Genetic diversity of Ligusticum chuanxiong Hort. based on inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) analyses

Abstract

Ligusticum chuanxiong Hort. (Apiaceae) is a well-known traditional Chinese medicinal herb with hemodynamic and analgesic effects. The species is known to undergo strict asexual reproduction via clonal propagation, and all known occurrences of the species are under cultivation practices. In this study, genetic diversity of L. chuanxiong throughout most of its cultivated range in China was assessed. Two hundred and sixty-six individuals representing 14 populations of L. chuanxiong were screened for ISSR and AFLP markers. ISSR analysis detected polymorphisms in 35% of the observed bands generated from 10 primer pairs. Two hundred and fifty-six AFLP fragments were obtained with six primer combinations, with a 29.3% level of polymorphism. These results indicated low levels of genetic variation in cultivated populations. Independent UPGMA analyses were performed for ISSR and AFLP data. The dendrograms generated from both data sets  showed a close alliance among Sichuan Province populations, and Mantel tests revealed the presence of a moderate spatial geographic gradient among all populations representing five Provinces. Overall, our results suggested that mating system and anthropogenic effects play an important role in shaping the genetic diversity and structure of L. chuanxiong.

Key words: Ligusticum chuanxiong Hort., Genetic diversity, inter simple  sequence repeat, amplified fragment length polymorphism.