Allelic variation and genetic diversity of HMW glutenin subunits in Chinese wheat (<i>Triticum aestivum</i> L.) landraces and commercial cultivars

Abstract

Wheat landraces have abundant genetic variation at the Glu-1 loci, which is desirable germplasms for genetic enhancement of modern wheat varieties, especially for quality improvement. In the current study, we analyzed the allelic variations of the Glu-1 loci of 597 landraces and 926 commercial wheat varieties from the four major wheat-growing regions in China using SDS-PAGE. As results, alleles Null, 7+8, and 2+12 were the dominant HMW-GSs in wheat landraces. Compared to landraces, the commercial varieties contain higher frequencies of high-quality alleles, including 1, 7+9, 14+15 and 5+10. The genetic diversity of the four commercial wheat populations (alleles per locus (A) = 7.33, percent polymorphic loci (P) = 1.00, effective number of alleles per locus (Ae) = 2.347 and expected heterozygosity (He) = 0.563) was significantly higher than that of the landraces population, with the highest genetic diversity found in the Southwestern Winter Wheat Region population. The genetic diversity of HMW-GS is mainly present within the landraces and commercial wheat populations instead of between populations. The landraces were rich in rare subunits or alleles may provide germplasm resources for improving the quality of modern wheat.

Genetic Diversity of HMW-GS and the Correlation of Grain Quality Traits in Bread Wheat (Triticum aestivum L.) in Hubei Province, China

“…Moreover, 15 alleles were found at the Glu-1 locus in commercial cultivars from China by Gao et al [28]. Wang et al [21] reported 14 alleles in 131 commercial varieties of wheat in the middle and lower Yangtze River region. In the study of Farahani et al [29], 12 alleles were identified in Iranian commercial bread wheat cultivars.…”

“…The SDS-PAGE method reported by Wang et al [21] was used to identify the HMW-GS compositions. First, 40 mg of flour was added with 600 µL of SDS-PAGE buffer [62.5 mM Tris-HCl, pH 6.8, 2% (w/v) SDS, 10% (v/v) glycerol, 5% (v/v) 2-mercaptoethanol, 0.002% (w/v) bromophenol blue], and well shaken for 30 min.…”

The Impact of Trichoderma harzianum Together with Copper and Boron on Wheat Yield

“…For HMW-GS characterization, a single kernel was ground to fine powder for the identification of HMW-GS. About 10 mg of flour was taken in 400 μL of SDS-PAGE protein extraction buffer as previously described in ref . The SDS-PAGE gel analysis and electrophoresis were accomplished according to the methodology previously discussed in refs and .…”

“…60,61 The higher bread making quality is related to some HMW-GS subunits like 1Dx5+1Dy10, 1Bx14+1By14, and 1Ax1, whereas the dough strength is adversely affected by the presence of subunits like 1Dx2+11Dy12 and 1Bx20, and the bread making quality is positively affected by the subunits 1Dx17+1Dy18 and 1Ax2*. 54,59,62 Foliar application of micronutrients is an essential technique for increasing grain micronutrient contents and crop yields. Foliar application of Cu and B enhanced the growth and yield related attributes of wheat crop.…”

“…However, HMW-GS contributes only 10% of the total gluten protein and plays a key function in gluten elasticity . High molecular weight glutenin subunits are encoded by various genes located at Glu-A1 , Glu-B1 , and Glu-D1 loci present on the long arm of homologous chromosome A1, B1, and D1 . The dough and bread making quality of wheat are greatly related to the allelic variation and occurrence of HMW-GS. , The higher bread making quality is related to some HMW-GS subunits like 1Dx5+1Dy10, 1Bx14+1By14, and 1Ax1, whereas the dough strength is adversely affected by the presence of subunits like 1Dx2+11Dy12 and 1Bx20, and the bread making quality is positively affected by the subunits 1Dx17+1Dy18 and 1Ax2*. ,, …”