入侵江西赣州的草地贪夜蛾的分子鉴定

Molecular identification of invasive Spodoptera frugiperda in Ganzhou,Jiangxi province

【目的】江西省是我国草地贪夜蛾迁飞过渡区和高度适生区,采用分子标记来鉴定江西赣州草地贪夜蛾的种群生物类型,有利于明确入侵江西赣州的草地贪夜蛾的种群生物型并了解其发生及扩散规律。【方法】采用COⅠ和Tpi分子标记方法,对江西赣州32个草地贪夜蛾样本进行扩增、测序和比对分析,明确江西赣州的种群的生物型及遗传特征。【结果】通过DNA提取、PCR扩增及测序,在32份样品中获得了与预期片段大小一致的基因片段,COⅠ基因片段长度为713-779bp,Tpi基因片段长度为383-395 bp。基于线粒体COⅠ基因分析结果表明,玉米型占62.5%,水稻型占37.5%;基于Tpi基因分析结果表明,所有样本均为玉米型,且玉米型中又存在3种类型(Tpi-Ca1型、Tpi-Ca2型及杂合的Tpi-Ca1/Ca2型)。基于COⅠ基因构建的系统进化树,江西赣州的草地贪夜蛾与中国的江苏、云南及江西等、美国的波多黎各和佛罗里达)、非洲的乌干达等的COⅠ序列一致,与巴西的COⅠ序列存在一些差别。【结论】该研究有助于为分析江西赣州的草地贪夜蛾的来源、遗传特性、发生动态等提供更多的信息,积累群体遗传理论数据,提供科学信息。

[Objectives]To clarify the population biotype of invasive Spodoptera frugiperda in Ganzhou,Jiangxi province in order to better understand the occurrence and spread of this important,global agricultural pest.[Methods]Molecular identification of 32 S.frugiperda specimens collected in Ganzhou,Jiangxi province was based on variation in the COⅠand Tpi molecular markers.DNA was extracted from each specimen,amplified with PCR and sequenced using COⅠand Tpi molecular markers,after which the COⅠand Tpi gene fragment sequences obtained were analyzed.[Results]Gene fragments of the expected fragment size were obtained from all 32 samples.The length of the COⅠgene fragment was 713-779 bp,and that of Tpi gene fragment was 383-395 bp.Based on previous analysis of the CO I gene,the corn strain of S.frugiperda accounted for 62.5%of specimens and the rice strain for 37.5%.However,on the basis of Tpi gene variation,all specimens were of the corn-strain,of which there were three types(Tpi-Ca1,Tpi-Ca2 and hybrid Tpi-Ca1/Ca2).A phylogenetic tree of COⅠgene variation indicates that S.frugiperda COⅠsequences in Ganzhou,Jiangxi province are consistent with those elsewhere in China(Jiangsu,Yunnan and Jiangxi),in the United States(Puerto Rico and Florida),in Africa(Uganda),but differ from those in Brazil.[Conclusion]This study clarifies the genetics of S.frugiperda in Ganzhou,Jiangxi province,thereby increasing the available information on the population genetics of this important global pest.