OBJECTIVETo explore the genetic evolutionary distance between plants by using karyotype parameters identification of medicinal plants.

METHODThe cluster analysis of karyotype resemblance-near coefficient and evolutionary distance was used for 6 Bupleurum species.

RESULTThe results showed that there were the biggest karyotype resemblance-near coefficient (0.9920) and the smallest evolutionary distance (D(e) = 0.0080) between B. scorzonerifolium and B. chinense, indicating the closest relationship, and the minimum karyotype resemblance-near coefficient (0.4794) and the maximum evolutionary distance (D(e) = 0.7352) between B. smityii and B. falcatum, indicating the most distant relationship.

CONCLUSIONKaryotype was an important parameter for identification of medicinal plants because karyotype was stabilized for species. The genetic distance between in 6 species of Bupleurum species was obtained by karyotype clustering analysis of karyotype resemblance-near coefficient. There was the bigger evolutionary distance between the species which had different chromosome number.