西瓜种质资源遗传亲缘关系的RAPD分析

Analysis of genetic relationships of watermelon [Citrullus lanatus (Thunb.) Mansfeld] germplasm using random amplified polymorphic DNA (RAPD)

利用 RAPD 技术对国内外32份西瓜主栽品种与其骨干亲本及野生类型的遗传亲缘关系进行了研究。从720个随机引物(10bp)中筛选出15个能产生稳定多态性的引物用于 RAPD 反应,共扩增出104条 DNA 带,其中多态性 DNA 条带43条,占41.35%,平均每个引物扩增的 DNA 条带的数目为7.0条。聚类分析将供试材料分为6个类群:1个东亚生态型类群、1个美国生态型类群、2个中间生态型类群和2个非洲野生型类群,与传统的西瓜生态型分类基本吻合。每个生态型类群都有其特有的扩增(缺失)条带,同时分析了同一生态型中各个品种之间的亲缘关系及其品种的特异条带。本实验结果不仅从分子水平验证了西瓜是遗传基础狭窄的作物,而且在分子水平对西瓜传统分类与地理生态型分类进行了分析。

RAPD analysis was applied to assess the genetic relationships among 32 accessions of watermelon [Citrullus lanatus (Thunb.) Mansf.].Fifteen primers(2.08%) were screened from 720 arbitrary 10-mer primers,and a total of 104 bands were amplified, 43 of which (41.35%) were polymorphic.The average number of DNA bands amplified by each primer was 7.0.A dendrogram was constructed by using complete linkage method.The 32 accessions were assigned to six groups which were one East-Asia group, one American group,two medial groups and two African wild groups.Each ecological type group had its specific bands which were available to discriminate other groups.The results obtained by RAPD analysis were fundamentally identical with their origins and characteristics,and the genetic diversity in watermelon was narrow.