[Polymorphisms in semilate indica hybrid rice as revealed by AFLPs]

The polymorphisms were analyzed in 15 semilate indica parental materials with AFLPs. The genetic distances between parental materials were small with an average of 0.2033, ranged from 0.0589 to 0.3913. Fifteen parental materials were classified into two groups,cytoplasmic male-sterile lineIand restorer line II. The latter were classified into two subgroups, II-1 and II-2. SubgroupII-2 was consanguinity with Minghui63. The genetic distances between male-sterile line and two restorer line subgroups(II-1 and II-2) did not show significant difference, indicating that the genetic bases of restorer lines were similar,which maybe one of major reasons for the yield still not surpassing Shanyou63 in indica hybrid rice presently. To increase the heterosis of hybrid rice, we must enrich the genetic diversity and expand the genetic differences between parental lines.