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 ۲۷±۲ c and ۶۰±۱۰% R.H with a photoperiod of ۱۲:۱۲ (L:D) h. Contact toxicity of three types of lambda-cyhalothrin formulations: emulsifiable concentrate- EC (ICON ۵ EC), capsule suspension- CS (DEMAND ۱۰ CS) and wettable powder- WP (ICON ۱۰ 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 LC۵۰ values of ۹.۸۷ and ۱۲.۲۴ mg ai. m-۲ against males and females, respectively. The formulation of CS attained LC۵۰ values of ۱۱.۰۲ and ۱۳.۴۲ mg ai. m-۲ and that the formulation of EC attained the values of ۱۲.۳۰ and ۱۵.۰۱ mg ai. m-۲ against males and females, respectively. Conclusion: The results demonstrated that the formulation of WP has high insecticidal activity against German cockroach.