Pistacia lentiscus essential oil has repellent effect against three major insect pests of pasta

Rhyzopertha dominica, Sitophilus zeamais, and Tribolium confusum are three of the major food-stuff pests who cause important economic losses of shelved products with special reference to pasta. Due to its long shelf life, pasta is highly exposed to insects that can penetrate into the packaging with consequences economically severe. Eco-friendly strategies to prevent such insect attacks to the final packaged product are therefore highly foreseen by pasta companies. Due to their repellent properties, essential oils, extracted from aromatic plants, could represent a valid, eco-friendly alternative to chemical repellents. In this study, we evaluated the repellent activity of Pistacia lentiscus essential oil (PEO) and its main chemical components by two different bioassay with and without the presence of pasta. Results showed that the whole PEO exerts a broad-range aspecific repellency among the target pests with RD50 values ranging from 0.010 to 0.037 μL cm−2. On the contrary, the repellence of PEO components resulted to vary depending on the compound and on the pest species. Among the PEO chemical components, relative median potency analyses indicated that β-caryophyllene was able to exert the highest repellency rates against S. zeamais (RD50 0.046 μM cm−2). The comparison between the two bioassays, with and without pasta, indicated that the two methodologies gave consistent results. Overall, our research firstly showed that, because of their effectiveness as repellents, PEO and its major constituents could represent valid and safe tools against pasta pests