High frequency of abnormal high molecular weight glutenin alleles in Chinese wheat landraces of the Yangtze-River region

A total of 485 common landraces of bread wheat were collected from the Yangtze-River region of China. Their high molecular weight glutenin subunit (HMW-GS) composition was analyzed by Matrix-assisted laser desorption/ionization time-of-flight Mass Spectrometry (MALDI-TOF-MS). Among all landraces tested, 453 were homogeneous for HMW-GS, 32 were heterogeneous, and 37 contained abnormal subunits. A total of 22 alleles were detected, including 3 at Glu-A1, 13 at Glu-B1 and 6 at Glu-D1, respectively. Higher variations occurred at the Glu-B1 locus compared with Glu-A1 and Glu-D1. Glu-A1c (74.0%), Glu-B1b (40.4%), Glu-D1a (84.9%) appeared to be the most frequent alleles at Glu-A1, Glu-B1 and Glu-D1, respectively. Two alleles ("null" and 1) at the Glu-A1 locus, three allele compositions (7 + 8, 7OE + 8, 7 + 9) at the Glu-B1 locus, and two (2 + 12 and 5 + 10) at the Glu-D1 locus appeared to be the common types in the 485 landraces. Sixteen new alleles represented by abnormal subunits were identified at the Glu-B1 and the Glu-D1 locus.

► MALDI-TOF was used to analyse 485 wheat landraces from the Yangtze-river region of China.
► High frequency of abnormal HMWGS alleles is identified.
► A total of 37 lines contained abnormal subunits with 16 new alleles.