Abstract:Using the 24 SSR markers recommended by “Sector Standard of Agriculture (NY/1433-2077)”, this study analyzed the DNA fingerprint and genetic diversity of the 49 rice varieties (the example varieties listed in Rice DUS Test Guideline). The results showed that, 141 and 156 alleles could be amplified by the 24 SSR primers in 19 indica rice varieties and 30 japonica rice varieties respectively, meaning each pair of primers can amplify 5.88 alleles (indica rice) and 6.50 alleles (japonica rice).The average shannon’s diversity indexes of the 24 SSR primers were 1.5141 (1.0406-1.9959) and 1.4389 (0.4677-2.4503) for indica and japonica group respectively.Based on the results of cluster analysis, the similarity coefficient of varieties within indica and japonica rice group were 0.45-0.81 and 0.36-0.76 respectively, and 19 varieties of indica rice and 30 varieties of japonica rice could be sorted into 16 sets and 28 sets respectively using similarity coeffecient of 0.72 as threshold. Thus, the genetic diversity of the 49 rice varieties is rich. Based on the consideration of cluster analysis of morphological characteristics (previous results) and genetic diversity, the number of example varieties used in Rice DUS test could be reduced from 49 to 46.