Status of insecticide resistance in lesser grain borer, Rhyzopertha dominica to Malathion and Deltamethrin in Andhra Pradesh

Abstract

A laboratory experiment was carried out with insecticide resistance levels of malathion and deltamethrin against different populations of lesser grain borer during 2015-16. Rhizopertha dominica populations showed 3.07, 2.61 and 3.80 folds resistant at LC50 level to malathion (from Ghantasala, Maruteru and Bapatla, respectively) in comparison to laboratory susceptible population. The Jangamaheswarapuram and Nalgonda populations of R. dominica showed 2.10 and 1.80 folds resistant (LC50) to malathion, respectively when compared to their laboratory susceptible population. The Bapatla and Maruteru populations were 1.60 and 1.07 folds resistant at LC50 level to deltamethrin, respectively in comparison with laboratory susceptible population at 72 hours after treatment. The Jangamaheswarapuram population recorded 1.04 (LC50) folds resistant to deltamethrin in comparison to laboratory susceptible population. The Ghantasala and Nalgonda populations were recorded resistance as 0.92 folds at LC50 resistance was recorded as 1.01 and 1.21 folds in comparison with the laboratory susceptible population, respectively.