Bio-efficacy of botanical insecticides against rice gall midge (Orseolia oryzae) in Ranchi, Jharkhand

Abstract

A field trial was conducted at Rice Research Farm of Birsa Agricultural University, RAC (Ranchi Agriculture College) Kanke, Ranchi during Kharif season of 2017 on rice variety Bhadshah Bhog to evaluate the bio-efficacy of different botanical insecticides including untreated control against rice gall midge, Orseolia oryzae. Two sprays at tweenty days interval of ten treatments with three replications were applied in the field. The obtained after each spray revealed that the botanical insecticidal treatments were significantly superior over control in reducing silver shoot infested by gall midge and efficacy was maximum in Neem Baan (Aza. 1.0% EC) @ 1000 ml/ha (4.71% SS) with maximum net profit of Rs. 21325 / ha with B:C ratio 8.5: 1. Neem Baan (Aza. 1.0% EC) could be responsible for realization of the highest grains yield (34.03q/ha) among all the tested botanical insecticides in the present studies. However, when all the treatments including the chemical insecticide, chlorpyriphos (@ 2000 ml/ha) are compared in the context of yield of grains, chlorpyriphos took the lead in the highest yield realization (38.95 q//ha) with net profit of Rs. 31950/ ha with B:C ratio7.7: 1.