中国尖音库蚊复合组蚊虫的抗性动态和遗传多样性研究

Studies on the Resistance Dynamic and Genetic Diversity of Culex pipiens Complex from Four Different Geographical Locations

本文通过采用生物测定、蛋白质电泳和等位酶分析等方法对4个地理种群尖音库蚊复合组蚊虫（Culex pipiens complex）的抗性水平、群体中酯酶基因表型分布和种群遗传多样性进行了研究。抗性检测结果表明，4个库蚊种群对敌敌畏、对硫磷、氯菊酯和溴氰菊酯的抗性较高，对残杀威、巴沙和胺菊酯的抗性较低，4个种群抗性大小是：山东淄川〉湖北沙市〉广东茂名〉北京沙河，淄川种群蚊虫对敌敌畏抗性为66．7倍。酯酶电泳结果中，沙市和茂名2个库蚊种群酯酶表型多态性最高，淄川库蚊种群多态性最低，过量表达的B1比率占100％。种群遗传多样性研究表明，每位点平均等位基因数（A）为1．92，平均多态位点百分率（P）为52．78％，平均预期杂合度（胁）为0．130，群体间遗传分化系数（Fst）值为0．368，平均基因流Nm=1．52，说明4个种群有较丰富的遗传多样性，群体之间存在相当多的遗传多样性，种群间的基因交流较低，遗传分化较大，表明与地理位置存在一定对应关系。

With the methods of bioassay, protein electrophoresis, and the analysis of resistant alleles, we chose 4 Culex pipiens complex populations from Shahe （Beijing）, Zichan （ Shandong Province）, Shashi （ Hubei Province） and Maoming （ Guangdong Province）, to study their resistance levels to various insecticides, esterases genotype distribution and genetic diversity. Their resistance levels to 7 insecticides are shown as follows： All Cx. pipiens populations have higher resistance to dichlorovos, parathion, dehamethrin and permethrin than to propoxur, hassa and tetramethrin. The resistance of the population from Zichuan was the highest, followed by Shashi, Maoming, and Shahe. The population from Zichuan was 67-fold higher resistance for dichlorovos than sensitive Culex lines. The esterases of the Culex populations from Maoming and Shashi exhibited the highest phenotype polymorphism, but the lowest polymorphism was observed in the population from Zichuan, and 100% of overexpressed B1 was detected, as shown by starch electrophoresis. Population genetics shows that the number of average alleles, average polymorphism site average expected hcterozygosity, differentiation coefficient and average gene flow are 1.92, 52.78 % , 0.13, 0. 368 and 1.52, which indicated that the 4 populations is genetic diversity, that there were a large number of genetic diversities among the 4 populations, that less gene communication occurred among the populations, matched well with the geographical locations.