沈阳市淡色库蚊密度监测及其对杀虫剂的抗性调查

Investigation on the density and insecticide resistance of Culex pipiens pallens in Shenyang

目的掌握沈阳市淡色库蚊密度变化和季节消长情况,通过淡色库蚊成蚊对常用杀虫剂的抗性监测,了解其对常用杀虫剂的抗药性水平。方法密度监测采用诱蚊灯法,淡色库蚊成蚊抗药性采用接触筒法进行监测。结果淡色库蚊2018年全年平均密度为4.47只/(台·h),主要集中在城区居民区、公园和医院环境,全年的密度高峰出现在7月上旬,密度为8.7只/(台·h),全年季节密度变化呈现单峰曲线。在不同孳生环境中,医院的平均密度最高,为6.54只/(台·h);牲畜圈平均密度最低,为0.25只/(台·h)。沈阳市城区淡色库蚊成蚊接触溴氰菊酯(2.55μg/cm^2)、高效氯氰菊酯(2.55μg/cm^2)、氯菊酯(25.48μg/cm^2)、残杀威(509.55μg/cm^2)、双硫磷(509.55μg/cm^2)药纸24 h后死亡率分别为6.67%、2.2%、10.09%、30.21%、98.96%。根据抗性水平判断标准,对双硫磷为敏感,对高效氯氰菊酯、溴氰菊酯、氯菊酯、残杀威均产生了一定抗性。结论目前沈阳市城区还是以淡色库蚊为主,密度出现的季节高峰相比2008年有所提前,这与沈阳市的气候变化有一定关系。沈阳市城区内不同生境的淡色库蚊密度与2010年相比都呈现下降趋势。双硫磷可作为沈阳市城市控制蚊虫的药剂。

Objective To understand the density and seasonal fluctuation of Culex pipiens pallens in Shenyang,and to learn the level of resistance to common used insecticides.Methods The density of Culex pipiens pallens was monitored with light trapping method,and the insecticide resistance of Culex pipiens pallens adults was monitored with contact method.Results The annual average density of Culex pipiens pallens was 4.47 mosquitoes/(lamp·h),mainly concentrated in urban residential areas,parks and hospitals.The annual density peak was 8.7 mosquitoes/(lamp·h)in the first half of July,and the annual seasonal density presented a single-peak curve.In different environment,the density in the hospital was the highest as much as 6.54 mosquitoes/(lamp·h),and the minimum in livestock was as much as 0.25 mosquitoes/(lamp·h).The 24 h mortality rates of Culex pipiens pallens exposed to beta cypermethrin(2.55μg/cm^2),decamethrin(2.55μg/cm^2),permethrin(25.48μg/cm^2),propoxur(509.55μg/cm^2),temephos(509.55μg/cm^2)were respectively 6.67%,2.2%,10.09%,30.21%and 98.96%,showing that the Culex pipiens pallens was sensitive to temephos,resistant to beta cypermethrin,decamethrin,permethrin and propoxur.Conclusion Culex pipiens pallens was the dominant species in the urban area of Shenyang,and the seasonal peak of density appeared earlier than that in 2008,which might be related to the climate change in Shenyang.Compared with 2010,the density of Culex pipiens pallens in different habitats in Shenyang City showed a declining trend.Temephos is proposed to be applied in the control of mosquitoes in Shenyang City.