title: Octanoic acid confers to royal jelly varroa-repellent properties.
abstract: The mite Varroa destructor Anderson & Trueman is a parasite of the honeybee Apis mellifera L. and represents a major threat for apiculture in the Western world. Reproduction takes place only inside bee brood cells that are invaded just before sealing; drone cells are preferred over worker cells, whereas queen cells are not normally invaded. Lower incidence of mites in queen cells is at least partly due to the deterrent activity of royal jelly. In this study, the repellent properties of royal jelly were investigated using a lab bioassay. Chemical analysis showed that octanoic acid is a major volatile component of royal jelly; by contrast, the concentration is much lower in drone and worker larval food. Bioassays, carried out under lab conditions, demonstrated that octanoic acid is repellent to the mite. Field studies in bee colonies confirmed that the compound may interfere with the process of cell invasion by the mite.
authors.affiliation: Dipartimento di Biologia e Protezione delle Piante, Università degli Studi di Udine, via delle Scienze 208, 33100, Udine, Italy. francesco.nazzi@uniud.it
authors.forename: Francesco
authors.initials: F
authors.lastname: Nazzi
authors.forename: Renzo
authors.initials: R
authors.lastname: Bortolomeazzi
authors.forename: Giorgio
authors.initials: G
authors.lastname: Della Vedova
authors.forename: Fabio
authors.initials: F
authors.lastname: Del Piccolo
authors.forename: Desiderato
authors.initials: D
authors.lastname: Annoscia
authors.forename: Norberto
authors.initials: N
authors.lastname: Milani
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology*; D002210:Caprylates / Q000032:analysis*; D005227:Fatty Acids; D005260:Female; D007301:Insect Hormones / Q000032:analysis*; D007305:Insecticide Resistance; D007558:Italy; D007814:Larva / Q000502:physiology; D055549:Volatile Organic Compounds / Q000032:analysis; D000099219:Royal Jelly
chemical_list: D002210:Caprylates; D005227:Fatty Acids; D007301:Insect Hormones; D055549:Volatile Organic Compounds; D000099219:Royal Jelly; C031492:octanoic acid