Evaluation of some Plant Powders as Natural Biopesticides Against Maize Weevil Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae)

Abstract

The study investigated the bioactivity of Curcuma longa, Azadirachta indica, Eucalyptus globulus, Capsicum annum, Icacina senegalensis, Moringa oleifera and Piper guineense plant powders obtained in the Gambia against the maize weevil Sitophilus zeamais at concentrations of 2.5, 5.0 and 10.0% (w/w) in a Randomized Complete Block Design with four replicates. Data were collected on adult mortality, F1 progeny emergence, number of eggs laid, grain weight loss and damage to determine the potency of the botanicals. Piper guineense, Azadirachta indica and Eucalyptus globulus were the most bioactive against S. zeamais at 10%. The application of P. guineense caused higher mortality and inhibition rates and lower weight loss and oviposition, with respective values of 100, 98.50, 0.03, and 0.00%. Piper guineense was the most potent plant powder against the maize weevil, hence promising for its control.