Abstract: The genetic diversity was analysed in 53 rice cultivars with resistance to bacterial blight by RAPD. Twenty random primers were selected from 90 ones screened. Results showed that these cultivars exhibited extensive genetic variability and abundant genetic diversity. Cluster analysis based on DNA data revealed that there were significant differences between the resistant and susceptible cultivars. Fifty one of them could be divided into 13 groups, Group 1,2, and 5 were predominant, including 8,17, and 9 cultivars, respectively. Thus the genetic characteristics of rice clusters showed bacterial blight resistance, it may be useful in rice breeding for developing resistant cultivars to control the disease.

Key words: rice, bacterial blight, genetic diversity, resistance, random amplified polymorphic DNA

摘要： 利用RAPD技术，从90个RAPD引物中筛选出20个引物，通过PCR扩增，对53份抗白叶枯病水稻品种进行遗传多样性分析。结果表明，供试的水稻品种间遗传分化明显，具有丰富的遗传多态性。经聚类分析可知，抗病品种与感病品种遗传差异很大，很容易区分开，在遗传距离为0.2时，测试的51个抗白叶枯病水稻品种可分为13个遗传相似组，其中1、2、5组为主要主群，分别包括8个、17个和9个品种。

关键词: 水稻, 白叶枯病, 遗传多样性, 抗性, 随机扩增多态性DNA