Department of Plant Physiology, Institute for Biology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Worringerweg 1, D-52056 Aachen, Germany; Department of Plant Health Management, Michael Okpara University of Agriculture Umudike,
Nwachukwu, I.D., Department of Plant Physiology, Institute for Biology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Worringerweg 1, D-52056 Aachen, Germany; Asawalam, E.F., Department of Plant Health Management, Michael Okpara University of Agriculture Umudike, P.M.B. 7267 Umuahia, Nigeria
Freshly prepared garlic (Allium sativum L.) juice, containing the antimicrobial allicin, was evaluated as a possible grain protectant against the maize weevil, Sitophilus zeamais (Motsch.). Each experiment was set out in Completely Randomized Design (CRD) with four replications, and there was a control treatment. Adult mortality and weight loss percentage were investigated. There was an observed increase in adult mortality following days of exposure in all treatments. Statistically significant (p < 0.05) reduced grain loss was also observed in all the treatments when compared with the control. The juice samples were freshly prepared from an indigenous Nigerian garlic cultivar (GUN) and a cultivar purchased from a supermarket in Germany (GAG). These garlic juice samples exhibited lethal effects causing at least 90% adult mortality in contact toxicity tests. The amount of allicin in GUN was 1.88 mg/ml according to High Pressure Liquids Chromatography (HPLC) analysis, while the amount of allicin in GAG was 3.50 mg/ml. This study highlights the potential of A. sativum containing allicin for biorational control of maize grains against S. zeamais infestation and damage.
