D3048: (1st Place) Biofumigation effects on non-target organisms: Determining host-mediated impacts on aboveground insects following biofumigation

Biofumigation, which involves incorporating plants (or plant products) from the family Brassicaceae to release biologically active compounds into the soil, is considered an eco-friendly pest control method practiced in organic and conventional production systems. While biofumigation can negatively impact subterranean pest populations, only limited information about their potential impacts on aboveground insects (pest or beneficial) is available. We conducted a series of laboratory petri dish bioassays to demonstrate the negative effects of biofumigation on springtails (Folsomia candida, collembola) as a model soil-dwelling non-target

organism. The brown mustard Brassica juncea (L.) Czem defatted seed meal caused 100% mortality in collembola within 24 hours of application. Incorporating brown mustard foliar tissue also negatively affected the survivorship of the collembola, and the effect was significantly influenced by the amount of aboveground tissue mixed in the soil (r = -0.9, P < 0.001). To evaluate host-mediated effects on aboveground insects, we will set up replicated (15 pots/treatment) greenhouse bioassays, including the 4 treatments of canola (B. napus) and brown mustard plants, brown mustard seed meal, and a non-treated control. Wheat will be planted two weeks after soil incorporation of our treatments. Five 2^nd instar bird cherry-oat aphids (Rhopalosiphum padi L.) will be introduced onto the wheat, 2 weeks after emergence. Aphid survival and reproduction will be recorded. Data collection and analyses will be finalized by the time of our poster presentation. Findings from this research will benefit farmers interested in implementing environmentally friendly and effective pest management strategies that can contribute to production sustainability.