The comparison of contact toxicity of three formulations of lambda-cyhalothrin against German cockroach adults

Introduction: The German cockroach, Blattella germanica (L.), is one of the most serious household insect pests. Current control strategies rely heavily upon application of various formulations of insecticides. The purpose of the present study was to test the short-term effects of formulation of capsule suspension in comparison with formulations of wet table powder and emulsifiable concentrate of lambda-cyhalothrin on German cockroach adults and to choose the most appropriate formulation for practical control measures. Methods: Cockroaches were collected by hand catch and trap, and reared at 27±2 c and 60±10% R.H with a photoperiod of 12:12 (L:D) h. Contact toxicity of three types of lambda-cyhalothrin formulations: emulsifiable concentrate- EC (ICON 5 EC), capsule suspension- CS (DEMAND 10 CS) and wettable powder- WP (ICON 10 WP) were compared against German cockroach adults, Blattella germanica (L.) (Blattaria: Blattellidae). Six concentrations of each formulation were used with ten replicates. Results: The Result showed that the most potent formulation was WP with the LC50 values of 9.87 and 12.24 mg ai. m-2 against males and females, respectively. The formulation of CS attained LC50 values of 11.02 and 13.42 mg ai. m-2 and that the formulation of  EC attained the values of 12.30 and 15.01 mg ai. m-2 against males and females, respectively. Conclusion: The results demonstrated that the formulation of WP has high insecticidal activity against German cockroach.