Abstract
Simultaneously improving Fusarium head blight (FHB) resistance and grain yield is challenging in wheat breeding. The correlations between spikelet compactness (SC), grain number per spike (GNS), thousand-grain weight (TGW) and FHB resistance remains unclear in common wheat. Identification of major quantitative trait loci (QTL) conferring FHB resistance and yield components, and development of breeder-friendly markers for the QTL are prerequisites for marker-assisted selection (MAS). Here, a recombinant inbred line (RIL) population derived from a cross between a resistant cultivar Yangmai 12 (YM12) and a susceptible cultivar Yanzhan 1 (YZ1) was used to map QTL for FHB resistance and yield components. A total of 22 QTL were identified; among these, six are likely to be new for corresponding traits. A QTL cluster (Qclu.yas-2D) for FHB type Ⅱ resistance, SC, GNS, and TGW was detected on chromosome 2D. Breeder-friendly kompetitive allele-specific PCR (KASP) markers flanking the interval of Qclu.yas-2D were developed and validated in a diverse panel of 166 wheat cultivars and advanced lines. The YM12 alleles of Qclu.yas-2D significantly increased FHB resistance, SC, and GNS but decreased TGW in the validation population. The KASP markers developed for Qclu.yas-2D have great potential for breeding high-yielding wheat cultivars with enhanced FHB resistance.
