Seasonal Incidence of Insect Pests on Cowpea and Efficacy of Biopesticides against Spotted Pod Borer (Maruca vitrata)

Abstract

A field experiment was conducted during the Kharif season of 2024 at the Organic Research Farm, Bundelkhand University, Jhansi, to study the seasonal incidence of insect pests on cowpea (Vigna unguiculata) and evaluate the efficacy of various biopesticides against the spotted pod borer Maruca vitrata. The experiment followed a randomized block design with nine treatments and three replications, two sprays including Neem oil, Bacillus thuringiensis, Beauveria bassiana, Metarhizium anisopliae, NSKE, and others. Observations revealed that aphids, jassids, whiteflies, thrips, and M. vitrata were the major pests affecting cowpea, with M. vitrata showing peak activity during mid-October. Neem oil proved to be the most effective biopesticide, achieving a 78.8% reduction in pod damage after the second spray, followed closely by B. bassiana and B. thuringiensis. The incidence of M. vitrata was significantly influenced by environmental factors, especially evening relative humidity. These findings emphasize the potential of eco-friendly biopesticides in managing insect pests and reducing reliance on synthetic chemicals in organic cowpea production.