Genetic polymorphism of glutenin subunits with high molecular weight and their role in grain and dough qualities of spring bread wheat (Triticum aestivum L.) from Northern Kazakhstan

High-molecular weight glutenin (HMWG) subunits are an important component of the gluten protein complex in cereal grains and can influence the baking properties of wheat. The study of polymorphism of glutenin makes it possible to isolate preferred genotypes with higher grain quality. To determine the allelic state of the Glu-1 loci controlling HMWG in 122 spring bread wheat varieties from Northern Kazakhstan, an SDS-based analysis was performed. The highest frequencies (in percentage) were detected in the alleles Glu-A1b (56.1), Glu-A1c (42.4), Glu-B1c (85.0), Glu-D1a (50.6) and Glu-D1d (46.9). A technological and baking evaluation of 33 varieties and 40 prospective selection lines on samples of bread wheat with known allelic compositions at the Glu-1 loci was carried out. Associations between HMWG and several technological traits were established: component 2* (allele Glu-A1b) with gluten content and P/L ratio; 7 + 9 components (allele Glu-B1c) with valorimetric index; and components 2 + 12 (allele Glu-D1a) with the ratio P/L. In some cases, discrepancies between the predicted baking qualities based on HMWG subunits and the results of traditional technological and baking evaluations have been revealed.