Keyrole of the foeraging behaviour of bumble bees in the biological control of plant pathogens (Botrytis cinerea)

Since several decades bumblebees have been used in greenhouses for the pollination of crops and fruits like strawberries. The advantage of natural pollinations is an improvement of the fruit quality. Furthermore, due to the use of bumblebees, the growing public concern towards the conventional fungicides for the environment and the residual risks and the development of resistant strains, there is an urgent need for alternatives to control world important plant pathogens like the grey mold Botrytis cinerea. A promising solution to these problems is the employment of biological control agents (BCAs). For instance, Trichoderma species have proved under laboratory conditions to be capable to control B. cinerea. However, in the field spray applications failed to control the plant pathogen. In this project we will investigate the ability of bumblebees to disseminate conidia of T. harzianum and T. polysporum from hive-mounted dispensers to greenhouse strawberries for the control of B. cinerea. We will work with the four most important bumblebee species: Bombus terrestris, Bombus ignitus, Bombus canadiensis and Bombus occidentalis
At first we will evaluate the compatibility of the BCAs, the transport capacity and the survival of the conidia in the flowers. At last the biological system will be tested under practical conditions. This research project is unique because the pollinator-vector technology is a novel and challenging example of integrating agro-ecosystem processes of pollinating and integrated pest management strategies to reduce the reliance on fungicides and to increase crop yields and quality.