Distribution of low-molecular-weight glutenin subunit Glu-B3 alleles in mini core collections of Chinese wheat germplasms

摘要

Low-molecular-weight glutenin subunit (LMW-GS) Glu-B3 plays an important role in the processing quality of the wheat used to make bread and noodles. A total of 214 accessions of common wheat (Triticum aestivum L.) comprising both landraces and improved cultivars collected from all the three growing zones in China were tested for ten alleles using 10 allele-specific PCR markers at the Glu-B3 locus. The frequency of the ‘i’ allele (20.6%) was greater than those of the other alleles. The ‘i’ allele was found in 18.7% of landraces and 23.8% of improved cultivars. The alleles, from most to least common, were ‘i’>‘a’>‘d’>‘g’>‘f’>‘b’>‘e’>‘c’>‘j’>‘h.’ In the spring wheat zone, the Glu-B3 alleles were mainly ‘g’ and ‘i,’ but in the winter wheat zone, they were mainly ‘a’ and ‘i.’ The ‘h’ allele was only found in the spring wheat zone, but the ‘a’ and ‘c’ alleles were found in small proportions in the spring wheat and spring-winter wheat zones. The frequency of the ‘i’ allele was more than twice that of the b allele (9.3%). Because the ‘b’ allele has a more pronounced effect on gluten strength, varieties with the ‘b’ allele can be considered suitable for the breeding of new, high- quality cultivars.