【摘要】 采用ISSR分子标记技术对中国不同产地的35份山药种质资源进行遗传多样性分析,并用最小遗传距离逐步抽样法构建核心种质库。结果表明:(1)筛选出12个有效引物共扩增出142个位点,多态性比率为97.18%,平均Shannon’s信息指数(I)为0.4230,平均Nei’s基因多样性指数(h)为0.269 4,平均有效等位基因数(Ne)为1.427 1,平均等位基因数(Na)为1.971 8,说明35份山药种质遗传多样性很丰富。(2)聚类分析表明,种质间的遗传相似系数介于0.54~0.97之间,其中来源地不同的个别种质间的遗传相似系数也很高。(3)经6次逐步抽样,随着抽取种质数目的减少,种质库遗传多样性参数变化不明显,而多态性比率在其中5次逐步抽样中呈现下降趋势;但抽样4在抽样数是抽样前的31%时,多态位点率仍可达到抽样前的97.8%,说明抽样4所构建的山药核心种质库最具代表性。更多还原

【Abstract】 The genetic diversity of 35 germplasm resources of yam from different places and areas were analyzed by ISSR molecular marker and the primary core collection was constructed by Least Distance Stepwise Sampling.The results showed that:(1)12primers selected from 32 random ISSR primers which amplified 142 loci including 97.18% polymorphic loci.The average of Shannon information index(I),Nei’s genetic diversity(h),effective number of alleles(Ne)and number of alleles(Na)by POPGENE 32 analysis was 0.423 0,0.269 4,1.427 1and 1.971 8respectively which indicated there was highly genetic diversity in these 35 yam resources.(2)The clustering result of analysis by NTsys2.10 esoftware showed that the genetic similarity coefficient ranged 0.54-0.97.Some materials distributed in different origins and far geographic distance showed high genetic similarity coefficient in 35 accessions.(3)The percentage of polymorphic loci was reduced although the change of Shannon’s information index and Nei’s genetic diversity was not clear with the samples reduced in six samplings.The bank of core collection from No.4sampling wasmost representative in six samplings whose sampling number was 31% of the initial sampling and the percentage of polymorphic loci was 97.8% before sampling.更多还原