Date Published: July 6, 2017
Publisher: Public Library of Science
Author(s): Zhenying Dong, Yushuang Yang, Kunpu Zhang, Yiwen Li, Junjun Wang, Zhaojun Wang, Xin Liu, Huanju Qin, Daowen Wang, Guihua Bai.
In common wheat (Triticum aestivum L.), allelic variations of Glu-A1 locus have important influences on grain end-use quality. Among the three Glu-A1 alleles, Glu-A1a and -A1b encode the high-molecular-weight glutenin subunits (HMW-GSs) 1Ax1 and 1Ax2*, respectively, whereas Glu-A1c does not specify any subunit. Here, we detected a total of 11 Glu-A1 locus haplotypes (H1 to H11) in three wheat species, by developing and using a new set of DNA markers (Xrj5, Xid3, Xrj6, Xid4 and Xrj7). The main haplotypes found in the diploid wheat T. urartu were H1, H4, H5 and H6, with H1 and H4 expressing both 1Ax and 1Ay subunits. The major haplotypes revealed for tetraploid wheat (T. turgidum) were H1, H8 and H9, with the lines expressing both 1Ax and 1Ay belonging to H1, H4 or H7. Four major haplotypes (H1, H9, H10 and H11) were discovered in common wheat, with Glu-A1a associated with H1 and H8, Glu-A1b with H10 or H11, and Glu-A1c with H9. The Glu-A1 locus haplotypes and the new set of DNA markers have potential to be used for more effectively studying and utilizing the molecular variations of Glu-A1 to improve the end-use quality of common wheat are discussed.
Common wheat (Triticum aestivum, 2n = 42, AABBDD) is one of the most important staple food crops in the world, providing 20% of dietary energy and protein sources for over 60% of the world population [1, 2]. T. aestivum was originated about 10,000 years ago due to natural hybridization between tetraploid wheat (T. turgidum, 2n = 28, AABB) and the D genome donor Aegilops tauschii (2n = 14, DD) [3, 4]. T. turgidum was derived from the hybridization between T. urartu (2n = 14, AA) and an unknown species of the Sitopsis section about 0.5 million years ago . Both T. urartu and T. turgidum contain the A genome, which is closely related to the A genome present in bread wheat.