African Journal of Biotechnology Vol. 5 (21), pp. 2032-2036, 2 November 2006   

ISSN 1684–5315 © 2006 Academic Journals        

Full Length Research Paper

Laboratory evaluation of four medicinal plants as protectants against the maize weevil, Sitophilus zeamais (Mots)

S. T. Arannilewa¹*, T. Ekrakene² and J. O. Akinneye¹

¹Food Storage Technology Programme, Department of Biology, Federal University of Technology, P.M.B 704, Akure, Nigeria.

²Basic Science Department, Benson Idahosa University, P.M.B 1100, Benin City, Nigeria.

*Corresponding authors E-mail: lolunig@yahoo.com .

Accepted 11 July, 2006

The petroleum ether extract of four medicinal plants; Aristolochia ringens (Vahl), Allium sativum (L), Ficus exasperata (L) and Garcinia kola (H), were evaluated as grain protectant against the maize weevil, Sitophilus zeamais (Mots) in the laboratory at 0.5, 1.0 and 1.5% (w/v) concentrations. Parameters assessed were adult mortality, rate of adult emergence, grain damage effect and weevil peforation index (WPI). There was increase in adult mortality with days of exposure in all concentrations. Ar. ringens followed by Al. sativum were most potent both in adult mortality and adult emergence. This study reveals Ar. ringens to be a potent bioinsecticide for protecting maize grains from S. zeamais infestation and damage. The details of the bioassay procedure used and the results obtained are reported.

Key words:  Medicinal plants, bioinsecticide, Aristolochia ringens, Sitophilus zeamais, weevil perforation index.