Genome-Wide Association Study and QTL Mapping Revealed Genetic Loci for Fusarium Head Blight Resistance in Chinese Hexaploid Wheat
Abstract Fusarium Head Blight (FHB) greatly affects wheat yield worldwide and could also downgrade quality. In this study, a total of 406 wheat cultivars were investigated for FHB disease index (DI). Results indicated that the FHB DI of 95% of the tested cultivars showed more than scale 2. Genome-wide association study (GWAS) identified 321 SNPs significantly related to FHB resistance on all chromosomes with 2.71–13.32% phenotypic variance explained (PVE). An important genetic locus gFHB-5A (329,828,930 to 595,372,995 bp) was identified to modulate FHB resistance in two panels, and the incidence of resistant alleles at the gFHB-5A1a locus were increasing with time in the tested cultivars. Two loci of gFHB-2B (9,740,162 to 68,200,954 bp) with PVE values of 2.73–3.57% and gFHB-7A (515,126,041 to 537,557,064 bp) with PVE values of 2.71–7.04% were identified to be significantly associated with FHB resistance. Linkage analysis in a bi-parental population identified the QTL FHB.hau-4D flanked by markers wPt-8836 and wPt-4572 with PVE value of 8.9%. This study identified new genetic loci to control FHB resistance and provided useful information of marker-assist selection in wheat FHB resistance breeding.
