Evaluation of integrated pest management modules against American bollworm, Helicoverpa armigera Hub. in non-Bt cotton

摘要

Field studies were conducted at Regional Agricultural Research Station, Guntur to demonstrate the performance of IPM module against American bollworm, Helicoverpa armigera Hub. in non-Bt cotton during the kharif seasons from 1999-2002.The IPM module comprising summer ploughing, FYM application, leaf hopper tolerant variety (L 604), seed treatment, stem application, intercropping, jowar as border crop, marigold and castor as trap crop, erection of bird perches, pheromone trap monitoring, release of egg parasitoid, Trichagrarnma chitonis, topping of plants, manual picking and destruction of eggs and grown up larvae, spraying of 5 per cent NSKE and need-based spraying of insecticides was tested. Due to the adoption of recommended IPM practices the incidence of American bollworm, Helicoverpa armigera in terms of per cent square damage and per cent green boll damage was low in IPM module when compared to farmers' method. As a result the number of insecticide sprayings was reduced from 18.33 in farmers'method to 5.33 in IPM module which resulted in higher net income and higher incremental cost : benefit ratio of 1 : 4.94 in IPM module compared to 1 : 0.8 in farmers' method.