Genetic Diversity Analysis of Two Cephalotaxus Species

Using endosperm as material,allozyme gel electrophoresis technique was employed to analyze the genetic diversity of Cephalotaxus alpina and C.sinensis.The results showed that the genetic diversity levels of these two species were low,ratio of the polymorphic loci was 60 % and the average allele number per loci were 1.364 and 1.455 respectively,the average expected heterozygosity were 0.092 and 0.101,the average observed heterozygosity were 0.074 and 0.093,the inbreeding coefficient were 0.194 and 0.086 respectively,which implied that inbreeding was existed in these two Cephalotaxus plant species.Combing reporty studies on other species of Cephalotaxus,it is assumed that low genetic diversity is the reflection of endangered status of Cephalotaxus species.It is therefore suggested to list the plant species of Cephalotaxus as national key protected wild plants,with the expectation of strengthening the protection of Cephalotaxus plants.Besides,in this paper,the authors state that the inbreeding coefficient of Cephalotaxus species is positively correlated with the natural distribution scope,those species with smaller natural distribution areas show more serious inbreeding than those species with bigger natural distribution area.