5%吡丙醚·倍硫磷颗粒剂对居民小区雨水井幼蚊控制效果研究

A study of effectiveness of 5% pyriproxyfen and fenthion granules in controlling mosquito larvae in rainwater wells in residential areas

目的研究蚊虫密度高峰期居民小区雨水井积水、幼蚊孳生情况及5%吡丙醚·倍硫磷颗粒剂控制效果,为居民小区雨水井幼蚊控制提供依据。方法 2019年8-9月选择上海市青浦区1处居民小区,小区南部的64个和北部的58个雨水井分别作为实验组和对照组。实验组投入5%吡丙醚·倍硫磷颗粒剂,分别于投药前、投药后1、3、7、14、21和28 d,共计7次调查雨水井积水情况及其幼蚊孳生情况。结果该居民小区122个雨水井连续7次调查,积水次数7次的雨水井共有35个,占28.69%,积水次数1~6次的有12个,占9.83%,7次均无积水的有75个,占61.48%;雨水井积水率维持在30.33%~36.89%(χ^(2)=1.176,P=0.278),积水率与调查前3 d降水量无相关性(r=0.558,P=0.193)。实验组在药物控制后第1天,雨水井幼蚊孳生阳性率下降至16.67%,与控制前62.50%相比,差异有统计学意义(χ^(2)=4.689,P=0.027);同期对照组的幼蚊孳生阳性率维持在41.18%~55.56%,差异无统计学意义(χ^(2)=0.252,P=0.769)。在药物控制后,实验组雨水井14 d后幼蚊阳性率为0;21和28 d后分别为23.81%和38.46%,与对照组差别均无统计学意义(均P>0.05)。结论 8-9月该居民小区雨水井积水情况相对稳定,5%吡丙醚·倍硫磷颗粒剂雨水井蚊虫控制时间约为2周,可对长期积水雨水井定期投药,科学防控雨水井幼蚊孳生。

Objective To investigate water accumulation and mosquito larvae breeding in rainwater wells in residential areas at mosquito density peaks as well as the effectiveness of 5% pyriproxyfen and fenthion granules in controlling the mosquitoes, and to provide a basis for the control of mosquito larvae in rainwater wells in the residential areas.Methods From August to September, 2019, 64 rainwater wells in the south and 58 rainwater wells in the north of a residential area in Qingpu, Shanghai, China were selected as experimental group and control group, respectively. The experimental group was given 5% pyriproxyfen and fenthion granules;water accumulation and mosquito larvae breeding in the rainwater wells were investigated before insecticide application and 1, 3, 7, 14, 21, and 28 days after insecticide application(7 investigations in total). Results Thirty-five(28.69%) rainwater wells had water accumulation during all the 7 consecutive investigations of 122 rainwater wells in the residential area, 12(9.83%) rainwater wells had water accumulation during 1-6 of the 7 investigations, and 75(61.48%) rainwater wells had no water accumulation during all the 7 investigations;the water accumulation rate of the rainwater wells were 30.33%-36.89%(χ^(2)=1.176, P=0.278), and there was no significant correlation between water accumulation rate and precipitation 3 days before investigation(r=0.558, P=0.193). The positive rate of mosquito larvae breeding in the rainwater wells in the experimental group decreased to 16.67% 1 day after insecticide application, showing a significant difference compared to the positive rate(62.50%) before insecticide application(χ^(2)=4.689, P=0.027);the concurrent positive rate of mosquito larvae breeding in the control group was 41.18%-55.56%, showing no significant difference(χ^(2)=0.252, P=0.769);the positive rate of mosquito larvae breeding in the rainwater wells in the experimental group was 0 14 days after insecticide application;23.81% 21 days and 38.46% 28 days after insecticide application, there were no significant difference compared to the control groups(all P>0.05). Conclusion From August to September, the water accumulation in the rainwater wells in the residential area in Qingpu is stable;5% pyriproxyfen and fenthion granules can control the mosquitoes in the rainwater wells for about 2 weeks;therefore, it is recommended to regularly apply insecticides in long-term water accumulation to scientifically control mosquito larvae breeding in the rainwater wells.