Abstract: Cypripedium japonicum is a rare and endangered terrestrial orchid. To explore and formulate the pertinent conversation strategies of this species, this paper analyzed the genetic diversity and genetic structure of six natural C. japonicum populations in Zhejiang Province of East China by the method of AFLP. A total of 377 distinct bands were amplified by 7 pairs of selected primers. The percentage of polymorphic loci was 20.95%, Nei’s genetic diversity index was 0.0512, Shannon information index was 0.0417, genetic differentiation coefficient was 0.5178, and gene flow was 0.4655, indicating that there was a relatively low genetic diversity within the C. japonicum populations, and a certain degree of genetic divergence  existed among the populations. The analyses of UPGMA clustering and Mantel test showed that there was no significant correlation between the geographical distance and genetic distance (r=0.16, P=0.242). Some conservation strategies were proposed based on this study and the biological properties of C. japonicum.

Key words: annual greenhouse gas emission, nitrification inhibitor, paddy field., controlled release urea