湖北和广西辣椒脉斑驳病毒的检测及遗传多样性分析

Detection and genetic identity of Pepper veinal mottle virus in Hubei and Guangxi

【目的】研究辣椒脉斑驳病毒(Pepper veinal mottle virus,PVMV)的分布及遗传变异,为明确该病毒在我国的流行扩散分子机制提供理论依据。【方法】利用特异性引物反转录PCR(RT-PCR)检测从湖北宜昌及广西南宁和百色采集的48份疑似感染PVMV的辣椒样本;采用常规Sanger测序测定PCR产物序列,序列采用MEGA 5.0构建系统发育进化树,采用RDP等算法分析其可能的重组事件;采用DnaSP v5分析病毒株系不同群体之间的基因流及基因差异。【结果】从48份辣椒样本中检测到5份样本被PVMV侵染,检出率10.42%。基因同源性比对分析结果表明,测定的PVMV湖北和广西分离物CP基因序列同源性在97.00%以上,与其他地区分离物的同源性为91.73%~98.78%。系统发育分析表明,湖北(YC)和广西(NN)PVMV分离物与我国台湾PVMV分离物的亲缘关系最近。重组分析表明,PVMV广西分离物NN10有2个重组事件。【结论】湖北和广西辣椒的PVMV检测结果表明,该病毒已扩散至湖北和广西;基因突变可能是PVMV湖北分离物遗传变异的主要方式之一;而基因重组和基因突变可能是PVMV广西分离物遗传变异的重要因子。

【Objective】This study aimed to define the distribution and genetic variation of Pepper veinal mottle virus(PVMV),the results would be contributed to understanding the dispersing molecular mechanism of PVMV in China.【Method】PVMV was identified by specific primer reverse transcription PCR(RT-PCR)from 48 suspected pepper samples,which collected from Yichang in Hubei,and Nanning and Baise in Guangxi,and amplified products by PCR were sequenced by Sanger sequencing.The phylogenetic tree was constructed by MEGA 5.0.The recombinant events were analyzed by RDP algorithm.The gene flow and gene differentiation of different populations of PVMV isolates was analyzed by DnaSP v5.【Result】There werefive PVMV positive pepper samples confirmed by RT-PCR among the 48 samples,and the incidence of PVMV in Hubei and Guangxi was 10.42%.According to gene homology detection,the sequences of CP genes of Hubei and Guangxi isolates shared over 97.00%identity with each other,and shared 91.72%-98.78%with isolates from others areas.Phylogenetic analysis showed the relationship of Hubei(YC)and Guangxi(NN)isolates had the closest relation isolates of Taiwan of China.There were two recombinant events detected in PVMV Guangxi isolate NN10.【Conclusion】The survey and detection of PVMV shows that PVMV has infected pepper plants in Hubei and Guangxi.Gene mutation may be one of key patterns for evolution of PVMV Hubei isolates,and gene mutation and recombinant are probably key factors for PVMV guangxi isolates evolution.