Beta-Amylase Isozymes in Spring Common Wheat and Their Role in the Aggregation of Grain Proteins

Abstract

The polymorphism of beta-amylase isoenzymes in spring common wheat was studied among varieties cultivated under the conditions of the Northern Trans-Urals. Four zymotypes were identified among the 41 accessions. A, C, and A* isozymes differed most frequently, the share of which, respectively, was 64.6 ± 7.3, 22.0 ± 3.7, and 12.2 ± 3.7%. During 2011–2013, the aggregating ability of grain proteins was studied using -S-S-bonds between groups of varieties carrying variants of beta-amylase A and C. It was established that the presence of isoenzyme C promoted a greater aggregation of grain polypeptides in comparison with beta-amylase A carriers but did not affect the formation of yield. Differences in beta-amylase did not affect the falling number associated with amylase activity.