Carrier‐free co‐delivery nanosystem based on prothioconazole and pyrimethanil to enhance fungicidal efficacy and reduce environmental risks

Abstract BACKGROUND The conventional application of fungicides suffers from substantial off‐target loss due to photolysis, evaporation, and rain washing, resulting in risks to the environment and human health. To address these limitations, self‐assembled nanopesticides based on two kinds of fungicides have emerged as precision agrochemical delivery platforms that synchronize enhanced bioactivity with environmental risk mitigation. RESULTS Herein, core‐shell structured nanoparticles (PRO‐PYR NPs) with an average particle size of 263 nm were fabricated based on prothioconazole (PRO) and pyrimethanil (PYR) via non‐covalent interactions using co‐assembly technology. The co‐delivery system with acid‐responsive release property enhanced both antifungal activities against Botrytis cinerea and Fusarium graminearum and duration against Botrytis cinerea . Importantly, the obtained PRO‐PYR NPs could significantly improve photostability and foliage adhesion of fungicides and reduce their volatility and leaching potential. Additionally, the PRO‐PYR NPs reduced genotoxicity of PRO and PYR to the root tip cells of Vicia faba and acute toxicity to zebrafish. CONCLUSION The core‐shell structured nanoparticles based on two commonly used fungicides were successfully prepared by co‐assembly technology to effectively improve the physicochemical properties. Carrier‐free co‐delivery strategy based on multiple components of fungicides could effectively enhance the control effect and lower the negative impacts associated with non‐target organisms and environment for integrated pest management. © 2025 Society of Chemical Industry.