Studies on Bioefficacy of Novel Insecticides Against Maruca Vitrata (Geyer) and Helicoverpa Armigera (Hubner) in Pigeonpea.

Abstract

The investigation had been carried out at Crop Research Centre (CRC), Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut (U.P) during Kharif, 2020-21.The larval population of Maruca vitrata and Helicoverpa armigera was recorded one day before spray and three and nine days after first and second spray. The larval population of Maruca vitrata was recorded lowest in the plot treated with spinosad 45% SC @ 250 ml/ha is (1.20 larvae/10 plants) and pod damage percentage is minimum (12.55%) followed by indoxacarb 15.5% SC @ 500 ml/ha and Chlorantraniliprole 18.50% SC @ 150 ml/ha. The larval population of pod borer (Helicoverpa armigera Hub.) was recorded lowest in the plot treated with spinosad 45% SC @ 250 ml/ha is (1.67 larvae/10 plants) and pod damage percentage was minimum (9.50%) followed by indoxacarb 15.5% SC @ 500 ml/ha and chlorantraniliprole 18.50% SC @ 150 ml/ha. The spinosad 45% SC @ 250 ml/ha treated plots which gave highest plot yields mean 14.10 q/ha and maximum reduction of population. The next best insecticide in 1st & 2nd spray is indoxacarb 15.5% SC followed by Chlorantraniliprole 18.50% SC and all other treatments. All treatments were superior to untreated control. The effect of various insecticides on natural enemies population (C. septumpunctata and spider) showed that the chlorantraniliprole 18.50% SC @ 150 ml/ha was found highly safe with maximum number of C. septumpunctata (1.00 per plant) and spiders (0.42 per plant) population after second spray, respectively and followed by indoxacarb 15.5% SC @ 500 ml/ha, spinosad 45% SC @ 250 ml/ha, acephate 75% SP @700 g/ha. Novaluron 10% EC @ 250 ml/ha was proved more toxic followed by emamectin benzoate 5% SG @ 250 g/ha against natural enemies population. The highest C:B ratio (1:10.12) was calculated with emamectin Benzoate 5% SG @ 250 g/ha and lowest C:B ratio (1:3.36) was occurred with chlorantraniliprole 18.50% SC @ 150 ml/ha.