Gender-biased nectar targets different behavioural traits of flower visitors

Floral nectar is a chemically complex aqueous solution within which several secondary metabolites have been identified that affect attractiveness for pollinators. Understanding preferences and aversions to quality in flower visitors crucial since this may influence the patterns of insect floral visitation with consequences on plant fitness. We hypothesise chemical variation through different sexual phases number visits each phase receives. The study was realized population Echium vulgare L. growing natural area close Bologna. Nectar collected from functionally male female flowers investigate its composition HPLC technique. A total 200 min behavioural observations foraging insects also carried out. Variation traits has detected amino acid spectrum. proportion protein acids appeared be significantly higher male-phase flowers. This explain than expected observed all bee taxa (except Hoplitis adunca females). Functionally presented concentrations phenylalanine, whilst proline highly represented Since recent demonstrated hymenopterans can oxidize at high rate ATP production, we offered by two sexually distinct targets likely ensures an optimal pattern visit among sexes, are unequally distributed individuals population.