Abstract:

High molecular wight glutenin subunits(HMW-GS) are important element of wheat storage proteins, they play a key role in determining bread making quality. Also they can be used to study the origin, evolution and genetic differentiation of hexaploid wheat. In this study, we explored the composition of HMW-GS of three Chinese endemic wheat landraces (T. petropavlavskyi, T. tibetanum, T. yunnanense). Combining the result with some previous research, we analysed the polymorphism of HMW-GS in these three landraces, common wheat, spelt and club wheat. It was found that the composition of HMW-GS in spelt has its unique character: (1) the subunit 1 on Glu-A1 is predominant in spelt; (2) subunits 13+16 on Glu-B1 is predominant in spelt but unfrequent in other hexaploid wheat. Some special types of HMW-GS were found in the accessions of T. petropavlavskyi, which were rarely found or never be reported in other hexaploid wheat (including Aegilops tauschii). It is concluded that the common wheat is the possible provider of the cytoplasm of T. petropavlavskyi and the origin of the nucleolus genome of T. petropavlavskyi is very complicated, and maybe from Polish wheat, common wheat and Aegilops tauschii originated in Xinjiang Province, and its evolution routine needs to be more closely studied in the future.

Key words: Chinese endemic wheat landraces, HMW-GS, Polymorphism