1,4-Dimethoxybenzene, a Floral Scent Compound in Willows that Attracts an Oligolectic Bee

Abstract

Many bees are oligolectic and collect pollen for their larvae only from one particular plant family or genus. Here, we identified flower scent compounds of two Salix species important for the attraction of the oligolectic bee Andrena vaga, which collects pollen only from Salix. Flower scent was collected by using dynamic-headspace methods from Salix caprea and S. atrocinerea, and the samples were subsequently analyzed by coupled gas chromatographic-electroantennographic detection (GC-EAD) to detect possible attractants of A. vaga. EAD active compounds were identified by gas chromatography coupled to mass spectrometry. Both Salix species had relatively similar scent profiles, and the antennae of male and female bees responded to at least 16 compounds, among them different benzenoids as well as oxygenated monoterpenoids and sesquiterpenoids. The strongest antennal responses were triggered by 1,4-dimethoxybenzene, and in field bioassays, this benzenoid attracted females of A. vaga at the beginning of its flight period, but not at the end.

Host recognition in a pollen-specialist bee: evidence for a genetic basis

“…In the light of earlier studies that demonstrated the importance of pollen odours in flower selection by the pollinating insects (e.g., Plateau, 1897;von Frisch, 1919), Linsley (1958) suggested that oligolectic bees could rely on pollen odours for host recognition, rather than, or in combination with, floral colour or morphology. Indeed, this was confirmed later for several oligolectic bee species (Dobson, 1987;Dobson and Bergström, 2000;Dötterl et al, 2005;Dötterl and Schäffler, 2007). The prediction of Linsley was based on the idea that "the only prior experience which the newly emerging solitary oligolege has had with its appropriate pollen source is the pollen and nectar which were stored by its parent" (Linsley, 1958).…”

Chemical composition and effect of an essential oil of Salix aegyptiaca L., Salicaceae, (musk willow) in hypercholesterolemic rabbit model

“…It occurs naturally in willow (Salix spp. ; Dötterl et al, 2005) and Zuchini (Cucurbita pepo;Mena Granero et al, 2005). The remarkable behavioral change that has been reported following intake of DMB in mice was somnolence as a general depressed activity (Sigma Aldrich, 2004).…”

Evaluation of oligolecty in the Brazilian beePtilothrixplumata(Hymenoptera, Apidae, Emphorini)

“…The repetitive selective of certain specific food plants by females of an oligolectic species, however, points to a genetically influenced characteristic of the bee species. Recently it was shown that specific substances in the floral odor of host plants seem to be chemical markers for oligolectic bees (Dötterl et al, 2005;Füssel et al, 2007). This could be true also for the Pavonia -Ptilothrix -Pristimerus association.…”