Nano‐Formulated Pyraclostrobin With Iron Bismuthide Enhances Efficient Utilization of Active Ingredient and Improves Biosafety

The widespread application of pyraclostrobin (PYR), an important strobilurin fungicide with low utilization efficiency, urgently requires optimization for sustainable agriculture. In this study, nanoformulated PYR with nano-iron bismuthide (FeBi) was successfully prepared via flash nanoprecipitation, yielding spherical PYR/FeBi nanoparticles (NPs, Φ120 nm) with stable drug loading capacity (67.9%) and controlled release. These NPs exhibited enhanced anti-Botrytis activity in vitro and superior in vivo performance. On tomato leaves, PYR/FeBi NPs at 80 µg/mL achieved greater than 90% curative and protective efficacy against Botrytis cinerea infection and significantly mitigated lesion expansion, surpassing commercial PYR suspension concentrate (SC) at equivalent concentrations. On tomato seedlings, PYR/FeBi NPs significantly reduced gray mold disease by 89%, compared to 67% with PYR SC at the same concentration. The mechanism underlying this enhanced activity involved stronger disruption of mitochondrial metabolism, including acetylation process, oxalate production, and damage to mycelia and conidia. Further, PYR/FeBi NPs displayed reduced cytotoxicity on human Hek293 and Chinese hamster V79 cells compared to PYR SC. The results highlighted the biocompatibility and potential of PYR/FeBi NPs for efficient utilization of active ingredients in sustainable agriculture.