(.Effect of Bacillus sphaericus on Different Developmental Stages of Culex pipiens L. and Aedes caspius (P

Abstract

The possibility of using the bacterial mosquito larvicid Bacillus sphaericus in controling the C. pipiens larvae and A. caspius larvae was studied. It is one of the most safe biological agents for human being and animals to decrease the use of chemical insectecides and prevent the environmental polution. The obtained results indicated the following : - The results indicated that the C. pipiens larvae was more susceptable to the bacterial larvicide Bacillus sphaericus than A. caspius larvae. - The dosage levels of this bacteria have great influence in its toxicity, high concentrations evoked a rapid lethal response to the entire tested larvae, while low dosage resulted in significant mortality rates with increasing exposure time and water temperature. Biochemical approaches have been developed to increase the activity of Bacillus sphaericus against the Culex larvae and Aedes larvae.