Aphids are an economically damaging pest for several crops. This study aimed to explore the practicality of using insectary plants to attract predatory hoverflies to help manage aphids in Brassica crops. Our overall goal was to understand how insectary plants are used by hoverfly species in our region over time, and to determine which hoverfly species are present in the region.
We found that Alyssum, buckwheat, cilantro, and dill had more hoverflies throughout the season than calendula, phacelia, and fennel. In particular, alyssum was a low maintenance plant that continuously flowered and attracted the hoverfly Toxomerus marginatus from July until frost. Some of the insectary plants did host important brassica pests, such as flea beetle (alyssum) and imported cabbageworm (calendula). Additional work is needed to determine whether hoverflies present on insectary plants make meaningful contributions to biological control of aphid (or other) crop pests. You can read the full report here.
This project was part of the Brassica Pest Collaborative, and was supported by the USDA National Institute of Food and Agriculture Hatch Project NH00635, and by Northeast Sustainable Agriculture Research and Education project number LNE18-365, and The NH Vegetable and Berry Growers’ Association, and UNH Cooperative Extension.