Analyses of genetic diversity and genetic relationship of eight populations of Malus baccata based on SSR marker

PCR amplification of total genomic DNA from 140 individuals of eight populations of Malus baccata(L.) Borkh.was carried out by using ten pairs of SSR primers,and hereby,their genetic diversity and genetic relationship were analyzed.The results show that there are totally 91 bands amplified by ten pairs of SSR primers and percentage of polymorphic band is 100.00%.The difference of genetic diversity parameters of eight populations is great,and effective number of allele is 1.437 9-1.535 0,Nei's gene diversity index is 0.256 0-0.309 2,Shannon information index is 0.376 7-0.459 2,percentage of polymorphic band is 64.84%-85.71%.The effective number of allele,Nei's gene diversity index and Shannon information index among eight populations are 1.616 9,0.355 1 and 0.528 5,respectively,which is obviously higher than those within population.The gene flow and gene differentiation coefficient of eight populations are 1.739 5 and 0.223 3,respectively,indicating that the gene exchange among populations is more.The result of UPGMA cluster analysis shows that eight populations of M.baccata are divided into three groups where Nei's genetic distance is 0.148 6.In which,the population in Saihanba of Hebei Province is a group individually,two populations in Mt.Wutai of Shanxi Province and Mt.Dongling of Beijing City are a group,the other five populations are a group.Based on these results,it is presumed that M.baccata is originated from the North and Northeast of China,M.baccata populations in Mt.Lingkong of Shanxi Province,Xiaoxing'anling of Heilongjiang Province,Mt.Changbai of Jilin Province and Mt.Zhongtiao of Shanxi Province may be core populations of genetic diversity.