Résumé
In Europe, 80% of crop species are dependent upon or benefit from pollination by insects, and mostly bees. Insect pollination is both a major ecosystem service that contributes to human well-being and a production practice used by farmers. Wild bees contribute to the pollination of most crop species and their importance are increasingly recognised since their foraging activity as well as their interaction with honey bees can significantly enhance the overall pollinating activity. Yet significant declines have been reported for wild bee populations and honey bee colonies alike in Europe. We quantified the relative importance of autonomous self-pollination, wind pollination and the pollination service provided by insects in annual entomophilous field crops over 7 to 10 sites located over a gradient of increasing semi-natural habitats in five pairs of crop-European country (ALARM EU project) : buckwheat Fagopyrum esculentum in Poland, cantaloupe Cucumis melo in France, field bean Vicia faba in the UK, spring oilseed rape Brassica napus in Sweden, and strawberry Fragaria x ananassa in Germany. Pollination service was measured on a whole plant basis, rather than using flower samples, so as to have direct access to yield data as well the quality and value of the production. Based on these results and also a larger review (Klein et al. 2007. Proc. Roy. Soc. B. 274:303-313), the potential impacts of pollinator decline on European agriculture will be presented in agronomic terms and also in terms of economic vulnerability.