Field efficacy of some insecticides against leaf folder of rice

摘要

Beside yellow stem borer, leaf folder Cnaphalocrocis medinalis is another important insect pest in rice.Leaf folder, which was of minor importance, assumed major pest status in the recent years causing extensive damage and considerable yield loss to the crop. The present investigation is aimed at generating information on efficacy of some insecticides against leaf folder of rice. The trial was laid out in randomized block design with three replications in variety Jaya during the dry season, 2013 and2014 in the research farm of National Rice Research Institute, Cuttack. To study the efficacy of nine insecticides, treatments were applied at 45 and 75 days after transplanting along with untreated control. Fipronil 5% SC @ 1000 ml ha ~' was the best insecticide with highest yield of 6.3 and 5.75 t ha~(-1)1 during 2013 and 2014 respectively and was at par with bifenthrin 10% EC @ 500 ml ha~(-1), quinalphos 25% EC @ 1500 ml ha~(-1)1 in increasing the grain yield and reducing leaffolder damage. All the tested insecticides i.e. fipronil 5% SC @ lOOOml/ha, bifenthrin 10% EC @ 500 ml ha~(-1)', quinalphos 25% EC @ 1500 ml ha~(-1), dimethoate 30%EC @ 830 ml ha~(-1), imidacloprid 17.8%SL @ 300ml ha~(-1), lambda cyhalothrin 2.5%EC @500ml/ha, thiamethoxam 25% WG @ 100g ha~(-1),flubendiamide 39.35% SC @ 50 ml ha~ ', acephate 75% SP @ 1000 g ha~(-1) were very effective against leaffolder as compared to control.