Comparative Efficacy of Different Biopesticides against the Tobacco Caterpillar [Spodoptera litura (Fabricius)]

Abstract

Tobacco caterpillar, Spodoptera litura (Fabricius) is an economically important polyphagous pestinflicting significant economic damage to numerous field and horticultural crops. Overreliance of chemical insecticides to manage the pest has led to the development of resistance, resurgence and residue problem in the crop ecosystems, in addition to high operating costs. Biopesticides have been reported to be effective for managing this pest in ecofriendly manner. Hence, the present study was conducted to assess the efficacy of different bio pesticides against S. litura under laboratory conditions at Bihar Agricultural College, Sabour, Bhagalpur during the rabi of 2022-23. It was conducted in completely randomized design (CRD) with eight treatments and three replications.  Among the various biopesticides evaluated, Steinernema carpocapsae- 500 IJs/Petri Plate and Metarhizium anisopliae 1×108 spores/ml -5g/l were most effective treatments and at par each other with 93.00 and 82.50 per cent larval mortality, respectively. They had performed equally with chemical check, Emmamectin benzoate 5 SG- 0.4 g/l which recorded with 95.63 % larval mortality. Neem oil 1500 ppm- 5 ml/litre and Beauveria bassiana 1×108 @5ml/l were the next best treatments with 78.31 and 59.38 % larval mortality respectively. The order of efficiency was Emamectin benzoate 5 SG (0.4g/l) > EPNs (500 IJs) >Metarhizium anisopliae 1% WP (5g/l) >Neem oil 1500 ppm (5 ml/litre) >Beauveria bassiana1 % WP (5 g/l) >Metarhizium anisopliae 1 % WP (2.5 g/l) >Beauveria bassiana 1 % WP (2.5 g/l).