| To assess the genetic diversity of Tibetan wheat landraces from the agronomic traits, storage proteins, DNA aspects, 1622 Tibet wheat landraces had been analysied by SDS-PAGE, A-PAGE, SSR with field trail. The deployment and utilization of desirable genes from Tibet wheat landraces are important in development of Tibet modern wheat cultivars.Experimental results were as follows:(1)Analyzed and compared the genetic diversity in main agronomic traits of 1622 landraces , which were from six sub ecotype in Tibet .The result showed that there were abundant genetic diversities.The genetic diversity index of overall material was 1.4015.Among the different sub ecotypies, the genetic diversity index (1.4288) in IV was highest, displaying for high abundance and good uniformity of genetic diversity. Sub ecotypies with the higher genetic diversity index were I and III, were 1.3956 and 1.3823 respectively.The lowest was V, which was only 0.4757.(2)Analyzed and compared the genetic diversity in Glu-1 of 1057 landraces, The genetic variation index was 0.4287 and the genetic diversity index was 0.77. Among the different sub ecotypies, the genetic variation index from the highest to lowest were South Tibet Winter & Spring Wheat Area (0.2574), East Tibet Winter & Spring Wheat Area, the Frontier of South-East & South Tibet Winter Wheat Area, South-West Tibet Winter & Spring Wheat Area and West Tibet Spring Wheat Area (0.1250).Compared the genetic diversity index the highest one was East Tibet Winter & Spring Wheat Area, which was 0.4883. The lowest one was West Tibet Spring Wheat Area, which was 0.1874. Analyzed and compared the genetic variation index and the genetic diversity index of the 1057 landraces, all the material had showen that the highest ones were on Glu-B1 and the lowest ones were on Glu-D1.(3)210 wheat varieties from Tibet wheat had been studied to investigate the relationships between protein contents, sedimentation value and high molecular weight gluten subunits(HMW-GS)。There were three kinds of HMW-GS on Glu-A1,the contributions of variation in Glu-A1 to the quality traits were determined as 2*>1>null。There were eight kinds of HMW-GS on Glu-B1,The contributions of variation in Glu-B1 to the protein contents were determined as 7>14+15>17+18>6>7+9>22>7+8>6+8,There were three kinds of HMW-GS on Glu-D1,Their contributions to the protein contents were determined as 5+10>12>2+12. Their contributions to the sedimentation value were 2*>1>N, 17+18>7>14+15 >7+9>7+8>6>6+8>22 and 5+10>2+12>12 separately。Combining the sedimentation value and the protein contents as the evaluation index, the best subunit combinations was 2*/14+15/17+18/5+10. The protein contents corresponding to the subunit combinations appeared significant positive correlation with sedimentation value(r=0.5571*).(4)The standard gliadin fingerprints and database of 571 Tibet wheat landraces had been made by using A-PAGE method. There were 104 different gliadin bands. Among themω,γ,βandα-gliadin had 34,20,22 and 28 bands respectively, andω,γ,βandα-genetic diversity index were 0.1920,0.2432,0.2470 and 0.2100 respectively. Compared the different sub ecotype areas, the genetic diversity index from the highest to lowest were as follow: South Tibet Winter & Spring Wheat Area, the Frontier of South-East & South Tibet Winter Wheat Area, East Tibet Winter & Spring Wheat Area South-West Tibet Winter & Spring Wheat Area and West Tibet Spring Wheat Area. The result from clusting analysis indicated that when GS was at the level of 0.11, 571 accessions there were no difference, while GS was at the level of 0.24, 571 accessions they could be divided into seven big groups.(5)The 21 selected microsatellite markers revealed a total of 138 alleles among 36 accessions,the number of alleles per locus ranged from 1 to 16 ,with an average of 6.57 alleles. The genetic diversity index was 1.0985. At the genome level, D genome showed the highest, A genome the intermediate and B genome always the lowest allelic polymorphism. The result from clusting analysis indicated that when GS was at the level of 0.74,36 accessions had no difference, while GS was at the level of 0.777, 36 accessions could be divided into four big kinds.(6)The comparison of the genetic similarity (GS) indexes based on storage protein and SSR markers revealed that the variation of storage protein was lower than that of DNA sequences. The mantel test revealed that the goodness of fit between protein and SSR markers based on their GS matrix was significant. The UPGMA cluster graphs with protein and SSR markers proved their correlation. This reveals the validities with two markers to detect genetic diversity.( 7 ) Accounted the complicated genetic diversity index from the agronomic traits ,storage protein, DNA aspects, and Compared the different sub ecotype areas, the genetic diversity index from the highest to lowest was as follow: South Tibet Winter & Spring Wheat Area, East Tibet Winter & Spring Wheat Area, the Frontier of South-East & South Tibet Winter Wheat Area, South-West Tibet Winter & Spring Wheat Area and West Tibet Spring Wheat Area.
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