Bioattività degli oli essenziali: luci e ombre del loro utilizzo nella gestione degli insetti dannosi

The repeated and indiscriminate use of synthetic insecticides to protect food from insect attacks has led to serious environmental and human health problems and has induced insecticides resistance in the target species. In recent years, many efforts have been made to investigate the insecticidal activity and the insect repellency of natural products, including essential oils (EOs). This latter, although very effective, are poorly applied in practice due to some practical problems, like the smell, or the variability of the bioactivity. Many EOs are very effective in repelling insects, but because very unpleasant to human olfactory system they cannot be used. To overcome this problem, in the manuscript, a preliminary sensorial screening of the EOs is proposed. With regard to bioactivity, among the factors that can influence the type and intensity of the effect there are certainly the insect species, the chemical composition and the dose of the OEs. Finally, since anti-acetylcholine esterase effect has been demonstrated for some EOs, a mode of action similar to the one of many neurotoxic insecticides such as carbamates and organophosphates, a particular attention must be paid to the problem of resistance.