Table of Contents
Journal of Insects
Volume 2014, Article ID 917212, 7 pages
http://dx.doi.org/10.1155/2014/917212
Research Article

Fumigation Toxicity of Essential Oil Monoterpenes to Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

1Department of Entomology and Plant Pathology, Auburn University, 301 Funchess Hall, Auburn, AL 36849-5413, USA
2Department of Biology, Storage Technology Programme, Federal University of Technology, PMB 704, Akure 34001, Nigeria

Received 19 June 2014; Revised 8 September 2014; Accepted 22 September 2014; Published 7 October 2014

Academic Editor: Fedai Erler

Copyright © 2014 Olufunmilayo E. Ajayi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The fumigant toxicity of eight essential oil components, 1-8-cineole, carvacrol, eugenol, (−)-menthone, (−)-linalool, S-(−)-limonene, (−)-β-pinene, and (+)-α-pinene, was tested against the cowpea weevil, Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae), at 0.25–60 µL/L air doses. 1-8-Cineole, carvacrol, and eugenol caused complete adult mortality at 10 µL/L air 24 h after treatment. 1-8-Cineole and carvacrol were the most toxic with LD50 values of 0.24 and 0.6 µL/L air at 24 h, respectively. (−)-β-Pinene and (+)-α-pinene were the least toxic with LD50 values of 31 and 31.4 µL/L air at 24 h, respectively. Toxicity was negatively correlated with vapor pressure. 1-8-Cineole and carvacrol caused 100% oviposition deterrence at all doses tested. Eugenol and (−)-menthone completely inhibited adult emergence. S-(−)-Limonene, (−)-β-pinene, and (+)-α-pinene were not effective at preventing oviposition or adult emergence, suggesting that a lethal dose of the three oil components would be necessary to control C. maculatus infestations.