The Control Effect Of Several Insecticides On Culex Pipiens Pallens

Bacillus thuringiensis is a source of microbial pesticides,the prevention and control of mosquito-borne effect is good,because its effect is remarkable,it is not easy to mosquito larvae culling interact resistance,no pollution and is widely used to the environment.This research mainly discusses the bacillus thuringiensis suspending agent of light were culex young mosquito killing effect,and bacillus thuringiensis suspending agent and An Bei double sulfur phosphorus granules,pyrazole propyl ether granules three reagents to light the indoor and outdoor efficacy of the cub culex mosquitoes contrast research,at the same time,also investigated three easy to breed mosquitoes in the aquatic environment,the mosquito young kinds of situation.All experiments was operated with impregnate method recommended by WHO,namely with the increase of age,pale young mosquito culex of bacillus thuringiensis suspending agent of tolerance to the increased sensitivity to decrease.By bacillus thuringiensis suspending agent and An Bei double sulfur phosphorus granules,pyrazole propyl ether granules three reagents to light culex mosquito indoor and outdoor efficacy of contrast test,we found that:Laboratory test conditions: bacillus thuringiensis suspending agent compared with other two kinds of insecticides,the light of culex lethal concentration in the lowest,while its lethal effect on around enough to rival with chemical pesticides An Bei double sulfur,phosphorus,all can reach 100%.As a juvenile hormone inhibitors class pyrazole propyl ether,due to its mainly inhibit the growth and development of the baby mosquitoes so its concentration is higher in death,the mortality is the lowest of three insecticides.Outdoor artificial test conditions: our results showed that An Bei double sulfur is the best insecticides,which the survival rate of mosquitos is only 6% after 4d.Compared with An Bei double sulfur,the efficiency of bacillus thuringiensis suspending is lower,which the the survival rate of mosquitos is 35% after 4d.The efficiency of juvenile hormone inhibitors class pyrazole propyl ether is the lowest,the survival rate of mosquitos is 76%.According to our results,the efficiency of bacillus thuringiensis suspending agent is obviously better than wettable powder of bacillus thuringiensis.We also compared the efficiency of three different insecticides: the LC(50)of bacillus thuringiensis suspending agent is the lowest of three insecticides.But the outdoor experiments results is differ to laboratory results.Although the efficiency of An Bei double sulfur is better than bacillus thuringiensis suspending agent,the mortality of bacillus thuringiensis suspending agent also can reach 65%.We think that the water circumstance may affect the activity of BT.