Study On The Genetic Diversity Of Wild Gleditsia Sinensis Resources In Guizhou Provinc

Gleditsia sinensis Lam.is a tall deciduous tree of the genus Gleditsia of the Leguminosae,is an ecological economic tree species in China and widely distributed.As a distribution area of ??wild G.sinensis locust resources,Guizhou Province is planting fruit(seed)in a large area.The genetic diversity analysis and evaluation of wild G.sinensis locust resources can provide a basis for the rational development and utilization of germplasm resources.To this end,this study took the wild G.sinensis population naturally distributed in Guizhou Province as the research object,and used morphological traits,physiological and biochemical and SRAP molecular markers to analyze the genetic diversity of the G.sinensis population,in order to provide a basis for the collection and preservation of G.sinensis germplasm resources in Guizhou Province,and based on the cultivation target of "seed use" to screen the excellent germplasm of G.sinensis,to providing materials for the development and utilization of G.sinensis resources.The main research results were as follows:(1)Study on seed and seed morphological traits of G.sinensis: the average coefficient of variation among various morphological traits of G.sinensis was 21.16%,and the variation of podwas higher than that of seed,among which kaili population had the most abundant variation.The genetic diversity of seed and seed morphology of G.sinensis was high,and the variation came from the population.Correlation analysis showed that there was a certain correlation among various solid morphological traits of G.sinensis.With the increase of altitude,the larger the pod morphological index was,the smaller the seed morphological was;the older the tree age,the higher the pod shape and seed production rate;From south to north and from east to west in Guizhou province,the seeds have a trend of increasing gradually.On the basis of principal component analysis,based on the cultivation of G.sinensis "seed",the comprehensive performance of Huishui provenance was selected,and the average value of each trait was higher than the overall average.G.sinensis single plant for breeding improvement work.(2)Analysis of physiological characters of G.sinensis: The physiological characters of catalase,peroxidase,soluble sugar,soluble protein,chlorophyll and carotenoid of 14 G.sinensis populations in Guizhou Province were measured,and the average value of each character was 1327.656 nmol./min/g,5231.416 μ/g,5.613 mg/g,16.382 mg/g,3.94 mg/g,2.14 mg/g;The variance analysis showed that the analysis indexes of other physiological and biochemical traits reached significant levels among and within populations,except the soluble sugar content and peroxidase activity(P < 0.05).The correlation analysis showed that the catalase activity,peroxidase activity and photosynthetic pigment of the G.sinensis collected in Guizhou province increased from south to north and from east to west.According to the K-means clustering method,14 groups were clustered into 4 categories;according to the measured mean values ??of different physiological traits,groups with stronger stress resistance were selected to provide basic materials for the selection of excellent trees and the cultivation of good varieties of G.sinensis.(3)Screening of SRAP primers and genetic diversity index of G.sinensis: 10 pairs of SRAP primers were selected from 169 pairs of primer combinations,which can be used for the study of the genetic diversity of G.sinensis.A total of 77 bands were amplified,including76 polymorphic bands and 1895 polymorphic loci,with an average polymorphism percentage of 98.70%.Using POPGENE 32 software to analyze the total genetic diversity Ht=0.3688,Hs=0.2755,Gst=0.2530 of 14 populations of G.sinensis,indicating that the genetic variation mainly comes from within the population;the gene flow Nm is 1.4764,indicating that the gene flow among the G.sinensis populations is on the upper middle side,and the exchanges are more frequent.(4)Genetic relationship and cluster analysis of G.sinensis locust: The genetic distance of14 groups of G.sinensis locust is between 0.0504 and 0.3596,with an average value of0.1616,and the variation range of the genetic similarity coefficient of the population is between 0.7261 and 0.9508,with an average value of 0.8635;using NTSYS-pc2.10 e software can divide 14 groups into 5 categories at the similarity coefficient of 0.886.There was a significant positive correlation between genetic distance and geographic distance between populations.