Characterization of high- and low-molecular-weight glutenin subunits from Chinese Xinjiang wheat landraces and historical varieties

Abstract

Landraces and historical varieties are necessary germplasms for genetic improvement of modern cereals. Allelic variations at the Glu-1 and Glu-3 loci in 300 common wheat landraces and 43 historical varieties from Xinjiang, China, were evaluated by Sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and allele-specific molecular markers. Among the materials investigated, three, nine, and seven alleles were identified from the Glu-A1, Glu-B1, and Glu-D1 loci, respectively, and a total of 26 high-molecular-weight glutenin subunit (HMW-GS) combinations were found, of which 18 combinations were identified in landraces and historical varieties. Allelic frequency of HMW-GS combinations null, 7 ? 8, 2 ? 12 was found to be the highest in both the landraces (63.3%) and historical varieties (39.5%). Besides, some distinctive HMW-GS alleles, such as the novel Glu-B1 allele 6.1* ? 8.1* and Glu-D1 alleles 2.6 ? 12, 2.1 ? 10.1, and 5** ? 10 were observed in Xinjiang wheat landraces. Among the Glu-A3 and Glu-B3 loci of landraces and historical varieties, a total of eight and nine alleles were found, respectively. At each locus, two novel alleles were identified. A total of 33 low-molecularweight glutenin subunit (LMW-GS) combinations of Glu-A3 and Glu-B3 were identified, with 31 and 14 combinations occurring in landraces and historical varieties, respectively, but only 10 combinations shared by both of them. As Glu-D1, Glu-A3, and Glu-B3 have highest contribution to the end-use quality and processing properties as compared to Glu-A1, Glu-B1, and Glu-D3 locus, the novel or distinctive HMW-GS and LMW-GS alleles in these loci could potentially be utilized for the improvement in the quality of modern wheat.

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

“…In the current study, the frequency of the Glu-D1a (2+12) allele was far higher in the landraces than commercial cultivars. Previous reports also showed that the allele Glu-D1a (2+12) was the most frequent in Chinese and Japanese wheat landraces (Dai et al 2020, Nakamura 2000, Zhang et al 2002, Zheng et al 2011. For commercial cultivars, allele Glu-D1a (2+12) also appeared more than allele Glu-D1d (5+10) although the latter allele also appeared as a common allele, which is in agreement with previous results (Gao et al 2018, Liu et al 2005.…”

Characterisation of synthetic hexaploid wheat (BBAuAuAmAm) and its potential use in wheat breeding

“…López-Fernández et al (2021) the Glu-B1 locus in the 189 Spanish landraces analysed, among which the allele i coding for HMW-GS 17+18 was found at a low frequency of 1.59%. The same tendency for this allele was described by Dai et al (2020) who found it in only spring forms of Chinese Xinjiang wheat landraces and historical cultivars.…”

Exploring the End-Use Quality Potential of a Collection of Spanish Bread Wheat Landraces

“…Some rare combinations (i.e., 5+12, 2+12*, 12, and 2+10´) appeared at a low frequency. These combinations have been previously described in other germplasm collections [ 62 , 63 , 64 ], but this is the first time that they have been reported in Iberian landraces, probably due to the large number of and high diversity in the accessions analyzed here.…”

“…This may be due to the difficult assignment of this glutenin subunit using only standard SDS-PAGE electrophoresis but could also indicate that it is characteristic of Iberian landraces [42]. Regarding the Glu-B1 locus, it is worth noting that Spanish landraces present a high frequency of the subunit pairs 20x+20y and 13+16, whereas these combinations are absent in landraces from other regions of the world [60][61][62][63][64], indicating the specific conservation of these alleles in the Iberian Peninsula. The 13+16 pair has also been described at a high frequency (88%) in Triticum aestivum ssp.…”