基于荧光SSR标记的紫薇遗传多样性分析

【目的】以收集的239份紫薇属(Lagerstroemia)种质和1份黄薇属(Heimia)种质为材料，开展种质种间特征分析和紫薇种内资源的遗传多样性分析，为进一步优化紫薇种质资源收集保存及合理利用提供科学依据。【方法】基于16对荧光引物鉴定样品基因型，利用GeneMarker软件进行基因型数据的读取；对239份紫薇属种质和1份黄薇属种质进行特征位点分析；并利用Popgene、Cervus、NTSYS和GenAlEx软件对227份紫薇种质进行遗传多样性参数估算、聚类分析和主成分分析。【结果】紫薇(L.indica)种内的特征位点信息最为丰富，其中15个引物所体现出的特征位点信息中，紫薇都有其独特的位点区别于其他6个种，而在福建紫薇(L.limii)、川黔紫薇(L.excelsa)和尾叶紫薇(L.caudata)中也有部分特异的特征位点是紫薇中没有的；16对紫薇SSR荧光引物共检测出143个等位基因，平均每个位点有8.938个等位基因，平均有效等位基因数(N_e)为3.600,Shannon’s信息指数(I)均值为1.459,观测杂合度(H_o)均...

Genetic diversity analysis of Lagerstroemia indica based on fluorescent SSR markers

【Objective】 In this study, 239 germplasms of Lagerstroemia and one germplasm of Heimia were used to analyze the interspecific characteristics and genetic diversity of germplasm resources within L. indica, providing a scientific basis for collection, conservation and rational utilization of germplasm resources.【Method】 Genotypes of samples were identified based on 16 pairs of fluorescent primers; genotypes were read by the GeneMarker software. The characteristic loci of 239 germplasms of L. indica and one germplasm of H. myrtifolia were analyzed. The POPGENE, Cervus, NTSYS and GenAlEx software were used to estimate genetic diversity parameters, the cluster analysis and principal corrdinate analysis of 227 L. indica germplasms. 【Result】 Characteristic loci information of L. indica was the most abundant. Among the characteristic loci information reflected by 15 primers, L. indica all had unique loci that were different from the other six species, and some specific characteristic loci were not found in L. limii, L. excelsa and L. caudata. A total of 143 alleles were detected by 16 pairs of SSR(simple sequence repeat) fluorescent primers; there was an average of 8.938 alleles per locus and the average number of alleles per locus (N_e) was 3.600; Shannon’s Information Index (I) was 1.459, the average observed heterozygosity (H_o) was 0.577, the average expected heterozygosity (H_e) was 0.687, the average value of Nei’s genetic diversity index (H) was 0.685, and the average polymorphism information (PIC) in primers was 0.648. From the genetic diversity of 227 L. indica. based on the genetic distance between samples, a genetic cluster map was drawn and the samples were divided into 10 groups. The L. indica germplasm introduced from United States and wild L. indica germplasm from Hubei were relatively independent and clustered into different groups. The cluster analysis showed that L. indica germplasms were divided into 10 groups, among which the imported L. indica germplasm from the United States and the wild L. indica germplasm from Hubei were clustered into different groups. The principal corrdinate analysis showed that the 10 groups could be roughly divided into three regions, among which the wild L. indica germplasm from Hubei Province and the germplasm introduced from the United States were relatively clustered together.【Conclusion】 SSR markers can effectively reflect genetic diversity among L. indica germplasm resources, and can further optimize the collection and preservation of L. indica germplasm resources, build the core germplasm, create new varieties and provide a scientific basis for the rational development and utilization.