利用SSR分子标记进行海岛棉遗传多样性研究

利用SSR分子标记,对20世纪50年代我国引入海岛棉以来培育的45个国内品种(系)及8个国外品种的遗传多样性进行研究.通过256对SSR引物的筛选,选择24对扩增效果好的引物对53个海岛棉种质资源进行遗传多样性的检测分析,共检测出106个等位位点,每对引物等位位点数在2～8之间,平均为4.4.其中多态性等位基因变异97个,占91.5%.位点多态性信息含量平均为0.688,最高为0.848,最低为0.245.利用NTSYSpc2.1软件,分别计算农艺经济性状的欧氏距离(Euclid)和分子标记数据的Jaccard系数矩阵,采用UPGMA法对所选材料进行聚类分析.结果表明,两个树状聚类图基本吻合,53个品种被分为两大类,与系谱来源一致.实验证明SSR分子标记在鉴别品种和品种遗传多样性研究方面具有重要作用.

Genetic Diversity of Sea Island Cotton Using SSR Markers

Genetic diversity of 45 Chinese Sea Island Cottons and 8 foreign Sea Island Cottons were studied based on SSR (Simple Sequence Repeats ) markers.Twenty-four SSR primers were selected from 256 primers to evaluate the genetic diversity of 53 Gossypium barbadense L. germplasms. Totally 106 alleles were observed among which, 97 (91.5%) were polymorphic. The number of DNA bands per primer ranged from 2 to 8 and with the average of 4.4. The average polymorphism information (PIC) was 0.688,with the range from 0.245 to 0.848. Cluster analysis by the unweighted pair group method of arithmetic means (UPGMA) showed that 53 varieties were clustered into 2 main groups based on Jaccard similarity from the SSRs and Euclid distance from 17 agronomic traits data. Classification of all genotypes gave similar results with their line sources. Genetic relationships and the genetic similarity obtained from the analysis is used for the evaluation of varieties and genetic diversity.