Ingestion toxicity of three Lamiaceae essential oils incorporated in protein baits against the olive fruit fly, Bactrocera oleae (Rossi) (Diptera Tephritidae)

Abstract

The ingestion toxicity of three Lamiaceae essential oils (EOs) – Hyptis suaveolens, Rosmarinus officinalis and Lavandula angustifolia – incorporated in protein baits was evaluated against Bactrocera oleae, a worldwide pest of olive fruits. In laboratory conditions, all the tested EOs showed dose-dependent toxicity on B. oleae, with mortality rates ranging from 12% (EO concentration: 0.01% w:v) to 100% (EO concentration: 1.75% w:v). Semi-field results highlighted the toxicity of L. angustifolia and H. suaveolens EOs, which exerted more than 60% of flies mortality at a concentration of 1.75% (w:v). Gas Chromatography-Electron Impact Mass Spectrometry analyses of the three EOs showed that H. suaveolens EO was dominated by monoterpene and sesquiterpene hydrocarbons. Oxygenated monoterpenes were the main chemical class in R. officinalis and L. angustifolia EOs. Further research is needed to evaluate the efficacy of these EOs plus food bait against the olive fruit fly in the open field.