迪庆州核桃种质资源的遗传多样性与遗传结构

Genetic Diversity and Genetic Structure of Walnut Germplasm Resources in Diqing

利用SSR分子标记技术对云南省迪庆藏族自治州3个群体共161份深纹核桃种质资源进行遗传多样性分析,揭示资源的遗传多样性水平及遗传结构特征,为其保护和利用提供依据。结果表明:18对SSR引物对161份DNA样本进行扩增,共检测到171个等位基因,平均每对引物9.5个。3个群体的观察杂合度(H_(o))和期望杂合度(H_(e))的变化范围分别为0.390~0.580和0.580~0.619,平均值分别为0.467和0.598;Shannon信息指数(I)介于1.153~1.313之间,平均为1.231,数据表明迪庆州核桃种质资源的遗传多样性属于中等水平。群体间的遗传分化系数(F_(ST))介于0.0052~0.2253之间,平均为0.0652,表明遗传变异主要来源于群体内的个体,仅有6.52%来源于群体间,各位点的基因流(N_(m))平均为4.2663(N_(m)>1),群体间的基因交流阻止了群体间的分化。STRUCTURE分析将161份核桃资源分成3个类群,而基于Nei’s遗传距离的UPGMA聚类将3个群体划分成2组,维西和香格里拉聚为一组,德钦单独为一组。

Genetic diversity and genetic structure of walnut germplasm in Diqing Prefecture of Yunnan was analyzed using SSR molecular markers.Eighteen SSR primers were employed to amplify 161 samples from 3 populations of Juglans sigillata in Diqing and 171 alleles were detected with a mean value of 9.5 per locus.The range of obseved heterozygosity(H_(o))and expected heterozygosity(H_(e))were 0.390-0.580 and 0.580-0.619 respectively with average of 0.467 and 0.598,and the range Shannon information index(I)was between 1.153-1.313 with an average of 1.231.The results indicated that the genetic diversity of walnut germplasm in Diqing was moderate.The coefficient of genetic differentiation(F_(ST))was 0.0052-0.2253 with an average of 0.0652,which meant only 6.52%of variation existing among populations.The gene flow(N_(m))was 4.2663(N_(m)>1)showing that gene flow prevented the differentiation among populations.161 individuals were divided into 3 groups through STRUCTURE analysis and 3 populations were clustered into 2 branches through UPGMA clustering.Weixi and Xianggelila were clustered in one branch and Deqin as another branch.