Persistence and Efficacy of Insecticides against Pest Complex of Pea Crop

The initial deposits of 16.74,7.71 and 15.33 ppm for chlorpyrifos, cypermethrin and endosulfan on foliage resulted in 16.6, 3.1 and 11.4% reducation respectively in infestation of leaf miner Phytomyza horticola. The residues of these insecticides were effective but did not show wuch difference in both the species of aphids, Aphis craccivora and Macrosiphum pisum. Chlorpyrifos showed 81% reduction in pod borer damage over control due to high persistence till harvest (0.04 ppm on pod covers). Endosulfan, though persisted in grains till harvest, was not very effective in reducing pod damage below 66 per cent. Maximum avoidable loss of about 47% was obtained with 3 sprays of chlorpyrifos and endosulfan but benefit cost ratio was less in comparison to two sprays at 30 and 60 d after sowing.