Pollination by bumble bees is critical in the cultivation of many crops, for example tomatoes and strawberries. Year round glasshouse production of these crops in Northern areas, require use of artificial light, so far mainly High Pressure Sodium (HPS) lights. Unfortunately bumble bee’s vision is ill suited to this light and they cannot operate in this light spectrum without support from natural light.
Valoya’s AP67 light spectrum, for vegetative growth and flowering, differs from HPS light spectrum significantly. As this spectrum provides very good growth results with for example tomatoes and strawberry, it was important for Valoya to test how the bumble bees can work in this light.
Bumble bees have trichromatic vision which means that they can see three areas of the light spectrum. Research has shown they can see UVB, blue and green light. It is well known that bumble bees cannot operate under pure HPS light conditions, but require natural light to enable them to see and navigate between the plant flowers and their nests. This has limited the operational time of bumble bees to availability of natural light. During the dark winter months their working time, especially in the Nordic countries, is thus been reduced. Another issue with bumble bees and the HPS lights is the high temperature the fixtures generate. If a bumble bee hits the HPS fixture by accident, they are likely to get burned and terminally injured.
Valoya demonstrated the functionality of their lights in a tomato trial at PlantResearch in Made, Netherlands. The hatches of bumble bee hives in a HPS illuminated compartment and a compartment with Valoya AP67 light on, were opened 4 am, in mid-January, when there was no natural light yet available. The entry of the bumble bee hive was filmed with high speed cameras, for documentation of bee activity.
In the LED compartment the bumble bees started flying out to flowers, immediately when the AP67-LED lights were turned on, whereas in the HPS compartment with the lights on and the hatch open bumble bees started to operate 4 hours later when some natural light started to be available.
“We are currently researching and developing all aspects of our lights, including impact on both invited and uninvited insects. From other trials we know that aphids have a lower reproduction rate under our LEDs compared to HPS and red-blue LEDs, now we know that our lights are bee friendly.” comments Lars Aikala, CEO of Valoya.