Termiticidal activity of oil from Jatropha curcas L. and Azadirachta indica A. Juss against Coptotermes sjostedti Holmgren (Isoptera: Rhinotermitidae)

Abstract

BackgroundCoptotermes sjostedti Holmgren (Isoptera:Rhinotermitidae) is one of the major termite species found infesting woods and other plant materials in Africa. Bioassays were carried out at the Arboretum of the Department of Forestry and Wildlife Resources Management, University of Calabar, Nigeria to investigate the effect of oils from the kernel of Jatropha curcas L. and Azadirachta indica oils A. Juss against the African subterranean termite (Coptotermes sjostedti Holmgren). Treatments comprised of the plant oils and Solignum (a synthetic termiticide, serving as positive control) applied at the rate of 5, 10 and 15 mL per 100 cm3 of the wood from seven plant species. Untreated woods also served as control. Seven wood species were placed in a test arena and artificially infested with 50 termites per unit. The setup was a randomized complete block design with four replicates. Data on termite mortality and wood weight loss were recorded.ResultsThe use of 10 and 15 mL of J. curcas oil caused more than 90% mortality of C. sjostedti, after 96 h, kept wood consumption by the insect below 6.0% after 3 months, and these outcomes were similar to that of Solignum at the same concentrations. About 35.0–65.2% reduction in weight was observed among untreated woods from the tested woods, indicating their susceptibility to C. sjostedti attacks. Correlation analysis shows a significant (r > − 0.900; P < 0.0001) negative association between termite mortality and the rate of wood consumption.ConclusionThe use of J. curcas oil at 10 mL per 100 cm3 of wood could be a potent alternative to Solignum for the control of C. sjostedti.