We applied DNA-based marker-assisted selection to introduce the rare Glu-A1t allele into winter bread wheat (Triticum aestivum) and provided the first validation of the Glu-A1t DNA markers for varieties adapted to Northern European conditions. The allele has earlier only been screened in spring wheat using protein analysis. The Glu-A1t allele encodes a unique pair of high molecular weight glutenin subunits (HMW-GSs), with both A1x21* and A1y21* being expressed. This allele has shown potential for improving bread-making quality and increasing grain protein content in bread wheat. Four molecular markers (the indel marker Xid3, the STS marker Axnull, and two KASP markers Mk-A1-1-12 and Mk-A1-1-13) were validated for their ability to detect Glu-A1t and distinguish it from other GLU-A1 alleles (a, b, c). These markers were used for creating hybrid winter wheat lines, which can be used for evaluating the effects of Glu-A1t on yield and baking quality. Genotyping results were fully consistent with SDS-PAGE analysis of HMW-GS composition, confirming the presence of both A1x21* and A1y21* subunits in F3 hybrids. Overall, this study delivers a novel set of validated molecular tools and genetic resources that can be directly applied in breeding programs aimed at improving wheat baking quality in Northern Europe.
Tikhonova et al. (Mon,) studied this question.