Chemical deception

bees and lime trees

Plants can chemically manipulate pollinator behaviour against the pollinators' best interests, to optimize pollination services at minimal cost. Bee orchids (Ophrys spp.) offer bees no nectar reward, but instead mimic female bee sex pheromones to trick corresponding male bees into visiting and transferring pollen [70]. Other plant species may still offer nectar rewards, but chemically induce pollinators to over-value these rewards and visit with greater frequency than would be optimal for pollinators [42].

Despite the continued interest in the bee deaths on T. tomentosa, the floral chemistry including nectar, pollen and floral volatiles remains understudied. Bumblebees, and to a lesser extent honeybees, are attracted to linden even at the end of the flowering period, when little nectar is produced [39]. The potent scent of T. tomentosa has long been noted [21]. Illies [13] speculated T. tomentosa scent may mimic unknown bumblebee pheromones, causing