【摘要】 目的观察四种杀虫剂(奋斗呐、氯菊酯、敌敌畏、马拉硫磷)对灭蚤地区印鼠客蚤的毒性。方法将用丙酮配制的药液100μl加在Φ35mm的滤纸药膜上,20min后放入50ml离心管盖中,接15匹成蚤于离心管(底部有20个Φ0.5mm小孔以通气)中,旋紧盖子并倒置。在温度(25±1)℃,相对湿度(85±5)%的培养箱中接触药膜24h,检查死虫数,计算LC50及95%可信区间范围。结果雷州平步、遂溪洋青、廉江营仔和潮洲饶平(对照点)的印鼠客蚤对奋斗呐、氯菊酯、敌敌畏、马拉硫磷相应的LC50分别为510.51mg/L、923.63mg/L、10.40mg/L、1224.62mg/L;293.22mg/L、349.95mg/L、9.11mg/L、775.00mg/L;255.27mg/L、219.99mg/L、8.27mg/L、559.37mg/L;176.81mg/L、199.66mg/L、5.73mg/L、583.31mg/L。雷州平步、遂溪洋青、廉江营仔各自相应的LC50与潮洲饶平(对照点)的LC50的比值分别为2.89、4.63、1.82、2.10;1.66、1.75、1.59、1.33;1.44、1.10、1.44、0.96。结论除了廉江营仔印鼠客蚤对马拉硫磷毒性敏感外,4种杀虫剂对雷州半岛灭蚤地区的印鼠客蚤的毒性降低,并以雷州平步的情况较为明显。更多还原

【Abstract】 Objective To study the toxicity of Fendona, Permethrin,Dichlorovs and Malathion on Xenopsylla cheopis in the flea-killing areas. Methods Paper filter disk (35 mm diameter) containing 100 μl of insecticide solution was fixed to the lid of a 50 ml centrifugal tube. About 15 adult fleas were transferred to the tube with 20 holes (diameter 0.5 mm) and then covered with the lid immediately.The tubes were kept at the inverted position so that the fleas were allowed to contact the insecticide freely. The fleas were then incubated in an incubator [(25± 1)℃, RH=(80±5)%].The number of survivors was recorded after 24 h of incubation. LC50 and 95% confidence limits were then determined. Results The LC50 of Fendona, Permethrin, Dichlorovs and Malathion was 510.51, 923.63,10.4 and 1224.62 mg / L,respectively in Leizhoupingbu. 293.22,349.95,9.11 and 775.00 mg / L, respectively in Suixiyangqing. 255.27, 219.99, 8.27 and 559.37 mg / L, respectively in Lianjiangyingzai. 176.81, 199.66, 5.73 583.31 mg / L, respectively in Chaozhouraoping (the control area). The Leizhoupingbu,Suixiyangqing,Lianjiangyingzai LC50 of Chaozhouraoping (the control area) was 2.89, 4.63, 1.822.10; 1.66, 1.75, 1.59, 1.33; 1.44, 1.10, 1.44, 0.96, respectively. Conclusion Xenopsylla cheopis in Lianjiangyingzai was sensitive to malathion. The toxicity of all four insecticides to Xenopsylla cheopis in the flea-killing areas,especially in Leizhoupingbu of Leizhou peninsula was low.更多还原