Abstract: Four sets of rice isonuclear-alloplasmic lines including 16 male sterile lines and their maintainer lines were analyzed by using 91 pairs of SSR primers to study the genetic diversity of nuclear genome and their relative relationships. A total of 169 alleles were detected in the 16 lines, with a frequency of polymorphic loci of 53.85% and an average number of alleles per locus of 1.8, and the average gene diversity was 0.228. Four sets of the isonuclear-alloplasmic male sterile lines shared 146 identical alleles, corresponding to 86.39% of the total alleles; meanwhile, there are 23 different alleles among the tested materials, being 13.61% of the total alleles. On average, 78.70% identical alleles and 21.30% different alleles of the total alleles were detected between the isonuclear-alloplasmic male sterile lines and their maintainer lines. There were 53.85% identical alleles and 46.15% different alleles of the total alleles among the homozygous allonucleus male sterile lines. The fingerprints were established for some male sterile lines and maintainer lines. All the materials tested were divided into three groups at the 0.2 genetic distance based on the cluster analysis. Eight lines of Huanong A and Huayu A (including Huanong B and Huayu B) were in the first group, four lines of Kezhen A (including Kezhen B) in the second group, and four lines of Zhenshan 97A (including Zhenshan 97B) in the third group. For the isonuclear-alloplasmic male sterile lines, the similarity coefficient between Y (Yegong) type and WA (wild abortive) type or between CW (Raoping wild rice) and WA type reached 87-98%.

Key words: hybrid rice, isonuclear-alloplasmic male sterile line, maintainer line, genetic diversity