Genetic Diversity and Ex Situ Conservation of Sinocalycanthus chinensis

Sinocalycanthus chinensis, a deciduous shrub of Calycanthaceae, is an endangered species endemic to eastern China. ISSR markers were applied to investigate the genetic diversity of natural populations and the ex situ population, so as to evaluate the efficiency of ex situ conservation. The percentage of polymorphic bands (PPB) for natural population and ex situ population of S. chinensis was 63.86 and 57.83% respectively, the Nei's gene diversity (h) 0.1713 and 0.1727, and the Shannon diversity index (I) 0.2687 and 0.2668. AMOVA showed that 31.21% of genetic variation occurred among natural populations, indicating genetic variation mainly existed within population. T-test revealed that the genetic diversity levels were not significantly different between natural populations and the ex situ population (p>0.01), suggesting the effectiveness of ex situ population for conserving genetic diversity of the plant species. The sampling strategy for ex situ genetic conservation was also discussed.