应用微卫星标记分析柱花草的遗传多样性

采用18个微卫星(SSR)DNA标记对42个柱花草品系进行了遗传多样性分析，共扩增出84条带，其中多态性带71条，平均多态性水平为84．5％。运用POPGEN32软件计算了各品系的等位基因频率、多态性信息含量、遗传杂合度、等位基因数及有效等位基因数，结果表明，抗病柱花草品系的遗传变异高于感病柱花草品系的遗传变异程度。用NTSYS-pc软件计算品系间的遗传相似系数，其变化范围为0．26～0．94。按非加权成对平均数法(UPGMA)进行聚类分析，获得了聚类树系图，以所有品系的平均遗传相似系数0．60为阈值，42个品系分为6类。这些结果表明，SSR技术是分析柱花草遗传多样性的有效方法。

SSR Analysis of Genetic Diversity among Stylosanthes guianensis Accessions

Simple Sequence Repeats (SSR) analysis was used to determine the genetic diversity among 42 accessions of Stylosanthes guianensis with 18 microsatellite primer sets, and a total of 84 bands with 71 polymorphisms were scored, showing a 84.5% level of polymorphism on average. The allele frequencies, polymorphism information content, genetic heterozygosity, number of allele, number of effective allele of 42 accessions were estimated with POPGEN32 (Version 1.31) software, and the result showed that the genetic variability of resistant accessions was higher than that of the susceptible. Genetic similarity from 26.0% to 94.0% among the accessions was calculated with NTSYS-pc software. The dendrogram was constructed with UPGMA (unweighted pair group method of averages) based on the SSR markers, and 6 clusters were defined at 60% genetic similarity. Also, these results demonstrate that SSR analysis is an efficient method for evaluating the genetic diversity among S. guianensis accessions.