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

TL;DR

This study identifies genetic factors influencing wheat gluten content, offering tools to improve wheat quality through breeding.

Contribution

The study discovers a key gene and molecular marker linked to wheat wet gluten content using genome-wide and transcriptome analyses.

Findings

Nine QTLs were identified, with qWGC6B.2 showing consistent effects across environments.

TaWGC6B.1 was found to be highly expressed in developing endosperm and correlated with wet gluten content.

The Whaas68366_GG allele was shown to enhance gene expression and wet gluten content.

Abstract

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.).

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