Genetic polymorphism of high molecular weight glutenin subunits of ancient and modern Argentinean bread wheat (Triticum aestivum L.) cultivars and its relationship with quality.

Abstract

Bread wheat quality is largely determined by genotype (G), particularly the combination of glutenins and gliadins, and in turn, is affected by the environment (E) and the GxE interaction. In Argentina, wheat cultivars are classified into different quality groups (QG) according to their baking aptitude. Knowing the combination of high molecular weight glutenin subunits (HMW-Gs) would be a good tool for choosing the genotype. In this research, 135 bread wheat cultivars released between 1980 and 2020 were analyzed using one-dimensional gels obtained by SDS-PAGE. Great genetic diversity was found among the HMW-Gs alleles, particularly in the Glu-B1 locus, even within the same quality groups. Furthermore, it was found that modern genotypes have alleles associated with better industrial quality according to the Glu-1 Score. However, in the last decade analyzed, most of the genotypes did not present the subunit 7 overexpressed which is related to quality improvements (7 + 8* subunits). In addition, the gliadin patterns more frequently observed in recently released varieties are not related to good baking quality. Being able to know the quality of gluten proteins, even within each quality group, could constitute a contribution to agronomic management practices that do not imply an extra cost.