Genetic Differentiation of Calycanthus chinensis an Endangered Plant

Genetic structures of 5 Calycanthus chinensis populations,located Qingliangfeng in Lin'an city Zhejiang Province,were analyzed by Using Inter Simple Squence Repeat(ISSR) molecular marker technique, to reved genetic differentiation of S.chinensis fine scale,and to provided a theoretical basis for protecting and restoring its germplasm resources.Using 12 primers,98 polymorphic loci from total 171 loci were detected in 100 individuals from 5 populations and the overall percentage of polymorphic loci(P) was 57.31% with an average of 25.03%.Total Shannon's information index(I) and Nei's gene diversity(h) of S.chinensis was the total value of 0.268 9、0.174 5 with an average of 0.148 8、0.102 8 respectively.The results of P,I and h indicated that genetic diversity at species level was relatively high,but at relatively low at population level.Analysis of molecular variation(AMOVA) suggested the variation was 47.01% among populations and 52.99% within population.Therefore,genetic differentiation within population and among populations were significant.The gene flow among populations was as low as 0.717 3 indicating that part of gene flow was blocked.The mean genetic distance of 5 S.chinensis populations was 0.105 1.Based on genetic distance,the clustered result for 5 S.chinensis populations by unweighted pair group method arithmetic average(UPGMA) suggested the populations in the similar habitat were clustered together.So genetic differentiation among S.chinensis populations was induced by its biological characteristic and the adaptability for different microhabitat.