利用SSR标记对不同类型抗虫棉品种的遗传多样性分析

以97014，BR—S-10和sGK321等14份不同类型的抗虫棉花品种（系沩试验材料，利用SSR分子标记技术，对这些棉花品种（系）的遗传多样性进行了研究．结果表明，从126对SSR引物筛选出的22对引物均能在14份抗虫棉品种（系）中产生明显的扩增差异带，共检测出97个等位基因位点，其中多态性位点69个，多态性比率达71．1％．引物等位位点数在2～7个，平均每对引物为4．4个．利用Jaccard遗传相似系数计算了14份抗虫棉品种（系）的SSR数据的距离矩阵，按UPGMA方法进行聚类，发现14个品种（系）间的遗传距离在0．035～1．056．聚类分析表明，14份棉花品种（系）可分为2大类4亚类，其中，第1大类是以转基因的抗虫棉为主，第Ⅱ大类包括3个品种（系），分别是中棉所的ISA4ne，BR—S-10和湖南农业大学的97014，这3个品种都为无蜜腺的形态抗虫棉品种，故较早的聚为一类．本研究表明，用SSR分子标记技术分析棉花不同品种间的遗传多样性是町靠的，揭示了抗虫棉花品种种质资源的多样性，大多数品种的遗传基础比较狭窄．

Genetic Diversity Analysis and Identification of Insect-Resistant Cottons Based upon SSR Markers

Genetic diversity analysis and identification of 14 different germplasm varieties(lines) from insect-resistant cotton by the simple sequence repeats(SSR) amplified polymorphic DNAs techniques were reported.A total 126 pairs of SSR primers were used to the 14 different germplasm varieties(lines) using SSR techniques and finally 22 pairs of primers could produce steady polymorphisms.A total of 97 DNA fragments were scored among all materials,averaging 4.5 for each pair of primer,of which,69(71.1%) bands were polymorphic.Cluster analysis by the unweighted pair group method of arithmetic means(UPGMA) showed that 14 varieties(lines) could be divided into two groups with genetic distance from 0.035 to 1.056.Cluster analysis revealed that 14 lines could be divided into two groups and the first group that included 11 varieties mainly were transgenic pest-resistant cotton,and the second group that included 3 varieties,were the nectariless pest-resistant cotton.This experiment demonstrated that SSR analysis could reliably determine genetic relationships within a diverse array of cotton varieties.The analysis revealed that it was corresponding to the geographical distribution and most of the lines had a narrow genetic base.