迪庆州核桃种质资源的遗传多样性与遗传结构

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 Resources in Diqing

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.