利用SRAP和EST-SSR分析香椿资源的遗传多样性

利用SRAP和EST-SSR标记技术对中国9省10个香椿居群的遗传多样性和亲缘关系进行了分析，试图为香椿种质资源的保护和开发利用奠定基础。结果表明，33对SRAP标记共扩增出167个多态性位点，平均每对引物产生5.06个多态性位点；45对EST-SSR引物共检测到221个多态性位点，平均每对引物检测到4.9个多态位点；所选香椿居群的等位基因数和期望杂合度（EST-SSR，Na = 2.3506，He = 0.4632）及Shannon’s信息指数（SRAP，I = 0.6140；EST-SSR，I = 0.6752）较高，表明中国香椿资源具有较高的遗传多样性；居群间的遗传分化系数（SRAP，Gst = 0.3124；EST-SSR，Fst = 0.2462）表明所研究的香椿资源分化程度较高；聚类结果显示，10个香椿居群可分成3类，其中衡水、泰安和太和居群为一类，成都、昆明、武汉和汝阳居群为一类，德州和泉州居群聚为一类，南京居群的结果因两类引物略有不同；香椿居群间的遗传距离与实际的地理距离相关性不显著。

Genetic Diversity Analysis of Toona sinensis Germplasms Based on SRAP and EST-SSR Markers

Expressed sequence tags（EST）- simple sequence repeats（SSR）and sequence related amplified polymorphism（SRAP）markers were applied to assess the genetic diversity and genetic relationship of 10 Toona sinensis populations collected from nine provinces in China. A total of 167 polymorphic loci were detected by 33 SRAP primers with 5.06 polymorphic loci per primer，and 221 polymorphic loci were observed by 45 EST-SSR primers with 4.9 alleles per primer. The results of observed number of alleles（EST-SSR，Na = 2.3506），expected heterozygosity（EST-SSR，He = 0.4632）and the Shannon’s information index（SRAP，I = 0.6140；EST-SSR，I = 0.6752）demonstrated that relatively higher level of genetic diversity possessed in these populations of T. sinensis. The genetic differentiation coefficients data（SRAP，Gst = 0.3124；EST-SSR，Fst = 0.2462）also revealed relatively higher level of genetic polymorphisms among these T. sinensis resources. Cluster analysis divided 10 populations into 3 groups，one group consisted of Hengshui，Tai’an and Taihe populations，another group consisted of Chengdu，Kunming，Wuhan and Ruyang populations，Dezhou and Quanzhou populations were belonging to the third group. The results of Nanjing population were different in two kind of markers. Genetic relationship among these T. sinensis populations have no significant correlation with their geographical distribution.