Evaluation of the genetic diversity of Bupleurum using amplified fragment length polymorphism analysis

Radix bupleuri (Chaihu), the dried root of the Bupleurum plant, is an important component of traditional Chinese medicine. In this study, we examined the genetic diversity of 11 Bupleurum strains, originating from 7 provinces in China, using amplified fragment length polymorphism analysis. A total of 274 polymorphic bands were obtained using 6 primer combinations, indicating a high level of polymorphism across all strains. An estimation of the relative relationships among strains revealed genetic distances ranging from 0.2183 to 0.7372, with an average of 0.4161. The 2 most closely related varieties were Bupleurum chinense DC. strains collected from Lushi, Henan, and Zhangjiakou, Hebei, with a genetic nearness of 0.2183. Hierarchical clustering divided the strains into 3 main groups, with B. falcatum L. from Hebei and Liaoning Provinces forming a cluster that diverged from that of B. smithii Wolff. and B. chinense DC. B. falcatum L. (Sandao chaihu), collected from Heze, Shandong, clustered independently of the other strains, suggesting that this strain may have been introduced from a different location or that it arose as a result of intraspecific variation. B. smithii Wolff. (Hei chaihu) was closely associated with B. scorzonerifolium Willd. (Nan chaihu) and B. chinense DC. (Bei chaihu), suggesting a common genetic origin.