利用149对具有多态性的In Del引物对473份黄瓜初选核心种质自交系进行遗传多样性分析。采用3种方法 12种取样比例对该初级遗传多样性固定群体进行抽样获得候选多样性固定核心样本集(GDFCC),使用等位基因数(Na)、有效等位基因数(Ne)、Shannon's信息指数(I)、基因多样性指数(gene diversity)、多态性信息含量(PIC)、总等位位点数(total number of loci)、等位位点保留百分率(retention rate of loci)评价候选多样性固定核心样本集的多样性和代表性,结果表明,采用逐级聚类+稀有基因优先取样法并按照15%取样比例构建出的多样性固定核心样本集的效果较好。比较发现,该核心样本集的Ne、I、基因多样性指数和PIC值均接近或高于初级遗传多样性固定群体,且对原始群体的等位位点的保留百分率为99.68%。入选多样性固定核心样本集的材料来自15个国家和国内18个省市。该研究为今后黄瓜优异基因资源的挖掘利用提供了代表性强、覆盖度广、遗传稳定的研究群体,将有利于黄瓜种质资源的高效研究利用。
In this study,149 pairs of In Del primers were used to analyze the genetic diversity of 473 inbred lines of a primary core collection in cucumber. Three methods with twelve sampling proportions were applied to sample the candidate genetic diversity fixed core collections( GDFCC),number of alleles( Na),number of effective alleles( Ne),Shannon's information index( I),gene diversity,polymorphism information content( PIC),total number of loci and retention rate of loci were used to test diversity and representativeness of the candidate GDFCCs. The results indicated that the method of stepwise clustering plus rare genes preferred sampling with 15% sampling proportion was more efficient for the GDFCC construction. By comparison,Ne,I,gene diversity and PIC of the GDFCC were higher than those of the primary core collection,and the retention rate of loci in the GDFCC reached 99. 68%.The materials of the GDFCC comes widely from eighteen provinces in China and fifteen foreign countries with a rich diversity and representation. This study provides with a valuable population with genetic stability and extensive representativeness for promoting efficient research and utilization of cucumber germplasm resources.