贵州黔西南烟草中辣椒脉斑驳病毒的鉴定及遗传多样性分析

Identification and genetic diversity analysis of chilli veinal mottle virus isolates from tobacco plants in southwest Guizhou

为明确贵州黔西南烟草中辣椒脉斑驳病毒(chilli veinal mottle virus,ChiVMV)的遗传多样性和分子进化特征,本研究以2021—2022年采集自贵州省黔西南州兴义市的52份疑似感染ChiVMV的烟草样品为实验材料,利用马铃薯Y病毒属(Potyvirus)通用引物和ChiVMV特异性引物进行RT-PCR检测、克隆和测序,并结合GenBank中已公布的相关序列对分离获得的16个ChiVMV贵州烟草分离物进行基于外壳蛋白(coat protein,CP)CP基因的遗传多样性和分子进化分析。结果显示,所获得的ChiVMV贵州烟草分离物与GenBank中其他36个分离物CP基因的核苷酸一致性为84.79%~99.65%;基于ChiVMV CP基因的系统进化分析发现,52个不同来源的ChiVMV分离物在进化上可以聚为3个不同的分支,聚类结果具有明显的地理分布特征;遗传多样性和进化分析结果表明,各群体受到地理分布的影响而表现出较高的遗传多样性,各群体间的遗传分化显著且基因交流频率较低。研究结果为ChiVMV抗病品种的选育和该类病毒病的防治具有重要意义。

To analyze the genetic diversity and molecular evolution characteristics of chili veinal mottle virus(ChiVMV)in Guizhou tobacco,52 tobacco samples suspected to be infected with ChiVMV in this study were collected from Xingyi City,Southwest of Guizhou Province in 2021-2022.The tobacco samples were detected by RT-PCR using universal primers for detection of Potyvirus,and the derived fragments were cloned and sequenced by ChiVMV specific primers.The genetic diversity and molecular evolution of 16 ChiVMV Guizhou isolates from tobacco were analyzed basing on the sequences of coat protein(CP)gene and related sequences reported in GenBank.The results showed that the nucleotide sequence identity between CP genes of the obtained ChiVMV Guizhou isolates and those of the other 36 isolates in GenBank was 84.79%-99.65%.In the phylogenetic tree,52 ChiVMV isolates from different origins were phylogenetically divided into 3 different clusters.The clustering results manifested obvious geographical distribution characteristics.The results of genetic diversity and evolution analysis demonstrate that all of the isolates populations showed high genetic diversity due to the influence of geographical distribution.Significant genetic differentiation and low frequency of gene exchange happened among populations.The results of our study have potential implications for the breeding of ChiVMV resistant varieties and the control of ChiVMV.