Bio-efficacy of insecticides against mustard aphid (Lipaphis erysimi) in Indian mustard (Brassica juncea L.)

Abstract

The study was aimed to evaluate the efficacy of different insecticides in minimizing aphid (Lipaphis erysimi) damage in the Indian mustard (Brassica juncea) under natural infestation of the pest. The field experiment was conducted at the farmer’s field in Rewari, Haryana during 2021-22. The experiment was laid out in randomized block design with seven treatments viz., imidacloprid 17.8 SL @ 125 ml ha-1, thiamethoxam 25 WG @ 100 g ha-1, thiamethoxam 25 WG @ 50 g ha1 , acetamiprid 20 SP @ 50 g ha-1, imidacloprid 17.8 SL @ 100 ml ha-1, fipronil 5 SC @ 1000 ml ha-1 and control and replicated thrice. Insecticides were sprayed as per the treatment at the pod developmental stage of the crop. Results showed that the imidacloprid 17.8 SL @ 125 ml ha-1 was found highly effective (97.7 %) in reducing aphid infestation and increasing seed yield of mustard (1773 kg ha-1) against the control (1346 kg ha-1). The thiamethoxam 25 WG @ 100 g ha-1 was next best treatment with 94.9 % reduction in aphid population and 1731 kg ha-1 of seed yield. The maximum gross returns (Rs. 89537 ha-1), net returns over control (Rs. 20614 ha-1) and incremental benefit: cost ratio (21.7) also obtained under imidacloprid 17.8 SL @ 125 ml ha-1, followed by thiamethoxam 25 WG @ 100 g ha-1. Thus, use of imidacloprid 17.8 SL @ 125 ml ha-1 could be effective and economically viable option for the management of aphid in Indian mustard