Do floral odor profiles geographically vary with the degree of specificity for pollinators? Investigation in two sapromyophilous Arum species (Araceae)

Marion Chartier (1) , Laurent Pélozuelo (2) , Marc Gibernau (1)

1 ECOFOG - Ecologie des forêts de Guyane
2 LEFE - Laboratoire Ecologie Fonctionnelle et Environnement

We compared floral odour profiles among populations of two Arum species which show different degrees of specificity for their fly pollinators. Insects were collected from inflorescences in four populations of Arum italicum and two populations of Arum maculaturn. In six Arum populations, we compared inflorescences odour profiles collected by Solid Phase Micro Extraction (SPME) and analysed by gas chromatography. We confirmed that from a pollination point of view, A. italicum is an opportunist species, as it is mainly pollinated by insects of the families Psychodidae, Chironomidae and Sciaridae, whereas A. maculatum is a specialist species, as it is 90% pollinated by Psychodidae. In all populations, Arum italicum was less attractive to pollinators than Arum maculatum. Floral odour profiles of A. italicum were not geographically structured among populations, suggesting a high gene flow or adaptation to a fluctuant guild of pollinators. On the contrary, odour profiles of A. maculatum varied between the two populations studied suggesting a lower gene flow or adaptation to different local pollinator preferences

Mots clés: PSYCHODIDAE; ARUM ITALICUM; ARUM MACULATUM; ODEUR FLORALE; MOUCHE POLLINISATRICE; FLORAL SCENT; SPECIFITY

Domaines: Biodiversité

Marion Chartier, Laurent Pélozuelo, Marc Gibernau. Do floral odor profiles geographically vary with the degree of specificity for pollinators? Investigation in two sapromyophilous Arum species (Araceae). Annales de la Société Entomologique de France, 2011, 47 (1-2), pp.71-77. ⟨hal-01019003⟩