不同居群朱砂根(Ardisia crenata)的荧光ISSR遗传多样性分析

Genetic Diversity Analysis of Ardisia crenata in Different Populations by Fluorescence ISSR

为了从分子水平揭示福建省不同野生居群朱砂根的遗传多样性水平,本研究采用荧光ISSR分子标记对福建省20个朱砂根野生居群共255个样株的遗传多样性及遗传结构进行了分析。5条ISSR荧光引物共扩增出谱带为186条,其中多态性谱带为96条,多态性平均百分率达到55.77%。居群的多态位点百分比(PPL)在37.65%~80.39%之间,观测等位基因数(Na)在1.3765~1.8039之间,Shannon指数在0.2000~0.3672范围内,Nei’s基因多样度(H)于0.1256~0.2425之间、有效等位基因数(Ne)为1.1923~1.4079,以上数据表明朱砂根居群遗传多样性较丰富。居群间的遗传变异(Dst)为0.0592,小于居群内遗传变异(Hs)。居群间的基因流为1.4335(>1),具有较高的基因流动。不同居群的遗传一致度于0.6201~0.9782之间,遗传距离于0.0242~0.559范围内,证明了朱砂根各居群间的亲缘关系接近。对遗传距离与地理距离进行Mantel相关性分析发现无显著相关性。通过对朱砂根各居群样株进行主坐标分析,发现居群间亲缘关系远近和地理分布规律无较明显的相关性,但居群间基因流动较密切,且具备一定程度的遗传分化,并依据Structure遗传结构分析,把居群划分为两大类的结果与主坐标分析相似,且居群间存在较高的遗传渗透。本研究为今后构建朱砂根资源核心种质库,优良性状种源的筛选与储存、引种及驯化及种群保护策略的制定及新资源的开发提供相关的理论依据。

To reveal the genetic diversity of Ardisia crenata from different wild populations in Fujian Province at the molecular level,the genetic diversity and genetic structure of 255 samples from 20 wild populations of Ardisia crenata in Fujian Province were analyzed by fluorescence ISSR molecular markers.A total of 186 bands were amplified by 5 ISSR primers,of which 96 were polymorphic,and the average percentage of polymorphic bands reached 55.77%.The percentage of polymorphic loci(PPL)ranged from 37.65%to 80.39%,the observed allele number(Na)ranged from 1.3765 to 1.8039,Shannon index ranged from 0.2000 to 0.3672,Nei’s gene diversity(H)is between 0.1256 and 0.2425,and the effective allele number(Ne)ranged from 1.1923 to 1.4079,the above data indicate that the genetic diversity of Ardisia crenata population is relatively rich.The genetic variation among populations(Dst)was 0.0592,which was less than the genetic variation within populations(Hs).The gene flow among populations was 1.4335(>1),which showed high gene flow.The genetic identity of different populations ranged from 0.6201 to 0.9782,and the genetic distance ranged from 0.0242 to 0.559,which indicated that the genetic relationship among the populations of Ardisia crenata was close.By comparing Mantel correlation between geographic distance and genetic distance among populations,it was found that there was no significant correlation.Through principal coordinate analysis of sample plants of Ardisia crenata,it was found that there was no obvious correlation between genetic relationship and geographical distribution,but there was close gene flow among populations and genetic differentiation to a certain extent.According to Structure genetic structure analysis,the results of dividing populations into two categories were similar to principal coordinate analysis,and there was high genetic penetration among populations.This study provides relevant theoretical basis for the construction of core germplasm bank of Ardisia crenata resources,the selection and storage,introduction and domestication of provenances with excellent traits,the formulation of population protection strategies and the development of new resources.