山茱萸种质资源的ISSR遗传多样性分析与初级核心种质库的构建

Genetic Diversity and Construction of Primary Core Germplasm in Cornus officinalis by ISSR Marker

采用ISSR标记技术对不同来源地的48份山茱萸种质资源的遗传多样性进行了分析,并依据最小遗传距离逐步抽样法构建了该初级核心种质资源库。结果显示：筛选出的13个多态性引物共扩增出190个位点,多态性位点比率达93.16%,平均Shannon信息指数（I）为0.402 5,平均Nei’s基因多样性指数（H）为0.259 4,平均有效等位基因数（NE）为1.425 0。聚类分析表明,种质间的遗传相似系数介于0.65-0.90之间,除个别种质外,48个种质聚类结果与地区来源有较高的一致性。随着抽取种质数目的减少,多态性比率明显降低,但种质库遗传多样性参数变化较小;抽样3构建的初级核心种质库最具代表性,抽样数是抽样前的30%左右,多态位点比率是抽样前的96.0%。

The genetic diversity of 48 germplasm resources of Cornus officinalis in Zhejiang,Henan and Shaanxi Province were analyzed by ISSR technique,and the primary core germplasm were constructed with progressive sampling method of smallest genetic distance.13 primers,which showed good repetitive,special bands and distinct polymorphism,were selected from 51 random ISSR primers.Then the total 190 loci were amplified by these selected 13 primers,including 93.16% polymorphic loci.The results indicated that the average of Shannon information index（I）,Nei＇s genetic diversity（H） and effective number of alleles（NE） by POPGENE32 analysis were 0.402 5,0.259 4 and 1.425 0,respectively.The result of analysis by NTSYS-PC software showed there was upper coherence between the clustering result and source core germplasm collection.The result showed the index change of germplasm genetic diversity was less than that before sampling.Although the Shannon＇s information index and Nei＇s genetic diversity were increased a little,the percentage of polymorphic loci was obviously reduced.The bank of core germplasm from No.3 sampling was most representative,whose sampling number was about 30% of the initial sampling,and the percentage of polymorphic loci was 96.0% before sampling.