# Genetic Diversity of Prolamin Loci Related to Grain Quality in Durum Wheat (Triticum durum Desf.) in Kazakhstan

## TL;DR

This study explores the genetic diversity of prolamin loci in durum wheat from Kazakhstan and how they affect grain and gluten quality.

## Contribution

The study identifies novel associations between specific gliadin and glutenin alleles and gluten quality traits in Kazakhstani durum wheat.

## Key findings

- The γ45 gliadin component and Glu-A3a allele are positively linked to improved gluten quality traits.
- Distinct prolamin profiles are observed in wheat accessions from different ecological and geographical regions.
- Kazakhstani durum wheat genotypes show unique genetic diversity compared to global collections.

## Abstract

The technological properties of durum wheat grain are determined by prolamins (gliadins and glutenins). Information on the allelic composition of key loci remains incomplete despite existing global studies examining prolamin variability. This highlighted the need to study these traits in durum wheat in Kazakhstan. The effects of specific gliadin components with high- and low-molecular-weight glutenin fractions on gluten quality are also not fully clarified. This study aimed to characterise allelic diversity at prolamin-coding loci and evaluate associated grain quality traits. Using native and denaturing SDS-electrophoresis, 181 tetraploid wheat accessions from Kazakhstan, an International germplasm collection, and 26 breeding lines were analysed for allelic variation and associations with protein content, gluten content, gluten index, and SDS-sedimentation. The γ45 gliadin component and Glu-A3a allele were positively associated with SDS-sedimentation and gluten index, while Glu-B3b had a negative effect. Distinct prolamin profiles were observed among accessions from different ecological and geographical locations. These results support the selection of superior durum wheat genotypes and enable the identification of favourable allele combinations at the Gli-1, Gli-2, Glu-1, and Glu-3 loci in cultivars from Kazakhstan. Comparison with global tetraploid wheat germplasm collections demonstrates unique genetic diversity in genotypes, providing a valuable basis for breeding programs aimed at improving grain and gluten quality in durum wheat in Kazakhstan and Central Asian countries.