Evaluation of biomass-derived pyrolysis oils as a source of pesticides for insect vectors of plant pathogens

Neonicotinoids and pyrethroids are commonly used pesticides against insect pests, including many species that are vectors of plant pathogens. However, these pesticides pose environmental and health risks, and for certain crops major buyers such as Walmart and Costco have begun to mandate that they will only purchase products grown without neonicotinoids at planting. Thus, there is a need to seek sustainable alternatives. While pyrolysis oils derived from biomass have shown emerging potential as pesticides, their application for pests specific to Washington State still needs to be explored. This study will focus on pyrolyzing residues from peppermint leaves, oregano leaves, and garlic waste to produce oils tested against pea aphids, beet leafhoppers, and potato psyllids—key vectors of crop pathogens. Oils showing pesticidal activity will undergo fractionation, preparatory HPLC, further testing, and characterization. Laboratory and greenhouse experiments will then validate their efficacy against each of the vector species, and assess plans for largescale production. Additionally, this project will provide training opportunities for a graduate student in Biological Systems Engineering, fostering future research expertise.