ISSR Analysis of Genetic Diversity of Rubus niveus Thunb.Populations

Genetic diversity of 242 individuals from 12 natural populations of Rubus niveus Thunb.,was assessed using ISSR markers.The results showed that sixteen primers produced a total of 257 amplified fragments,of which 236(91.83%) are polymorphic.An extraordinarily high level of genetic diversity was showed in these populations.At species level,percentage of polymorphic loci PPB=97.50%,effective number of alleles(Ae) 1.267,Nei's gene diversity(H) 0.177,and Shannon's information index(I) 0.296.At population level,PPB=51.43%,Ae=1.205,H=0.127,I=0.202.The level of genetic differentiation between populations is lower than that within populations.The coefficient of gene differentiation(Gst) between the populations is 0.281 5,and the gene differentiation contributes to 34.47% of the total genetic variations between the populations and to 65.53% within the populations.The total gene flow(Nm) is 1.276 2.While the Mantel test showed no significant correlation between genetic and geographic distances among population(r=0.006 3,P=0.278 0).The results of UPGMA clustering analysis was basically identical with principle coordinate analysis(PCA).Jinshajiang(JSJ) population and Weixi(WX) population were clustered into one group.The other populations were clustered into another group in the dendrogram.The results indicated that populations with similar ecological and geographical conditions were clustered firstly.