Research Scientist Agriculture and Agri-Food Canada Vineland Station, Ontario, Canada
Spotted-wing drosophila (Drosophila suzukii) was found in North America almost 15 years ago and continues to be a priority pest in berry crops. In Ontario and Quebec, Canada, biological control research has focused on predators and natural enemy combinations. The rove beetle predator, Dalotia coriaria consumed 1st instar larvae but few 3rd instars. The predator Dicyphus hesperus consumed eggs, Podisus maculiventris consumed larvae, and Orius insidiosus and Chysoperla carnea fed on eggs and larvae and were the most efficient predators. We also found that the generalist pupal parasitoid Muscidifurax raptorellus was effective against D. suzukii. Combining M. raptorellus, O. insidiosus and C. carnea resulted in positive intraguild interactions and a 70% reduction in D. suzukii. Intraguild predation did not occur among these three natural enemies in choice and no choice tests. Sweet alyssum flower volatiles repelled D. suzukii, and the flowers may also benefit natural enemies, as Pachycrepoideus vindemmiae adults lived as long on flowers as when given honey. Assessing alyssum flower benefits to Leptopilina japonica, Ganaspis brasiliensis, M. raptorellus and predators is underway or being planned. As some berry growers already use sweet alyssum for attracting Orius against thrips, its use may optimized to also benefit D. suzukii biological control.
