Field Demonstration of Indigenous Strains Bacillus thuringiensis and Beauveria bassiana for Sustainable Management of Spodoptera litura in Groundnut
M. Pradeep
*
Department of Plant Pathology, S.V. Agricultural College, Tirupati, Acharya N.G. Ranga Agricultural University, Lam, Guntur, India.
G. Narayana Swamy
Department of Horticulture, SMGR Agriculture College, Udayagiri, Acharya N.G. Ranga Agricultural University, Lam, Guntur, India.
P. Pedda Nagi Reddy
Department of Horticulture, S.V. Agricultural College, Tirupati, Acharya N.G. Ranga Agricultural University, Lam, Guntur, India.
G.L. Siva Jyothi
Krishi Vigyan Kendra, Nellore, Acharya N.G. Ranga Agricultural University, Lam, Guntur, India.
*Author to whom correspondence should be addressed.
Abstract
This study by Krishi Vigyan Kendra, Nellore, evaluates the efficacy of biopesticides Bacillus thuringiensis (Bt) and Beauveria bassiana formulations against S. litura compared to conventional insecticides over two growing seasons (2018-19 and 2019-20). Twenty Front Line Demonstrations (FLDs) involving 20 farmers were conducted, with treatments applied when leaf damage exceeded 25%. Results indicated significant reductions in leaf damage (8.40% for biopesticides vs. 8.89% for insecticides) and larval populations. Specifically, larval counts decreased substantially after treatment, with average counts at 50 DAS dropping from 21.29 (FP) to 3.37 (Demo) in 2018-19 and from 22.15 (FP) to 3.53 (Demo) in 2019-20. Economic analysis revealed comparable net returns and benefit-cost ratios for both treatments (1.92 and 1.93 for biopesticides and insecticides, respectively). These findings support the economic viability of adopting biopesticide, promoting sustainable agricultural practices and profitability in groundnut cultivation.
Keywords: Bacillus thuringiensis, Beauveria bassiana, Spodoptera litura, ground nut