Abstract: Hepatacodium miconioides is the Class II protected plant species in China.This paper studied the genetic diversity and differentiation of its nine natural populations in Zhejiang Province by using random amplified polymorphic DNA (RAPD) technique.Twelve random primers were selected in the amplification,and 164 repetitive loci were produced.The percentage of polymorphic loci in each H.miconioides population ranged from 14.60% to 27.44%,with an average of 20.73%.Among the test populations,Kuochangshan population had the highest percentage of polymorphic loci,Simingshan population took the second place,and Guanyinping population had the lowest one.As estimated by Shannon index,the genetic diversity within H.miconioides populations accounted for 27.28% of the total genetic diversity,while that among H.miconioides populations accounted for 72.72%.The genetic differentiation among H.miconioides populations as estimated by Nei index was 0.7157.The genetic differentiation estimated by Nei index was generally consistent with that estimated by Shannon index,i.e.,the genetic differentiation among populations was relatively high,but that within populations was relatively low.The gene flow among H.miconioides populations was relatively low (0.1987),and the genetic similarity ranged from 0.6557 to 0.8119,with an average of 0.7306.The highest genetic distance among populations was 0.4229,while the lowest one was 0.2083.All the results showed that there was a distinct genetic differentiation among H.miconioides populations.The genetic distance matrix of nine test populations was calculated by using the method,and the clustering analysis was made by using the unweighted pair group method with arithmetic mean (UPGMA).The cluster analysis suggested that the nine populations of H.miconioides in Zhejiang Province could be divided into two groups,i.e.,eastern Zhejiang group and western Zhejiang group.

Key words: Hepatacodium miconioides, Natural population, Genetic diversity, Genetic differentiation, RAPD