中文摘要：

蓖麻（Ricinuscommunis L．）是一种重要的工业油源作物，具有多种经济价值．为了解蓖麻的遗传多样性，本研究对50份蓖麻种质的遗传多样性进行SRAP分析.结果表明50份种质之间多态性低，其多态条带比率、平均基因多样性和每对引物的多态性带，分别为29．97％、0．0904和5．41，遗传相似系数介于0．6469至0．9739之间，香农指数为0．1379；华北种质群比其它种质群的遗传变异相对丰富，而华南种质群的各种质则紧密地聚在一起．采用不加权算术平均组对法（UPGMA）将50份种质分为三大类群，与二维主成分分析（PCA）的结果相一致，一些来自相同地区的种质紧密聚在一起，表现出一定的地域性；7个种质群分别聚为两大类群．

英文摘要：

Castor bean （Ricinus communis L.） is a significant industrial oilseed crop and has the important economical value. With the aim of understanding the genetic diversity of castor bean germplasms, fifty accessions were investigated using sequence-related amplified polymorphism （SRAP） markers. The result indicated low polymorphic level among them, with only 29.97% percentage of polymorphic bands （PPB）, the average gene diversity and polymorphic bands per primer sets was 0.0904 and 5.41, respectively. The pair-wise similarity between germplasms was ranged from 0.6469 to 0.9739, Shannon＇ s information index was 0.1379. The results also suggested that the accessions from North China gave relatively plentiful genetic variation, and those from South China were assembled closely. Fifty accessions were divided into three major groups based on SRAP genetic similarity by the UPGMA method, which was consistent with the scatterplot result of principal coordinates analysis （PCA）, and some accessions from the same region or district were closely assembled together, suggesting a few geographic structuring of accessions across or within regions. Fur- thermore, seven populations were clustered into two groups with Popgene software.