| Because of the improvement of technique in wheat breeding and the introduction of desirable genetic germplasm to cultivated wheat, some good cultivars were successfully bred and more and more new cultivars were released in recent years. The genetic diversity of cultivated wheat has been gradually reduced by the frequently using similar or same parental genotypes in wheat improvement. Thus, it is important to evaluate the genetic diversity of present cultivars in order to sound genetic basis and change breeding strategy. The objectives of this study were to detect the genetic diversity of 47 wheat cultivars (lines) which were released from 1960s in Sichuan province by using APAGE, SDS-PAGE and SSR markers. The results were described as followings:1. 47 gliadin bands were separated by APAGE among 47 tested cultivars (lines) and 39 out of them showed polymorphism (82.98%). Most of cultivars (lines), even sister lines from the same cross, could be identified by gliadin patterns. The results indicate that there are abundant allelic variations at gliadin loci among tested cultivars (lines).2. According to whether Gli-B11 locus existed or not, 11 1RS/1BL translocation lines (23.4%) were detected among tested cultivars (lines). It is suggested that 1RS/1BL translocation lines proportionally exist in Sichuan cultivated wheat and play an important role in wheat improvement. However, the breeders also pay attention to the negative effect of 1RS/1BL for the end-use of wheat.3. Using SDS-PAGE analysis, 7 high-weigh-molecular (HWM) glutenin subunits were found among tested cultivars (lines). The alleles were Glu-Ala (42.6%), Glu-Alc (57.4%), Glu-Blb (55.3%), Glu-Blc (31.9%), Glu-Ble (10.9%), Glu-Dla (72.3%), Glu-IDd (27.7%). 4 principal HWM glutenin subunits combinations among 10 were (null, 7+9, 2+12)(21.74%), (null, 7+8, 2+12)(19.57%), (1, 7+8, 2+12)(17.39%), (null, 7+8, 5+10)(13.04%). The frequency of subunit (5+10) which contribute to good quality of end-use was low and other good subunits, such as subunits 2* and 17+18, were not found. The results show that the HWM glutenin subunits compositions and the good subunits are relatively lower among tested cultivars (lines) in Sichuan province.4. 7 out of 21 pairs of SSR primers located on the first and sixth homoeologous chromosomes were polymorphism among tested cultivars (lines). While the other SSR primers were not polymorphism. Primer (Xgwml32) amplified polymorphism patterns only in chuanyu cultivars. It could draw a conclusion that the genetic polymorphism of the DNA sequence might be relatively lower on the first and sixth homoeologous chromosomes among tested cultivars (lines).5. The comparison of the Nei's genetic similarity (GS) indexes based on storage protein and SSR markers revealed that the variation of DNA sequences was lower than that of storage protein. In addition, although the correlation index was low, mantel testrevealed that the goodness of fit between protein and SSR markers based on their GS matrix was significant. The UPGMA cluster graphs between protein and SSR markers also proved their correlation. This reveals the validities of using two markers to detect genetic diversity.6. 60 SSR markers located on 42 chromosomes were randomly selected to detect the genetic diversity among 47 cultivars (lines). 35 out of 60 SSR primers (58.33%) were polymorphism and a total of 108 alleles had been obtained. In all primers, 11 pairs of primers could amplify polymorphism patterns in all tested cultivars. The primers Xgwm328-2A, Xgwml32-6B and Xgwm469-6D, Xgwml35-lA and Xgwml46-7B, amplified polymorphism patterns in chuanyu cultivars, chuanmai cultivars, mianyang cultivars (lines), respectively. Furthermore, 47 cultivars (lines) could be distinguished only by 6 SSR markers. That is to say, the cultivars (lines) from three breeding units are different on DNA level to some degree.7. The comparison of A, B, D chromosomes based on polymorphism index indicated that the polymorphism in genome B was the highest and in genome...
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