Effect of an insecticide-fungicide tank mix on bee activity and soybean yield

Soybeans (Glycine max) and bees have a mutually beneficial relationship where nectar is provided in exchange for pollination that can improve yield. However, pesticide use on soybeans during bloom could disrupt this relationship by harming bees and reducing yield increases from pollination. The aim of this project was to document the impact on bee foraging and soybean yield resulting from a pesticide application made at different times of day, mid-day and in the late afternoon, during peak bloom (R3), and after bloom has ended (R5). To do this, soybean plots were sprayed individually with a mixture of Fastac insecticide (10.9% alpha-cypermethrin) and Fitness fungicide (41.8% propiconazole) using a backpack sprayer. Plots were 5 feet by 28 feet, and were located in central Ohio. Bee activity data within each plot was documented through use of an audio recording device that records bee buzzing. Audio files were then analyzed for instances of bee buzzing by a specially trained machine learning model. Yield data was obtained through harvesting soybean plants and measuring the plot weight, plot moisture, and test weight. Through these measurements, we will be able to determine if pesticide applications have an effect on bee visitation and yield.