Genome-Wide Association Analysis and Candidate Gene Prediction of Wheat Wet Gluten Content

The wet gluten content (WGC) of wheat is a key indicator of wheat-processing quality, and its genetic basis is extremely critical in breeding. This study evaluated the WGC of 207 wheat accessions under three growing seasons from a natural population. Nine quantitative trait loci (QTLs) explained 7.61-15.18% of phenotypic variation in a genome-wide association study (GWAS) using a 660K SNP array. Among them, qWGC6B.2 on chromosome 6BL was consistently detected across multiple environments, accounting for 10.08-12.27% of variation. Incorporating grain transcriptome data led to the identification of TaWGC6B.1 (TraesCS6B02G386700), which is highly expressed in developing endosperm and strongly correlated with WGC. A competitive allele specific PCR (KASP) marker development and validation indicated that the Whaas68366_GG allele significantly enhanced gene expression and WGC. This study identified key genes and molecular markers, providing theoretical and technical support for WGC genetic improvement in wheat (Triticum aestivum L.).