SSR genetic diversity of cold-tolerant native rice varieties in Guizhou.

Guizhou native cold-tolerant rice cultivars and rice 4 contrasts were analyzed by SSR with 16 markers ,the results showed that 16 markers produced 95 bands ,of which 70 were polymorphic ,the diversification was from 4 to 12,the average number of alleles per locus was 5.9,the percent of effective alleles and polymorphic locus were 75.8 % and 38 %,respectively .The genetic distances (GDs) were then used to construct a dendrogram by Neighbor Joining Method (NJ).The result showed that 15 rice varieties could be divided into Indica group and Japonica group, the latter were classified into three subgroups. The genetic distance in Japonica group and Indica group were 0.06-0.53 and 0.297-0.377,respectively, in addition,the genetic distance in Guizhou cold-tolerant rice varieties was 0.21-0.46, the genetic diversity was rich in Guizhou native cold-tolerant rice varieties belonging to Japonica group.Using SSR data and NJ to construct a dendrogram of those cultivars whose cold-tolerant ability were stronger during different growth period , the result indicated that the position of all cultivars was variational in the dendrogram, but the affinity was changeless.