Juniperus macrocarpa: a Mediterranean resource against stored food insect pests

The Coleoptera Sitophilus oryzae (L.) (Curculionidae) and Cryptolestes ferrugineus (Steph.) (Laemophloeidae) are among the most important primary pests of all types of grain, pasta, flour, legumes, and tobacco. Essential oils, extracted from aromatic plants, due to their repellent properties and very low toxicity to mammalians, could represent a valid, alternative to chemical repellents for the protection of stored foodstuff. In this study, the essential oil extracted from Juniperus macrocarpa Sm. (Cupressaceae) (JEO), native of Mediterranean sand dune habitat, was chemically analyzed and its repellent activity against S. oryzae and C. ferrugineus was evaluated by the Area Preference Method. The results showed that JEO was constituted mainly by mono and sesquiterpene hydrocarbons. JEO major chemical was α-pinene, repeatedly reported as a very effective repellent against stored food insect pests. The bioassays indicated that JEO exerts a good repellency against S. oryzae and C. ferrugineus. Interestingly, C. ferrugineus is about 15 times more susceptible to JEO than S. oryzae. The obtained results showed that JEO could represents an effective, broad-spectrum bio-repellent to be used as sustainable alternative to synthetic insect repellents to fight the losses caused to stored food by insect pests.