Relative efficacy of newer insecticides against gram pod, Helicoverpa armigera

Abstract

The experiment was conducted at Students’ Instructional Farm of Narendra Deva University of Agriculture and Technology, Kumarganj, Faizabad during Rabi season 2015-16. Studied on Emamectin benzoate 5 SG @ 11 g a.i./ha was found most effective insecticide (94.44 %) to reduce the larval population, it was followed by flubendiamide 480 SC @ 30 g a.i./ha that gave 87.78 per cent reduction, which was at par with rynaxypyr 20SC @ 40 g a.i./ha (83.33 %). Least effective treatment was Lufenuron 50EC @ 60 g a.i./ha. in which only 64.44 percent reduction in larval population was registered. Reduction in larval population computed from data recorded 14 days after spraying revealed that all the treatments were effective and significantly superior to control. Emamectin benzoate 5 SG @ 11 g a.i.//ha was found most effective that reduced 100.00 per cent larval population. Emamectin benzoate 5 SG @ 11 g a.i.//ha treated plots gave maximum grain yield (18.00 q/ha), it was at par with flubendiamide 480 SC @ 30 a.i./ha and Rynaxypyr 20SC @ 40 g a.i./ha in which 17.00, 16.50 q/ha grain yield, respectively were recorded. Maximum cost- benefit ratio was obtained in plot treated with flubendiamide 480 SC @ 30 g a.i./ha (1:10.06) followed by emamectin benzoate 5 SG @ 11 g a.i.//ha (1:9.20). Lowest cost -benefit ratio (1:3.10) was found in Lufenuron 50 EC@ 60 g a.i./ha treated plot.