Biochemical effects of lambda-cyhalothrin and lufenuron on Culex pipiens L. (Diptera: Culicidae)

The present study aimed to compare between the action of the pyrethroid insecticide lambda-cyhalothrin and the benzoylphenylurea lufenuron on total protein, carbohydrate and lipid content, and on digestive enzymes, transaminases, phosphatases and chitinase activity of Culex pipiens L. late third-instar larvae compared to the control. Both lambda-cyhalothrin and lufenuron significantly reduced total carbohydrate content, and carbohydrases, glutamic oxaloacetic acid transaminase and phosphatases activity. Lambdacyhalothrin significantly decreased total protein content, and protease and glutamic pyruvic acid transaminase activity, whereas it significantly increased chitinase activity. Lufenuron significantly decreased total lipid content, and lipase activity. It can be concluded that lambda-cyhalothrin and lufenuron induced significant metabolic alterations in Cx. pipiens late third-instar larvae by acting on different secondary targets.