[Genetic diversity evaluation of cultivars (G. hirsumtum L.) from the Changjiang river valley and Tellow river valley by RAPD markers].

Forty-one polymorphic decamer primers with clear and repeated band pattern, which were screened out from 300 randomly selected primers, were applied to assess genetic diversity of cultivars (G. hirsumtum L.) from the Changjiang river valley and the Yellow river valley by RAPD analysis. Eighty-four polymorphic loci were obtained from 84 cultivars from the Changjiang river valley and 96 polymorphic loci were obtained from 68 cultivars from the Yellow river valley. Jaccard's genetic similarity coefficients were calculated using the software of NTSYS-pc version 1.80, and two dendrograms were constructed by the unweighted pair group method of arithmetic average (UPGMA). Mean similarity coefficient among cultivars from the Changjiang river valley was up to 0.631. And cultivars from the Yellow river valley had an average similarity coefficient of 0.632. Compared similarity coefficient matrices and frequency distribution of pairwise similarity coefficients, a conclusion was drawn that cultivars from the two areas had nearly the same level of genetic diversity. Same base germplasm, breeding objectives, breeding methods and strategy could be attributed to similar genetic diversity between the two areas.