Abstract: Six populations of Cypripedium flavum were studied on their genetic diversity, genetic structure, and clonal diversity in Zhongdian County , Yunnan Province (South-west China). Using POPGENE software, 86 polymorphic loci was obtained using two AFLP primer combinations, and the proportion of polymorphic loci was 82.69%. A relatively high level of genetic diversity was revealed: H_e = 0.2884 , H_o = 0.4312 ( at species level ) ; P = 64.59% , H_e = 0.2449 , Ho = 0.3606 ( at population level ). Genetic differentiation among populations was not high ( G_st = 0.154). A relatively high level of gene flow was obtained among populations. Clonal diversity of populations was high ( D = 0.9638 - 0.9960 , GN = 0.83 - 0.96), and ramets of same genotype were adjacent . C. flavum was found with high level of genetic diversity. This may be explained by gene heterozygosity increasing by seedling recruitment and maintaining by clonal reproduction .

Key words: Cypripedium flavum