Detection of insecticidal resistance against various insect pests in vegetable crops at Raipur

Abstract

Bioassay methods such as leaf dip and larvae dip were used in the laboratory conditions for testing lethal dose of insect pests conducted at laboratory of department of entomology, IGKV, Raipur (C.G.) during 2009-2010. At least five dilutions for each of the selected insecticides were tested using different methods. In each method and insecticide at least 10 larvae of 2-3 rd instars were released on each dilution in 3 replications along with untreated control. The results shown that the Helicoverpa armigera population was maximum LD 50 value to Chlorpyriphos (O.633 μg/lit) followed by Spodoptera litura population LD 50 (0.576 μg/lit) and lower value for Leucinodes arbonalis LD 50 (0.503 μg/lit) and the Plutella xylostella population showed maximum LD 50 value to Cypermethrin (0.810μg/lit) and lower LD 50 value (0.246 μg/lit) for Trichoplusia ni. Therefore, H. armigera showed higher resistance to Chlorpyriphos and P. xylostella showed higher resistance towards Cypermethrin.