Abstract
The productivity and quality of three quarters our food crops, including those that provide the key nutrients we need, depend on insect pollination. Crop yield is commonly pollen-limited despite the use of managed pollinators, but recent studies have shown that crop pollination by rich wild pollinator communities can solve this problem. However, we have a poor understanding of the mechanisms by which higher pollinator diversity translates into higher productivity. Whereas physical pollinator trait complementarity has been the main hypothesis tested so far, I predict that diversity effects mainly act through differences between species in three behavioural traits: flower handling behaviour, optimum activity temperature and optimum activity time of day. More specifically, I aim to understand (1) whether behavioural diversity is more strongly related to fruit size and quality than species diversity, (2) what is the relative importance of these behavioural traits for fruit size and quality, and (3) whether we can use species behavioural traits to predict pollination effects on fruit size and quality. I will answer these questions through a semi-experimental approach, using strawberry as model crop for being the most widely cultivated berry in the world and strongly dependent on insect pollination. The study will comprise data collection in real-world farming systems and exclusion experiments, that will provide a deeper understanding on the abundance and richness of pollinators required for optimal pollination and the extent to which managed or wild species are needed.
Netherlands