Abstract: Glyptostrobus pensilis is a rare and endangered species in China, but few studies have been made on the conservation genetics of this species. In this study, the G. pensilis population in Pingnan of Fujian Province, East China was divided into 3 life stages, i.e., adult, juvenile, and seedling, according to the size class, and the genetic diversity and genetic differentiation of different life stage G. pensilis were investigated by using intersimple sequence repeat (ISSR) markers. Ten ISSR primers were used to amplify 72 individuals in the population, and 83 discernible DNA fragments were produced, of which, 32 were polymorphic loci (the percentage of polymorphic loci (P) = 38.55%), suggesting the low level genetic diversity of the population. The difference of the genetic diversity among the life stages was evident. Adult had the highest P, Nei’s gene index (H_e), and Shannon information index (I), followed by juvenile, and seedling, suggesting that the genetic diversity among the life stages presented a declining trend. The analysis of molecular variance (AMOVA) showed that the genetic diversity might exist within and among the life stages, mainly within the life stages. Moreover, the genetic differential index (G_st) among the life stages was 0.2872, while the gene flow (N_m) was 0.6203. The genetic identity between seedlings and juveniles was the highest. Based on the analysis of population genetic structure and the community investigation, it would be necessary to establish a conservation site in the optimal habitat of G. pensilis and to crosstransplant adult plants and seedlings mutually to enhance the gene flow. By this means, the genetic diversity resources of the species could be preserved to the greatest extent.

Key words: drought, rice, wetness index anomaly rate, distribution characteristic, Southwest China.