QTL mapping of fusarium head blight resistance in winter wheat cultivars ‘art’ and ‘everest’

Fusarium head blight (FHB) is a disease of small grains most commonly associated with the fungal pathogen Fusarium graminearum. Development and deployment of resistant cultivars has proved to be an effective method to combat the disease; however, the majority of major resistance has historically been found in exotic material. Transferring resistance from these sources into locally adapted cultivars has been a slow process due to linkage drag. Therefore, it is important for breeders to search for sources of resistance in native material. This study was conducted to identify quantitative trait loci (QTL) for resistance to spread of FHB within the spike (Type II resistance), accumulation of deoxynivalenol toxin in grain (Type III resistance), and resistance to kernel infection (Type IV resistance) using a doubled-haploid population developed from a cross between the hard red winter wheat (Triticum aestivum L.) cultivars Art and Everest. Four QTL conferring resistance to FHB traits were detected on chromosomes 2D, 4B, and 4D. Qfhb.ksu-2D, located on the short arm of 2D, is located near the major photoperiod gene Ppd-D1 and was associated with all three FHB traits. Qfhb.ksu-2D.1 is on the long arm of 2D and was associated with percentage symptomatic spikelets (PSS). The QTL on chromosomes 4B and 4D were associated with PSS and overlapped with the major height genes Rht-B1 and Rht-D1, respectively. In this study, the haplotype analysis for Ppd-D1 showed significant associations between the photoperiod-sensitive allele Ppd-D1b and lower levels of all three FHB traits. The haplotype analysis for the Rht-B1 and Rht-D1 loci showed significant associations between the dwarfing alleles and increased resistance to PSS.