variation. The third QTL on 4AL was flanked by Xwmc219 and Xgwm160 and explained up to 18.1% of the phenotypic variation. Heyne contributed all resistance alleles of three QTL, and these QTL were designated as Qfhb.hwwg‐3AS, Qfhb.hwwg‐4DL, and Qfhb.hwwg‐4AL. These QTL can be used for improving FHB resistance in U.S. HWW by pyramiding them with Fhb1 or other major resistance QTL from Asian sources.