Abstract for: Persistence of Pesticide Use in Quebec Field Crops: A Participatory Modeling Approach Using Causal Loop Diagrams to understand leverage policies point

Despite four successive regulatory frameworks since 1992, Quebec's agricultural pesticide sales have not significantly declined and Integrated Pest Management (IPM) adoption remains low in field crops. This study explains why successive reduction policies failed and identifies higher-leverage intervention points by revealing the feedback structures maintaining pesticide dependency in Quebec's corn-soybean sector (Montérégie-Est). A participatory qualitative Causal Loop Diagram (CLD) was constructed through individual interviews with 30 stakeholders primarly analysed (agri-food industry, regulators, NGOs, experts) and two group validation sessions following Group Model Building protocols. The resulting CLD was analyzed through leverage point hierarchy to assess intervention depth and identify structural policy gaps. Three competitions sustain lock-in: industry lobbying captures regulatory processes before environmental pressure generates binding policy; phytosanitary supply continuously adapts to resistance, maintaining chemical viability; and financial constraints eliminate producers' capacity to transition. These dynamics operate across economic, cognitive, and ecological dimensions simultaneously. Stakeholders proposed higher-leverage interventions such as crop insurance redesign, agronomist institutional reform, and alternative development networks, targeting structural roots of dependency rather than its symptoms. This first participatory systems analysis of Quebec field crop pesticide dependency demonstrates that policy failure results from compound sociotechnical lock-in, not only inadequate knowledge of alternatives. The CLD shows that individually documented adoption barriers (social norms, risk perceptions, perceived complexity) are interconnected elements of self-reinforcing feedback structures. Effective transformation requires coordinated intervention addressing lock-in depts, political asymmetries, and heterogeneous stakeholder constraints simultaneously. For translating and correction of sentences