Allelic variation of HMW glutenin subunits of Ethiopian bread wheat cultivars and their quality

Abstract

High molecular weight glutenins are often effective in identifying wheat (Triticum aestivum) genotypes with good baking quality. The high molecular weight glutenin subunit composition of Ethiopian cultivars and advanced lines was investigated to determine their influence on quality. Three alleles at Glu-A1, five at Glu-B1 and two at Glu-D1 and eleven different banding patterns were identified. Few cultivars had biotypes at Glu-A1 and Glu-D1 loci. There were highly significant differences between genotypes and banding patterns for the SDS-sedimentation test, mixograph development time, alveograph strength and loaf volume; but not for protein content. The frequency of subunits 5+10 among genotypes was 73%. The accumulation of high scoring alleles in our germplasm was without deliberate selection pressure towards high Glu-1 scoring alleles during breeding. Introductions from CIMMYT are widely used and such materials might have gone through selection and accumulation of such alleles at CIMMYT. Most of the studied materials had the required subunits of high quality scores and better values of the quality traits than originally thought. Therefore, the concern about poor baking quality is unlikely to be due to Glu-1 allelic variations alone.Key Words: Allelic variation, grain quality, HMW glutenins RÉSUMÉLe poids moléculaire élevé des glutanines est souvent un moyen efficace pour identifier les génotypes du blé (Triticum aestivum) doté de bonnes qualités patissières. Une investigation était faite sur le poids moléculaire élevé des glutanines des sous unités des cultivars éthiopiens ainsi que sur des lignées avancées pour déterminer leur influence sur la qualité. Trois allèles à Glu-A1, cinq à Glu-B1 et deux à Glu-D1 ainsi que onze différents modes de bandage étaient identifiés. Peu de cultivars avaient des biotypes à Glu-A1 et Glu-D1 loci. Une différence hautement significative était observée entre génotypes et modes de bandage pour le test de sédimentation SDS, le temps de développement de mixographe, la force de l'alvéographe et le volume du pain mais non au contenu en protéines. La fréquence des sous unités 5+10 parmi les génotypes était 73%. L'accumulation des allèles à score plus élevé dans notre germoplasme avait eu lieu sans sélection délibérée de la pression des allèles à score plus élevé en Glu-1 pendant le breeding. Des introductions de CIMMYT sont largement utilisées et de tels matériels devraient passer par la sélection et l'accumulation de telles allèles au CIMMYT. La plupart des matériels étudiés possédaient de sous unités requises avec de scores de haute qualité et meilleures valeurs de traits de qualité qu'on ne le pensait originellement. Par conséquent, le problème concernant la pauvre qualité patissière n'était pas seulement dû aux variations alléliques Glu-1.

Genetic divergence for high-molecular weight glutenin subunits (HMW-GS) in indigenous landraces and commercial cultivars of bread wheat of Pakistan

“…These results were in agreement with our studies; however, allele 2**+12ꞌ was not present in our germplasm. A large number of rare alleles was reported, which were confirmed by the findings of Branlard (2003), Tabasum (2011), andDessalegn (2011). Several novel HMW-GS alleles, such as 7*, 7**, 8*, and 8** (Liu et al, 2007), were detected in the present study and have also been detected in Chinese wheat landraces.…”

Allelic variations of glutenin subunits and their associationwith quality traits in bread wheat genotypes

“…Therefore, one of the main objectives of the Turkish bread wheat breeding program is to develop wheat varieties with higher grain yield (GY) and better bread-making qualities in terms of protein and gluten content (Baloch et al, 2017). In this process, it is important to consider and evaluate genotypes, environments, and their interaction as the main factors affecting wheat quality traits.The quality of bread-making is mainly related to the composition of endosperm storage proteins, namely gliadins and glutenins (Dessalegn et al, 2011). Gliadins are monomeric proteins synthesized by the Gli-1 and Gli-2 loci, which are located on the short arms of homoeologous chromosomes (He et al, 2005).…”

“…The quality of bread-making is mainly related to the composition of endosperm storage proteins, namely gliadins and glutenins (Dessalegn et al, 2011). Gliadins are monomeric proteins synthesized by the Gli-1 and Gli-2 loci, which are located on the short arms of homoeologous chromosomes .…”

Glu-A3 and Glu-B3 Alleles for LMW Protein in Local Wheat Identification of Glu-A3 and Glu-B3 Alleles for LMW Protein Subunits in Some Wheat Genotypes of Pakistan

“…Glutenin possess the rheological characteristics that are vital for a wide range of food products (He et al, 2005;Shewry et al, 1995). End use quality of wheat is influenced by the composition of storage proteins (Dessalegn et al, 2011), its quality and quantity confers elasticity and extensibility necessary for bread making. It contributes 80-85% of the total flour protein (Shewry et al, 1995).…”