Farmers of broad beans in Ireland would benefit from reduced pesticide use and the creation of habitats for wild bumblebee populations to secure the best possible marketable crop yields.
While honeybee populations might aid pollination, seasonally introduced or nearby year-round, it is the wild bumblebees that accounts for around 70% of the marketable yield. This is according to new research published today (31 January 2023) in the Royal Entomological Society (RES) journal Agricultural and Forest Entomology and conducted by Dr Katherine Burns and Dr Dara Anne Stanley from the School of Agriculture & Food Science at University College Dublin. It comes just days after it was suggested by researchers at University of Reading, that using broad bean flour in commercial bread production could offer significant environmental and nutritional benefits.
Though broad beans (also known as faba or fava beans) are capable of self-pollination, several studies have indicated that insect pollinators significantly increase yields. This new research, the first to study identifiable insect pollination of broad beans in Ireland, finds that wild bumblebee pollination contributes most significantly to the crop’s production value. Insect pollination accounts for almost half of Ireland’s total broad bean market value, with the pollinator contribution estimated at almost €4,000,000 per year. Relative to other pollinators, wild bumblebees contribute to around 70% of the economic value of pollinated broad beans, driven mainly by the long-tongued species Bombus hortorum, which is best adapted to the long-corollae flowers of broad beans.
Speaking about the findings of the research, which was conducted in eight conventionally managed broad bean fields in Southeast Ireland in 2018 and 2019, Dr Katherine Burns said:
“With this research we wanted to quantify the contributions of insect pollinators to what is a hugely valuable crop here in Ireland to better understand how pollinators should be managed and protected. We found that wild bumblebees are overwhelmingly the most important pollinator of broad beans and that plants pollinated by wild bumblebees, which are less abundant but much more effective, accounted for most of the marketable bean yields.”
Commenting on the potential significance of this new research, Dr Adam Vanbergen of INRAE and the Royal Entomological Society, said:
“We support the recommendations of this research for farmers to prioritise the welfare of wild bumblebees, not only to improve the economic viability of their crops, but also to secure the long-term survival of a wild pollinator also important for wild plants. We can see that these findings may stimulate land management research and applications encouraging researchers and the agricultural sector (farmers, agri-business, and retailers) to work together to assure crop yields whilst conserving vital wild pollinator biodiversity.”
The full research paper can be found here.