Establishment of baseline toxicity data to different insecticides for Aphis craccivora Koch and Rhopalosiphum maidis (Fitch) (Homoptera: Aphididae) by glass tube residual film technique

Aphis craccivora koch is one of the most important pests of legumes,and rhopalosiphum maidis (fitch),is a serious pest of gramineous crops. susceptible strains of these two species were obtained and the baseline toxicity of 15 commonly used insecticides was established by a standard glass tube residual film method. the results showed that lc50 values of 15 tested insecticides against a. craccivora and r. maidis varied from 0.79 to 52.23 mg/l and 1.03 to 39.20 mg/l,respectively. chlorpyrifos was proved to be the most toxic insecticide against both the species whereas abamectin was least toxic. susceptible toxicity baselines data of both a. craccivora and r. maidis to 15 insecticides established in this study could be used as a reference for resistance monitoring or other related researches. copyright 2013 zoological society of pakistan.