Study On The Genetic Diversity Of Bermudagrass(Cynodon Dactylon(L.) Pers.) Germplasm Resources In Henan Province

In this study,wild bermudagrass(Cynodon dactylon(L.)Pers.)collected from 15 populations in different areas of Henan Province was used as the research material.The combination of phenotypic traits and SSR molecular markers were used to analyze the genetic diversity of the bermudagrass population.The results of this study can provide a theoretical reference for the development and utilization of wild bermudagrass germplasm resources in Henan Province.The research results are as follows:(1)The results of genetic diversity analysis of bermudagrass populations based on phenotypic traits showed that the coefficients of variation of each tested trait from the highest to the lowest were turf height>stolon leaf length>internode length of stolon>leaf length of the erect shoot>stolon leaf width>leaf width of the erect shoot>internode diameter of stolon,with an average coefficient of variation of 32.85%.The average variation coefficients of the phenotypic traits of the 15 populations are different.The average variation coefficient of the P11(Xichuan)population is the largest(30.57%),and the P2(Puyang)population is the smallest(23.38%).The internode length of stolon and turf height were extremely different among the 15 populations,and there were significant differences in the stolon leaf length and leaf length of the erect shoot.The stolon leaf length and leaf length of the erect shoot and turf height are very different in the population,and the internode length of stolon are significantly different in the population.The stolon leaf width and leaf width of the erect shoot and internode diameter of the stolon were not significantly or very significantly difference between and within the population;the variance component within the population was greater than the variance component between the populations,indicating that the variation within the population was phenotypically inherited the main source of variation;6 pairs of phenotypic traits are extremely significantly correlated,4 pairs of traits are significantly correlated;leaf width of the erect shoot is significantly negatively correlated with annual precipitation;stolon leaf width is significantly negatively correlated with annual precipitation;stolon leaf width and leaf width of the erect shoot were significantly positively correlated with latitude;The cluster analysis of 15 bermuda populations was carried out,and the 15 populations were divided into 4 groups at the similarity coefficient of 0.028.The results showed that the geographically similar populations did not completely cluster together.The Mantel test between distance and genetic distance showed that the correlation between the two was not significant.The genetic distance matrix between populations based on phenotypic traits showed a very significant positive correlation with the latitude matrixand a significant negative correlation with the annual precipitation matrix,there is no correlation between genetic distance and other environmental factors.(2)The results of genetic diversity analysis of bermudagrass populations based on SSR markers showed that 288 bands of the tested materials amplified a total of 162 bands,the average number of amplified bands per primer pair was 16.2,and the polymorphic bands were 155,the polymorphism ratio is 95.68%;the average observed allele number(Na)is 1.5061,the average effective allele number(Ne)is 1.3183,the average Nei’s gene diversity index(H)is 0.1688,and the average Shannon’s the genetic diversity information index(I)was 0.2775;the results of genetic differentiation coefficient and gene flow analysis showed that 15 bermudagrass populations had large genetic differentiation,and genetic variation mainly existed in the population,which was similar to the analysis result of phenotypic genetic variation consistent.The average genetic consistency of 15 populations is 0.767,and the average genetic distance is 0.270.At the genetic consistency of 0.71,the bermudagrass of 15 populations can be divided into two groups.Mantel test results showed that there was no significant correlation between the geographic distance and genetic distance between populations.