Residue behavior of combination formulations of insecticides in/on cabbage and their efficacy against aphids and diamondback moth.

Persistence behavior of insecticides chlorpyriphos, profenofos, triazophos, cypermethrin, and deltamethrin following the use of three combination formulations Action 505 (chlorpyriphos + cypermethrin), Roket 44EC (profenofos + cypermethrin), and Anaconda Plus (triazophos + deltamethrin) was studied in cabbage following the spray application at the recommended and double doses. Bio-efficacy of these formulations was also evaluated against mustard aphids (Lipaphis erysimi Kaltenbach) and diamondback moth (Plutella xylostella L.). The residues of different insecticides persisted for 5-8 days at low dose and 8-12 days at high dose. The residues dissipated with time and 87-100% dissipation was recorded on the 8th day. The half-life values varied from 0.4 to 1.6 days. Based on the acceptable daily intake (ADI) values, a safe waiting period of 1 day has been suggested for the formulations Action 505 and Roket 44EC and 3 days for Anaconda Plus at the recommended dose of application. Action (1.6 L/ha) treatment was found to be the best as it significantly reduced the diamondback moth (DBM) (~60%) and aphid population (~70%) besides giving the highest yield (170% increase over control).