Evaluation of thiamethoxam 25 per cent WG against major insect pests of rice (Oryza sativa L.)

An experiment was conducted at Regional Agriculture Research Station, College of Agriculture, Waraseoni, Bagalaght, Madhya Pradesh during the 2014-15 to study on the evaluation of Thiamethoxam 25 per cent WG for the management of stem borer (Scirpophaga incertulas Walker), leaf folder (Cnaphalocrocis medinalis Guenee), gall midge (Orseolia oryzae Wood Mason), leaf hoppers viz., green leaf hopper (Nephotettix virescens Distant), brown plant hopper (Nilaparvata lugens Stal), in rice crop. Thiamethoxam 25 per cent WG used in the experiment was different doses i.e. @ 20 g a.i. /ha, 25 g a.i. /ha, 30 g a.i. /ha, 50 g a.i. /ha, and 100 g a.i. /ha, with insecticidal check Imidacloprid 17.8 SL @ 30 ml a.i./ha. Two sprays of insecticides were applied at fifteen days interval. The most effective dose of thiomethoxam 25 per cent WG in controlling the rice insect pests was 50 g. a.i./ha followed by 30 g a.i. /ha and 25 g a.i. /ha. Per cent reduction of insect pests over untreated plot after final sprays was followed this order of efficacy: Thiamethoxam 25 per cent WG @ 20 g a.i. /ha> 100 g a.i. /ha, > Imidacloprid 17.8 SL @ 30 ml a.i./ha.. Highest cost benefit ratio (1:21.69) was observed in thiamethoxam 50 per cent WG @ 20 g a.i. /ha.