Clonal Diversity and Genetic Differentiation of Endangered Liana Species Monimopetalum chinense (Celastraceae) in Poyang Lake Basin

摘要

In the present study, clonal diversity and genetic differentiation of endangered liana species Monimopetalum chinense populations in Poyang Lake basin were studied by using inter-simple sequence repeat (ISSR) markers. According to the results, the effective conservation measures were produced. The results indicated that the population has high clonal diversity (D = 0.9969). In addition, there was great clonal differentiation among populations with no widespread genotyes. Genetic variation at the species level or at the population level are all lower (species level: PPB = 39.2%, HT = 0.129; Populations level: PPB = 15.64%, HS = 0.0557) than that of most other clonal plants. Strong genetic differentiation among populations was detected in M. chinense, with 49.06% of total genetic variation (AMOVA, Analysis of molecular variance), 0.5672 of Nei's gene differentiation coefficient (GST) and 0.5464 of Shannon information index. The population fragmentation since the end of Tertiary period, genetic drift of small population size and the form of inbreeding reproduction would have contributed to such genetic differentiation among populations of M. chinense. Based on these findings, it was suggested that these populations with relatively high genetic diversity should be protected in situ whereas simultaneously raising public awareness of this rare species, so that the genetic diversity of M. chinense could be conserved effectively.