Due to concerns about frequent applications of spinosad and other broad spectrum insecticides for managing spotted-wing drosophila (Drosophila suzukii Matsumura, SWD), we investigated the use of essential oils as an alternative to current insecticides. Essential oils from a number of plant species have been studied for their attraction and deterrence of SWD. However, these botanical products have not been thoroughly tested in the field. We conducted laboratory and field studies to determine the efficacy of botanical products, including lavender (Lavandula angustifolia Mill.) oil, catnip (Nepeta cataria L.) oil, KeyPlex Ecotrol® PLUS, and KeyPlex Sporan® EC2 on preventing SWD infestation in raspberry (Rubus idaeus L.) and blueberry (Vaccinium corymbosum L.) crops. In a two-choice laboratory bioassay, lavender oil, Ecotrol, and Sporan treatments deterred SWD from a yeast-cornmeal-sugar based fly diet. In the field trials, raspberry fruit treated with Ecotrol had lower SWD infestation (6%), compared to the control (17%), and was comparable to spinosad (6%). No differences were seen in blueberry infestation. The combination of essential oils in Ecotrol may work to decrease SWD fruit infestation under certain conditions in the field, however more research is needed on the longevity of these products.
Bibliographical noteFunding Information:
Funding: Funding for this project was partially provided by the Minnesota Invasive Terrestrial Plants and Pests Center through the Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR), and Minnesota Department of Agriculture Agricultural Growth, Research, and Innovation (AGRI) Crops Research grant. Funding was also provided by the Minnesota Agriculture Experiment Station (MIN-21-077 and MIN-21-090) and the University of Minnesota Office of the Vice President for the Research Grant-in-Aid program.
- Integrated pest management
- Rubus idaeus
- Small fruit
- Vaccinium corymbosum
- Volatile organic compounds