Control of <i>Sitophilus zeamais</i> Motschulsky (Coleoptera: Curculionidae) with local plant materials in the western highlands of Cameroon

Abstract

Sitophilus zeamais Motschulsky is the main insect damaging stored maize in the western highlands of Cameroon. High cost, unreliable supply and environmental hazards of chemical insecticides necessitate search for cheaper, safe and easily available local alternatives. This study identifies and evaluates some local plant materials for control of S. zeamais. Field survey and laboratory studies were conducted and four plant materials consisting of leaves and/or roots; Cupressus arizonica, Eucalyptus grandis, Ocimum gratissimum and Vetiveria zizanioides identified were powdered and investigated. The experimental design used was randomized complete block. Data collected were analysed using F-test and significant means
were separated using Least Significant Difference. The powdered plant materials showed no significant toxicity against F1 progeny but V. zizanioides significantly (P 0.01) repelled S. zeamais, giving . 50% at the lowest dosage of 0.1g/25g grains. V. zizanioides root powder had potential for control of S. zeamais as repellent. This could form part of an integrated pest management package for the Western highlands of Cameroon.

Keywords: Survey, Vetiveria zizanioides, Sitophilus zeamais, control, maize, Cameroon