Contact Toxicity and Ovideterrent Activity of Three Essential Oil-Based Nano-Emulsions against the Olive Fruit Fly Bactrocera oleae

The control strategies for the olive crop key pest, Bactrocera oleae, involve synthetic chemical insecticides and few eco-sustainable alternatives, such as ovideterrents lures. In last decades, interest concerning formulation of botanical based biopesticides increased, but little research investigated suitability these approaches B. oleae control. This aimed to investigate residual contact toxicity oviposition deterrence three essential oil (EO)-based nano-emulsions (Pimpinella anisum, Foeniculum vulgare, Mentha × piperita) against adult flies. All possessed optimal physical characteristics, with droplets dimensions ranging from 115 152 nm low PDI values (<0.2), even after 1 year storage. Although no notable was noted, all tested formulations reduced number puncture in no-choice tests (percent repellence: mint < fennel anise). choice trials, olives treated anise EO-formulations at highest concentration (7.5%, 75 g EO/L) were less attractive respect fruits a significant reduction punctures recorded. Nano-biopesticides are promising eco-friendly tools integrate pest management programs reduce use harmful conventional active ingredients.