Many pollinator-dependent crop plants are being cultivated very far from their original areas, having to cope with pollinator assemblages to which plants may be poorly adapted. This frequently pushes farmers to rely on domestic bees to ensure yield, summing an additional management action whose effectiveness is, in most cases, unknown. In our new paper in Agriculture, Ecosystems and Environment, we tackle this issue with exotic kiwi (from Asia) and blueberry (from North America) crops in northern Spain, evaluating pollinator assemblages, their effects on fruit production and their response to landscape features and domestic pollinator management.
We found that kiwi flowers were visited by more than 50 insect species, although domestic honeybees accounted for almost 70% of visits. Blueberry relied much more on wild pollinators than kiwi, as wild bumblebees represented between 50 and 90% of visits, depending on the cultivar. Both kiwi and blueberry yield depended on pollinators, but pollinators effects differed between crops, with a higher abundance of honeybees favoring kiwi fruit weight but a higher abundance of wild pollinators increasing blueberry fruit set and weight. Both the abundances of domestic honeybees and wild pollinators depended on the structure of the landscape surrounding orchards and, surprisingly, were unresponsive to the quantity of honeybee hives and blumblebee colonies installed by farmers.
Our research highlights the relevance of pollination ecology studies for evaluating how crops adapt to new farming environments, encouraging farmers to have first an eye on wild pollinators and their natural drivers, before setting domestic ones.