Study On Genetic Diversity Of Wild European Plum In Xinjiang

Xinjiang wild European plum(Prunus domestica L.),commonly known as wild sour plum,belongs to the Rosaceae Prunus.It is only distributed in the Yili region of Xinjiang.It is a precious and endangered wild fruit tree resource.The inversion is weak and the distribution area is small.In recent years,wild European plum resource has been severely damaged,and the population has been decreasing year by year.The current situation is not optimistic.In this study,83 germplasm resources of five wild populations of Gailiangchangsandui,Jiaowutuohai,Bolesai,Tiekuanggou and Yiligedai generation were taken as the research objects.ISSR and SSR molecular markers were used to analyze genetic diversity and genetic structure in order to provide scientific basis for the collection,protection and utilization of wild European plum germplasm resources.The main findings are as follows:(1)The phenotypic characteristics of five wild European plum populations were analyzed.The study found that the phenotypic diversity of Yiligedai population was relatively rich,and the phenotypic diversity of Bolesai population was relatively small.The phenotypic differentiation coefficient of different phenotypic traits in the five populations was between 3.35%and 48.22%.The variation coefficient of each phenotypic trait was between 1.36%and 16.28%,and the genetic stability of the phenotypic traits of flowers was better.While the genetic stability of branches and leaves was relatively poor.According to the principal component analysis,among 28 phenotypic traits,petal length,ovary width,leaf width,left vein number,anther length,leaf shape,right vein number,area per leaf,petiole length,petal width,pedicel length and number of petal were important indicators for evaluating the phenotypic diversity of wild European plum.(2)Genetic diversity analysis was performed on wild European plum using ISSR molecular markers.A total of 172 loci were amplified with 16 primers,and the percentage of polymorphic loci(PPI)was 43.02%.Nei’s gene diversity index(H)and Shannon information index(I)were 0.1546 and 0.2327,gene diversity(Hs)in the population was 0.1151,gene diversity(Ht)in the total population was 0.1806,and genetics among populations.The differentiation coefficient(Gst)was 0.3627 and the gene flow(Nm)was 0.8654,indicating that the genetic diversity of wild European plums in Xinjiang is not abundant,and the genetic variation mainly exists in the population.Based on the genetic distance(GD)clustering map,it could be seen that the genetic relationship the between Gailiangchangsandui population and the Jiaowutuohai population is closest,and the genetic distance(GD)is farther from the Yiligedai population.Among the 5 wild European plum populations in Xinjiang,the genetic diversity of Yiligedai population was higher.(3)Genetic diversity analysis of wild European plum was performed using 10 pairs of SSR primers,and a total of 109 loci were amplified.The percentage of polymorphic loci(PPI)was 28.44%,and the number of effective alleles(Ne)was 1.1975.Nei’s gene diversity(H)was 0.0912 and Shannon information index(I)was 0.1524.Gene diversity analysis showed that the Tiekuanggou population had the lowest diversity and the Yiligedai generation had the highest population.Xinjiang wild European plum has low genetic diversity and high genetic differentiation within populations.(4)Through the analysis and comparison of three marker methods,it is found that ISSR marker has high detection ability in the study of genetic diversity of wild European plum.The results of three marker analysis were almost the same,which showed that the genetic diversity of wild European plum was not rich,and its variation mainly came from the population.However,Yiligedai population has high genetic diversity,so it can be preferentially selected for conservation and utilization.