[Genetic diversity of Polygonum capitatum from Guizhou populations by ISSR markers].

Objective: To detect genetic diversity of 48 population of Polygonum capitatum in Guizhou province.

Method: The genetic diversity of 48 representational populations of P. capitatum including 240 individuals had been investigated by ISSR marker technique.

Result: The genetic diversity had been revealed as follow: A total of 8 293 bands were produced in 240 individuals, of which 7 962 bands were common in the 48 population. The value of the average percentage of polymorphic bands (PPB) was 79.09%, Nei's genetic diversity index (H(e)) was 0.245 8, Shannon's information index (I) was 0.396 2, and genetic differentiation index (G(st)) was 0.238 0 at population level, respectively. The genetic differentiation index (G(st)) was 0.072 2, genetic differentiation coefficient by Shannon's diversity (I(st)) was 0.044 2 within the population levels. Groups cluster analysis based on the UPGMA method indicated that although the 48 populations could be divided into 3 groups and the P. capitatum seed sources. The groups cluster showed that a cross clustering of P. capitatum between the southwest and southeast populations in Guizhou province, and no significant correlation was found between geographical and genetic distance among them.

Conclusion: The genetic diversity of P. capitatum is relatively high at the population levels, while low within the population levels, a significant degree of genetic differentiation occurs among the populations. The groups cluster analysis indicated they has not apparent genetic variation in regional pattern between the place of origin populations and the migrate populations.