Evaluation of Some Novel Insecticides Against Yellow ·stem Borer, Scbpopllaga Incertulas (Walker) and Leaf Folder, Cnaphalocrocis Jnedinalis (Guenee) and Their Effect on Natural Ene1nies in Basmati Rice

Abstract

An investigation was carried out to study the "Evaluation of some novel insecticides against yellow stem borer, Scirpophaga incertulas (Walker) and leaf folder, Cnaphalocrocis medina/is (Guenee) and their effect on natural enemies in basmati rice" in randomized block design with three replications at Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut during Kharif2012. During the crop season, thirteen insect species were found attacking the basmati rice at different crop growth stages. Among them, rice stem borer, Scirpophaga incertulas (Walker) and rice leaf folder, Cnaphalocrocis medina/is (Guenee) were recorded as major pests. The gundi bug, Leptocorisa acuta (Thumb) was found moderately damaging the crop. Efficacy of different insecticides viz., fipronil 0.3% GR, lambda cyhalothrin 5 EC, chlorantraniliprole 18.5 SC, indoxacarb 14.5 SC, chlorantraniliprole 0.4% GR, cartap hydrochloride 4 G, chlorpyriphos 20 EC and cypermethrin 25 EC tested against S. incertulas and C. medinalis revealed that chlorantraniliprole 18.5 SC @ 150 mllha and chlorantraniliprole 0.4% GR @ 10 kg/ha was found most effective treatment in reducing the population of both pests followed by fipronil 0.3% GR @ 20 kglha. The chlorpyriphos 20 EC and cypermethrin 25 EC @ 1 lit/ha was recorded less effective. Chlorantraniliprole 18.5 SC and chlorantraniliprole 0.4% GR was found most safer to natural enemies population (spiders and coccinellids) followed by fipronil 0.3% GR, the treatments chlorpyriphos 20 EC and cypermethrin 25 EC proved more toxic to natural enemies population (spiders and coccinelids) at all observational interval. The higher yield was obtained from chlorantraniliprole 18.5 SC whereas, highest cost benefit ratio is obtained from chlorantraniliprole 0.4% GR.