基于线粒体ND5基因的我国三省三带喙库蚊种群分化研究

THE POPULATION DIFFERENTIATION OF CULEX TRITAENIORHYNCHUS IN THREE PROVINCES OF CHINA BASED ON MITOCHONDRIAL ND5 GENE

三带喙库蚊是乙型脑炎病毒等多种虫媒病毒的重要传播媒介,我国江苏、浙江和海南省普遍种植水稻,为三带喙库蚊孳生的适宜环境。为了调查三带喙库蚊在这三省的种群分化状态,本研究拟以线粒体ND5基因作为遗传标记对各区域三带喙库蚊种群的遗传多样性和结构进行探讨。结果显示,各区域三带喙库蚊的遗传多样性较高,单倍型多样性指数(Hd)为0.533~0.981,且浙江省三带喙库蚊单倍型多样性指数(0.944)要略高于海南省(0.931)和江苏省(0.910)。各三带喙库蚊种群以单倍型H1、H2和H3为主,而单倍型H9和H12仅分布于海南海口(HNHK)、单倍型H15和H18仅分布于浙江金华(ZJJH)、单倍型H20、H21和H22仅分布于江苏连云港(JSLG)以及单倍型H24和H25仅分布于江苏盐城。UPGMA聚类结果表明该区域三带喙库蚊种群共演化出两个聚类分支,且海南海口株(HNHK)与江苏连云港株(JSLG)、江苏淮安株(JSHA)以及江苏盐城株(JSSY)之间的基因流较强,分别达到13.927、17.423和10.976;江苏连云港株(JSLG)与浙江台州株(ZJTZ)之的基因流达到11.222。AMOVA分析结果显示该区域三带喙库蚊种群分化的主要分子变异来于区域内的各种群之间,所占变异百分比为95.93%;同时,中性检测结果表明三带喙库蚊种群未出现明显的种群扩张。

Culex tritaeniorhynchus is an important vector of various viruses,such as Japanese encephalitis,and rice cultivation is very common in Jiangsu,Zhejiang,and Hainan provinces in China,providing an ideal environment for the breeding of Cx.tritaeniorhynchus.To investigate the genetic differentiation status of Cx.tritaeniorhynchus populations among these regions of China,the mitochondrial ND5 gene was used as a genetic marker to explore the genetic diversity and population structure of Cx.tritaeniorhynchus in this region.The results showed that the genetic diversity of Cx.tritaeniorhynchus in this region was relatively high,with a haplotype diversity index(Hd)ranging from 0.533 to 0.981,Moreover,the Hd index of Cx.tritaeniorhynchus population in Zhejiang province(0.944)is slightly higher than that in Hainan(0.931)and Jiangsu province(0.910).H1,H2,and H3 are the major haplotypes of each population,while H9 and H12 are only distributed in Haikou population(HNHK),H15 and H18 are only distributed in Jinhua population(ZJJH),H20,H21,and H22 are only distributed in Lianyungang population(JSLG),and H24 and H25 are only distributed in Yancheng population.The UPGMA clustering results indicate that the Cx.tritaeniorhynchus populations in this region have evolved into two clustering branches,and the gene flow between the Hainan Haikou strain(HNHK)and Jiangsu Lianyungang strain(JSLG),Jiangsu Huai'an strain(JSHA),and Jiangsu Yancheng strain(JSSY)are strong,reaching 13.927,17.423,and 10.976,respectively;the gene flow between Jiangsu Lianyungang strain(JSLG)and Zhejiang Taizhou strain(ZJTZ)reached 11.222.Meanwhile,the AMOVA analysis results showed that the main molecular variations of the Cx.tritaeniorhynchus populations derived from various groups within the region,accounting for 95.93%of the variation percentage,meanwhile,no obvious population expansion was observed among the populations of this region.