Genetic diversity of Centella asiatica in China analyzed by inter-simple sequence repeat (ISSR) markers: combination analysis with chemical diversity.

Centella asiatica is an important plant species used in traditional Chinese medicine. To help the efficient use and conservation of this species, the genetic diversity of C. asiatica populations in China was investigated using inter-simple sequence repeat (ISSR) markers. Fourteen natural populations comprising 162 individuals were included to estimate genetic diversity. At the species level, genetic diversity was relatively high (P = 66.33%, H = 0.2183, I = 0.3305). At the population level, the genetic diversity of JH (Jinhua, Zhejiang Province, China) and JJ (Jiujiang, Jiangxi Province, China) populations was relatively high (P = 43.88%, 38.78%, H = 0.1610, 0.1301, I = 0.2376, 0.1957, respectively), whereas the genetic diversity of GA (Guang'an, Sichuan Province, China) and EM (E'mei, Sichuan Province, China) was relatively low (P = 10.2%, 5.1%, H = 0.0383, 0.0211, I = 0.0570, 0.0309, respectively). On the basis of Nei's G(st) value, more genetic differentiation among populations was determined (G(st) = 0.6573). In addition, the 14 populations were clustered into four groups in view of abundant ISSR data, which further defined the genetic relationship among populations. Interestingly, the genetic clustering result was similar to previous chemical clustering results based on high-performance liquid chromatography (HPLC) data, which would also classify the 14 populations into four groups. Thus, we combined the clustering results and compared their difference. The combined analysis and genetic diversity data provide a scientific basis for conserving populations of relatively high genetic diversity such as JH and JJ populations and establishing good agricultural practices (GAP) for C. asiatica.