Identification of genetic loci and candidate genes underlying sharp eyespot resistance in wheat

QSes-7AL is the first major QTL for sharp eyespot resistance identified on wheat chromosome 7AL. The putative candidate gene TaPrx1L-7A was identified and preliminarily validated through integrated multi-omics data and molecular biology approaches. Wheat sharp eyespot is a soilborne disease caused by the necrotrophic fungal pathogen Rhizoctonia cerealis and is a major threat to wheat yield and quality worldwide. In this study, a novel major quantitative trait locus (QTL) for sharp eyespot resistance, designated QSes-7AL, was identified on chromosome 7AL (496.041-499.622 Mb) though analysis of a recombinant inbred line (RIL) population derived from a cross between H63-4 and Yangmai 158, using bulked segregant analysis (BSA), the wheat 660K SNP array, simple sequence repeat (SSR) markers, and kompetitive allele-specific PCR (KASP) markers. A peroxidase-encoding gene, TaPrx1L-7A, was identified as the most likely candidate gene for QSes-7AL based on integrated multi-omics data, gene function annotation, and expression pattern analysis. In addition, the gene was further validated as a strong candidate for QSes-7AL through diagnostic molecular marker, barley stripe mosaic virus-induced gene silencing (BSMV-VIGS), analysis of defense-related gene expression, and measurement of physiological indicators. Overall, these findings provide new insights into the molecular mechanisms underlying wheat resistance to sharp eyespot and offer a theoretical foundation for breeding resistant wheat varieties.