双金属CuZn纳米酶破坏细菌氧化还原平衡，实现植物病害控制

Abstract

CuZn@DEG kills bacteria via membrane disruption, ROS generation and DNA damage. • The nanoparticles effectively inhibit biofilm formation and antioxidant defenses. • CuZn@DEG effectively controls tomato bacterial wilt and rice bacterial leaf blight in vivo . • CuZn@DEG exhibits good biosafety toward crops and non-target organisms. Plant bacterial diseases pose a persistent threat to global crop production, resulting in substantial yield losses and highlighting the urgent need for effective and environmentally sustainable control strategies. Here, bimetallic copper–zinc nanoparticles (CuZn@DEG NPs) were synthesized and evaluated as antibacterial nanoagents for plant disease management. In vitro assays showed that CuZn@DEG NPs effectively inhibited the growth and proliferation of Ralstonia solanacearum ( R. solanacearum ) and Xanthomonas oryzae pv. oryzae ( Xoo ). Correspondingly, greenhouse experiments demonstrated effective control of tomato bacterial wilt and rice bacterial leaf blight, with performance comparable to commercial bactericides. Mechanistic studies revealed that CuZn@DEG NPs exhibit peroxidase-like (POD-like) catalytic activity, leading to excessive reactive oxygen species (ROS) generation, disruption of bacterial antioxidant homeostasis, and severe damage to cell membranes and genomic DNA, ultimately resulting in bacterial cell death. In addition, CuZn@DEG NPs significantly suppressed bacterial biofilm formation, thereby reducing pathogen virulence potential. Biosafety evaluations indicated no detectable phytotoxicity and negligible adverse effects on non-target organisms, including honeybees. Collectively, these results establish CuZn@DEG NPs as effective antibacterial nanoagents with favorable biosafety profiles for plant disease management.