Antifeedant Effects of Some Essential Oils on<i>Ceratitis capitata</i>Wied. (Diptera, Tephritidae)

Abstract

Abstract The effects of some essential oils of different chemical composition on amphigean adult Ceratitis capitata Diptera Tephritidae which causes serious damage to fruit crops has been reported here. The toxicity produced by oral administration of emulsions containing the active principles can be correlated to the type and concentration of the different compounds. The most effective, in terms of mortality rate, were the oils of Thymus herba-barona and Cinnamomum zeylanicum, which are rich in phenolic compounds (carvacrol) and aromatic aldehydes (cinnamic aldehyde). Over 90% mortality was obtained with emulsions containing 5% of these active principles. Under the same experimental conditions, Salvia officinalis oil, characterized by relatively high concentrations of monoterpenic ketones (camphor and thujone), produced mortality of close to 50%. The toxicity of Rosmarinus officinalis oil containing high concentrations of monoterpene hydrocarbons was much lower. The insecticidal effect produced by oral administration of the compounds tested appears to be correlated to irreversible damage to the gut of the medfly.