title: Major changes in the sex differences in cuticular chemical profiles of the western conifer seed bug (Leptoglossus occidentalis) after laboratory rearing.
abstract: Chemical compounds covering the insect cuticle have several functions ranging from protection against water loss to inter- and intra-specific communication. Their composition is determined by several intrinsic and extrinsic factors. Among these factors, laboratory rearing has been poorly investigated even though it has a strong potential for biasing behavioral experiments. We selected an invasive species with unknown cuticular mixtures as a model. Our aim was to describe its mixtures and to determine if highly simplified laboratory rearing conditions interact with sexual signatures. We analyzed the cuticle by means of two different techniques - gas chromatography/mass spectrometry (GC/MS) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) - to obtain data on a wide range of compounds with different molecular weight. We found that both sets of chemicals showed correlations with gender but also that cuticular waxes detected by GC/MS were highly dependent on rearing conditions, with a strong bias in sexual dimorphism. Conversely, the heavier signatures detected by MALDI-TOF showed a less clear diversification between sexes, although the discrimination power was unaffected by rearing conditions. The biological and practical implications of our findings are discussed.
authors.affiliation: Dipartimento di Biotecnologie Agrarie, Sezione di Protezione delle Piante, Università degli Studi di Firenze, Firenze, Italy. leondap@gmail.com
authors.forename: Leonardo
authors.initials: L
authors.lastname: Dapporto
authors.forename: David
authors.initials: D
authors.lastname: Baracchi
authors.forename: Daniele
authors.initials: D
authors.lastname: Benassai
authors.forename: Paolo
authors.initials: P
authors.lastname: Capretti
authors.forename: Pio Federico
authors.initials: PF
authors.lastname: Roversi
authors.forename: Stefano
authors.initials: S
authors.lastname: Turillazzi
mesh_terms: D000818:Animals; D001947:Breeding / Q000379:methods*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D020062:Heteroptera / Q000737:chemistry* / Q000254:growth & development / Q000502:physiology*; D019476:Insect Proteins / Q000737:chemistry*; D007753:Laboratories; D008297:Male; D012727:Sex Characteristics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D019476:Insect Proteins; C047663:cuticle proteins, insects