Mohammad Djaefar Moemenbellah-Fard; Mohammad Reza Fakoorziba; Kourosh Azizi; Mohsen Mohebbi-Nodezh
Volume 1, Issue 1 , July 2013, , Pages 41-47
Abstract
Background: The German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae), has become resistant to many insecticides due to control failures in hospital and student dormitory settings of southern Iran. Objective: This study was thus designed to detect and monitor carbamate resistance in two ...
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Background: The German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae), has become resistant to many insecticides due to control failures in hospital and student dormitory settings of southern Iran. Objective: This study was thus designed to detect and monitor carbamate resistance in two strains of German cockroach using lethal dose bioassay methods. Methods: Wild dormitory (D) and hospital (H) strains were collected. Adult males were subjected to the jar exposure procedure. A range of concentrations based on the world health organization (WHO) standard concentration of carbamate insecticides (carbaryl, bendiocarb, propoxur) were used. For each insecticide, four to seven different concentrations leading to >0% and propoxur > bendiocarb. The ratio of LD50 in H strain to that of D strain for bendiocarb was about twice that of the other two insecticides indicating that German cockroaches were most susceptible to bendiocarb under both environments. Conclusion: It is concluded that excessive reliance on carbaryl in both D and H settings has led to resistance.