| Three unique hexaploid wheat, Yunnan wheat (Triticum aestivum ssp. yunnanense King), Tibetan wheat (Triticum aestivum ssp. tibetanum Shao) and Xinjiang wheat (T. petropavloski Udats et Migusch), were discovered in Yunnan province, Tibetan and Xinjiang autonomous regions of China, respectively. They have uniquely geographical distributions, highly genetic polymorphisms and distinctly morphological character such as glume color, rachis fragility, glume tenacity and long glume. Meanwhile, they have peculiar trails useful for wheat breeding, such as resistance to preharvest sprouting, cold tolerance or heat tolerance. All of their genome are AABBDD. Morphological and cytological studies showed that they are crossable with common wheat, and the progents produced could be highly fertile. The three unique wheats of western China are primary gene pool of the cultivated common wheat that interest genes from these species can be readily introduced into common wheat by genetic recombination, thus leading to an increase of genetic diversity of cultivated wheat.In order to find new genes for improvement of quality and increase of genetic diversity of the cultivated wheat, and to provide the further evidences for the evolution of these three unique wheat, genetic diversity including high molecular weight (HMW) glutenin subunits, gliadin, waxy, and simple sequence repeat (SSR), were analyzed using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), acid polyacrylamide gel electrophoresis (APAGE) and microsatellite molecular markers. The main results were as follows:1. Allelic variation and genetic diversity at HMW glutenin subunits loci in Yunnan, Tibetan and Xinjiang wheatTwo HMW glutenin patterns ("null, 7+8, 2+12" and "null, 7, 2+12"), three HMW glutenin patterns ("null, 7+8, 2+12"; "null, 6+8, 2+12" and"null, 7+8,2"), and one HMW glutenin pattern ("null, 7, 2+12") were found in the accessions of 34 Yunnan wheat, 24 Tibetan wheat, and 6 Xinjiang wheat, respectively. The Tibetan accession TB18 was found to have a rare subunit 2 encoded by Glu-D1. A total of 4 ( Glu-Alc, Glu-Bla, Glu-Blb and Glu-Dla), 5 (Glu-Alc, Glu-Bld, Glu-Blb, Glu-Dla and Glu-Dl) and 3 alleles (Glu-Alc, Glu-Bla and Glu-Dla) at Glu-1 locus were identified for the Yunnan, Tibetan and Xinjiang unique wheat accessions, respectively.The Nei's mean genetic variation indexes of Yunnan wheat, Tibetan wheat and Xinjiang wheat were 0.1574, 0.1366 and 0, respectively, showing the higher genetic diversity at HMW glutenin subunits loci of Yunnan and Tibetan wheat as compared to that of Xinjiang wheat. The highest Nei's genetic variation index was in B genome with the mean value of 0.2674, while the indexes of genome A and D were 0 and 0.0270, respectively. In conclusion, Glu-Bl showed the highest, Glu-Dl the intermediate and Glu-Al always the lowest genetic diversity.2. Allelic variation and genetic diversity at Gli-1 and Gli-2 loci in Yunnan, Tibetan and Xinjiang wheatA total of 26, 33, and 3 alleles at Gli-1 loci and 15,16, 3 alleles at Gli-2 loci were found in 34 Yunnan, 24 Tibetan and 6 Xinjiang wheat accessions, respectively. Some new alleles were identified in Yunnan and Tibetan wheat accessions at Gli-Bl, Gli-Dl and Gli-A2 loci.The highest Nei's genetic variation index was in B genome among the three genomes, showing that B genome has the highest genetic variation of Gli-1 and Gli-2 loci. The Nei's mean genetic variation indexes of Yunnan wheat, Tibetan wheat and Xinjiang wheat were 0.6824, 0.7471 and 0, respectively, thus Yunnan wheat andTibetan wheat have higher genetic diversity than Xinjiang wheat.3. Identification of waxy protein in Yunnan wheat, Tibetan wheat and Xinjiang wheatA collection of 64 Yunnan, Tibetan and Xinjiang wheat was analyzed for waxy protein in the grain by SDS-PAGE. The electrophoretic patterns showed that all accessions had the Wx-Ala, Wx-Dla and Wx-Bla alleles. No allelic variation was found at the Wx-Ala, Wx-Dla and Wx-Bla loci.4. Assessing genetic diversity of Yunnan, Tibetan and Xinjiang wheat using SSR markersA tot...
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