Pollinators, particularly bees, are of crucial importance for apple pollination, as most varieties require cross‐pollination with compatible polliniser trees to set fruits. Although a large number of wild bee species have been recorded visiting apple flowers, we do not have information on whether different varieties attract distinctive communities of flower visitors, and whether this is related to varying levels of dependency on cross pollination.
The overall objective of this research is to compare the abundance, diversity and community structure of flower visitors in apple orchards between varieties and countries. We hypothesise that i) varieties vary in their dependency on cross pollination and insect visitation, ii) the diversity of visitor communities differs between varieties and that iii) the structure of these communities varies
across Europe.
We investigated these questions in four locations (UK, Germany North, Germany South and Hungary). For the first hypothesis, we carried out bagging experiments on five varieties. Pollination treatments included hand pollination with cross and self pollen, no pollination, wind pollination and open pollination. For the second hypothesis, we surveyed the abundance and diversity of insect species visiting flowers in eight apple varieties in commercial orchards using transects and timed tree observations. For the third hypothesis, we selected a variety common to all study countries and
carried out the same surveys as for the second hypothesis.
Here we present preliminary results from this study and discuss the implications that variability in both breeding systems and visitor communities has on orchard production.