Do Apis and non-Apis bees provide a similar contribution to crop production with different levels of pollination dependency? A review using meta-analysis

1. Recent studies have demonstrated that the richness of pollinators in crop systems can improve productivity due to the effect of functional trait differences between species. These findings reinforce the potential effectiveness of integrated management of both Apis and non-Apis bees to ensure global crop yields. 2. Thus, we used meta-analysis techniques to synthesise published literature on crop pollination and verify whether Apis and non-Apis bees perform equivalent contributions to worldwide crop production considering the differences in both functional traits of these bees and pollination requirements of the crops. We expected that pollination by both Apis and non-Apis bees would contribute to enhancing all crop production measures (fruit/seed weight, fruit/seed yield, no. fruit/seed, and pollination/fertilisation) independently of levels of pollination dependency. 3. The final database used in the meta-analysis included 33 published studies, reporting 72 independent pollination experiments of A. mellifera and non-Apis bees on crop production, including fruits, vegetables, spices, and oil crops. As expected, our results demonstrated that crop production was greater with bee pollination regardless of being provided by Apis or non-Apis species. We also observed a stronger positive effect on flower pollination/fertilisation and production of crops with essential/great dependency on pollination. 4. The overall analysis of the contribution of Apis and non-Apis bees to crop production indicated that both groups are essential for the maintenance of agricultural production.