Analysis Of Genetic Diversity Between Island And Mainland Natural Populations Of Polygonatum Odoratum In Dalian Area By ISSR

Polygonatum odoratumis widespread species of temperate Eurasia that belong to the Liliaceae family,it is widely distribute in Dalian,with edible and medicinal value.As an object of study and carried out comparison and analysis of genetic diversity of 262 Polygonatum odoratum from 5 islands and 4 mainland populations by ISSR molecular marker technology.Used the POPGENE 1.32 software to calculate the genetic data,genetic structure and genetic differentiation.Meanwhile,the genetic diversity of mainland population and island population was compared.The experimental results of this study are as follows:(1)120 genome bands are amplified by 10 primers.There are 110 polymorphic loci.The percentage of polymorphic bands was 91.67%,the gene diversity index of Nei’s(h)was0.3460 and Shannon information index(I)was 0.5108.It shows that Polygonatum odoratum has a higher genetic diversity.(2)In the 9 populations of Polygonatum odoratum,its genetic differentiation coefficient(Gst)was 0.1174.11.74% of the genetic variation occurred among populations.The genetic variation mainly occurred within population level.Its gene flow(Nm)was 3.7585.It shows that the gene flow between the populations is relatively frequent,it less affected by geographical distance.(3)According to the genetic distance of 9 Polygonatum odoratum populations,the UPGMA cluster analysis was obtained.The dendrogram consisted of four main clusters.SD and XHS are two independent clusters,XS and XPD are clustered into one cluster.Other populations form a cluster.The clustering result indicated that there is a correlation between the genetic relationship and geographical distribution of Polygonatum odoratum populations to some degree,but which isn’t the only dominant factor and it may be affected by human disturbance and climate showed that Polygonatum odoratum populations genetic relationship with geographical distribution has a certain degree of correlation,but not the only dominant factor.(4)By comparison between genetic diversity of populations from the mainland and islands,it was found that the genetic diversity of populations from islands was slightly higher than that from the mainland,indicating that under a more isolated ecological environment and more complicated selection pressure,populations of Polygonatum odoratum on islands might accumulate more genetic variation to form high levels of genetic diversity.The research results of this paper would provide evidence for further discussion on laws of genetic evolution of populations of natural plants in isolated ecological environments.This is the first comparative analysis on the genetic diversity of wild and cultivated Polygonatum odoratum populations in Liaoning province that use ISSR molecular marker technology.The characteristics of genetic diversity,genetic structure and genetic differentiation of wild Polygonatum odoratum population in different habitats of island and mainland were studied at the species level and population level.The results of this paper will provide evidence for further study on the genetic evolution of natural plant populations in isolated habitats.