Potency and Repellence Effects of Jatropha curcas L. Extracts With and Without Pirimiphos-methyl against Callosobruchussubinnotatus (Pic.) in Stored Bambara Groundnut, Vigna subterranea (L.) Verdcourt

Abstract

The study evaluated the potency and repellence effects of Jatropha curcasL. leaf and seed powders and their combinations with and without reduced rate of Pirimiphosmethyl, on Callosobruchussubinnotatus (Pic.) a major pest of Bambara groundnut, Vigna subterranea (L.) Verdcourt. Factorial experiments (4×4×2) and (2×2×2) for potency and repellence assessments, respectively, were laid out in a Complete Randomized Design (CRD) and replicated three (3) times to assess the impact of the different treatment combinations. Potency was assessed by counting emerged adults 60 days after treatment (DAT), while repellence was monitored during the first 5 hours post-application.The results showed that the treatment with 1.5g leaf powder + 0.0g seed powder + 0.00g Pirimiphos-methyl exhibited 100% potency effect (P ≤ 0.001), while the treatment with 0.5g leaf powder + 0.5g seed powder + 0.01g Pirimiphosmethyl  showed up to 90% repellence effect (P ≤ 0.01). The study highlighted that J.curcashave the potential to serve as a botanical insecticide for the sustainable management of C. subinnotatus in stored Bambara groundnut.