Bio-efficacy of Mineral Oil against Yellow Mite in Dark Jute (Corchorus olitorius L.) under Terai Region of West Bengal

Abstract

An experiment was conducted during pre-kharif season of 2016 and 2017 to determine the efficacy of relatively cheaper, safer horticultural mineral oil on yellow mite (Polyphagotarsonemus latus). The experiment was laid out in randomized block design with seven treatments [T1- mineral oil @ 3 ml/litre at 35 and 50 days after sowing, T2- mineral oil @ 6 ml/litre at 35 and 50 DAS, T3- mineral oil @ 9 ml/litre at 35 and 50 DAS, T4-Neem oil @ 3 ml/litre at 35 and 50 DAS, T5- mineral oil @ 3 ml/litre + neem oil @ 3 ml/litre at 35 and 50 DAS and T6- Control] replicated four times. Two scheduled spraying of each treatment was done on standing jute crop at 15 days interval. The effect of treatments was significant on post treatment mite population recorded after spray for both the cropping season. Among the treatments, T5 was found to be the most effective combination. The post treatment observation during 2016 and 2017 at 7 days after treatment indicated significantly less number of mites i.e. (1.08 and 0.84 mites cm-2) and (0.83 and 0.41 mites cm-2) respectively in the treatment T5. Within the treatments, maximum plant height (216.92 and 206.64 cm) and yield (34.68 and 28.28 q ha-1) were also observed in treatment T5. Considering the effectiveness against mite on jute as well as the environmental safety, mineral oil might be suggested as biorational component of IPM for effective management of yellow mite.