Repellent Effect and Insecticidal Activities ofBridelia ferruginea,Blighia sapida, andKhaya senegalensisLeaves Powders and Extracts againstDinoderus porcellusin Infested Dried Yam Chips

Abstract

Dinoderus porcellusis considered as the most important pest of stored yam chips and compounds extracted from plants can be used for its control. The present study aimed to test the insecticidal and repellent activities of powders and extracts of leaves ofBridelia ferruginea,Blighia sapida, andKhaya senegalensisagainstD. porcellus. The efficacy of plant powders was compared with the synthetic pesticide Antouka (Permethrin 3 g/kg + pirimiphos 16 g/kg). The results of the experiment revealed that all plant powders were effective as repellents. Antouka was more effective as insecticidal than the plant powders and minimal weight loss was observed withB. sapidaat 2%. Among treatments, propanol extract ofK. senegalensisat 5% was found to elicit the highest repellent effect onD. porcellus. The LC₅₀results revealed that the acetone extract ofK. senegalensisis the most toxic (0.29 μL/insect) to the pest, while the propanol extract ofB. ferrugineaat 5% exhibited strong fumigant toxicity againstD. porcellus, with 88.89% of pest mortality at 160 μL/L air. The findings from the current work proved that plant powders and extracts of the three plants are sources of botanical insecticides which may be used in the integrated management ofD. porcellus.