Fusarium head blight (FHB) is a devastating disease that threatens wheat production worldwide, and using genetic resistance is one of the most effective approaches to combat FHB. Plant heading date (HD) has often been associated with FHB resistance. To identify quantitative trait loci (QTLs) for the FHB resistance and HD, an F8 recombinant inbred line (RIL) population derived from the cross G97252W x G97380A was evaluated for the two traits in two field trials and genotyped by genotyping-by-sequencing (GBS) markers. Both parents are hard winter wheat, but G97252W showed higher FHB resistance (moderate FHB resistance) and later heading date than G97380A (FHB susceptible). Single nucleotide polymorphism (SNP) markers generated by GBS in the same map positions were binned to identify unique SNPs for map construction and the resulting genetic linkage map consists of 38 linkage groups. The map was constructed with 586 SNP bin markers covering 2,131 cM genetic map with a marker density of 3.6 markers per cM. The RIL population was evaluated for percentage of symptomatic spikelet in a spike (PSS), Fusarium damaged kernel (FDK) and deoxynivalenol (DON) in the two field experiments. QTL mapping using the SNP bin map and FHB trait data identified a cluster of QTLs between 86.5 to 97.5 cM on chromosome 2D that explained 17.7%, 38.9%, 45.1% of the phenotypic variation for PSS, FDK and DON, respectively. Three QTLs for HD were detected on chromosomes 2A, 2D and 7D and explained 4.7%, 63.9% and 6.5% of the phenotypic variation, respectively. The 2D QTL for HD completely overlapped with the QTLs for the three FHB traits, suggesting these QTLs may be tightly linked or have pleiotropic effects on the four traits. Significantly positive correlations were also observed among the three FHB traits and HD (P < 0.01). These results implied that the 2DS QTL region may play a significant role in both FHB resistance and HD in the population.
ACKNOWLEDGEMENT AND DISCLAIMER
This material is based upon work supported by the U.S. Department of Agriculture. This is a cooperative project with the U.S. Wheat & Barley Scab Initiative. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.