用ISSR标记技术分析山药品种遗传多样性

利用ISSR标记技术对28个山药品种的遗传多样性进行分析。结果表明，从44条ISSR引物中可筛选出7条能够扩增出清晰、稳定条带的引物；这7条ISSR引物对28个山药品种扩增条带间存在较大差异，多态性条带比率为83．01％，Shannon多样性指数为0．3191；构建的分子树状图将28个山药品种划分为4组：第一组含有日本白、花山药和日本园3个品种；第二组为小叶山药；第三组为嵩野1号；其余23个品种归入第四组。而且主成分分析结果支持上述的聚类分析结果。这为利用ISSR标记技术鉴定山药品种，为有效地利用山药种质资源提供了依据。

Genetic diversity of yam (Dioscorea opposita Thunb) detected by ISSR markers]

Genetic diversity of 28 cultivars of yam (Dioscorea opposita Thunb) was assessed by means of Inter-simple sequence repeat (ISSR) markers. The results showed that seven proper primers, with rich polymorphism, could be selected from a total of forty four ISSR ones; distinct differences appeared among 28 cultivars amplified bands, and the rate of polymorphic bands was 83.01%; Shannon's Information index was 0.3191; a Jaccard's genetic similarity matrix and a dendrogram for these cultivars were formed, in which they could be divided into four groups: Group 1 was composed of D. opposita. cv. Ribenbai, D. opposita. cv. Huashanyao and D. opposita. cv. Ribenyuan; Group2 contained D. opposita. cv. Xiaoye; Group 3 contained D. opposita. cv. No.1 Songye; other 23 cultivars were put into Group4. PCA(Principal component analysis) was employed to evaluate the resolving power of the markers to differentiate among them. This laid the foundation of the identification of yam cultivars and the efficient use of its germplasm resources.