洗涤灵杀灭白纹伊蚊蛹的效果观察

Efficacy of detergent against the pupas of Aedes albopictus

目的研究日用洗涤灵对白纹伊蚊蛹杀灭效果。方法试验设洗涤灵0.05、0.1、0.2、0.5、1.0m l/L 5个浓度组和一个脱氯自来水对照组。每个浓度加试验液200 m l,放30只蛹。观察试验当天(T+0 d)、24 h(T+1 d)、48 h(T+2 d)、72 h(T+3 d)蛹死亡数、活蛹数、成功羽化数和羽化后成蚊淹死数。每组均做2次平行试验。比较不同浓度组蛹死亡率、蛹平均死亡时间、羽化率、平均羽化时间、成蚊淹死率差异,用B liss法计算洗涤灵致蛹死亡的LD50。结果洗涤灵高浓度组蛹死亡率明显高于低浓度组和对照组(χ2=252.8,P=0);洗涤灵致蛹死亡的LD50为0.1 m l/L。洗涤灵高浓度组蛹平均死亡时间低于低浓度组和对照组(χ2=92.3,P=0);洗涤灵高浓度组羽化率明显低于低浓度组和对照组(χ2=255.4,P=0);不同浓度的洗涤灵对蛹的平均羽化时间没有影响(χ2=0.478,P=0.784);洗涤灵浓度达到0.1 m l/L时,成蚊淹死率已达100%。0.05 m l/L浓度组成蚊淹死率明显高于对照组(χ2=49.3,P=0)。结论洗涤灵较低浓度能对白纹伊蚊蛹起到很好的防治效果,其机理可能与洗涤灵降低水的表面张力后干扰蛹呼吸和阻止羽化后成蚊飞离水面有关。

Objective To explore the effect of detergent against pupa of Aedes albopictus. Methods Five groups of dishwashing detergent with dosages of 0. 05,0. 1,0. 2, 0. 5, 1.0 ml/L and one tap-water eontrol group were set up. Thirty pupas of Aedes albopictus were added by a straw to a plastic bowl full of 200 ml testing solution. The number of dead pupas, survival pupas, drown-mosquitoes and successful eclosion mosquitoes were counted in the day （T＋0d）, and thedav after 24 h （T＋1 d）, 48 h （T＋2 d）, 72 h （T＋3 d）. Two parallel tests were carried out in each group at the same time. The mortality of pupa, the average of pupa death time, the ratio of eclosion, the average eclosion time and the ratio of drown-mosquito of between groups were analyzed. LD50 of pupa death was calculated by the method of Bliss. Results Pupa mortality of the high concentration group of the dishwashing detergent was signifieantl）higher than the low concentration groups and the control group（ x^2 = 252.8, P = 0）. LD50 of pupa death was 0. 1 ml/L. Compared with the low concentration groups and the control group, the average pupa death time of the high concentration group was shorter. The ratio of eelosion mosquito of the high concentration group and the control group was statistically lower than the low concentration group and the control group （x^2 = 255.4 ,P=0）. Different dosage of the dishwashing detergent didn＇t affect the average time of pupa eclosion （x^2 = 0. 478,P = 0. 784）. At the dosage of 0. 1 ml/L, the rate of drown-mosquito reached 100%. At the dosage of 0. 05 ml/L, the rate of drown-mosquito was significantly higher than control group（x^2 = 49. 3, P = 0 ）. Conclusion Even at low dosage, the detergent can effectively kill the pupas of Aedes albopictus, whose mechanism is concerned with that the detergent interferes pupas＇ breath and prevents mosquitoes flying off the water by cutting down the water＇s surface tension.