Zeolitic imidazolate framework-8 nanoparticles: A promising nano-antimicrobial agent for sustainable management of bacterial leaf streak in rice

Abstract

Rice bacterial leaf streak (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) significantly reduces rice yield and quality. Traditional chemical control methods often have limited efficacy and raise environmental concerns, highlighting the need for safer and more effective alternatives. This study is the first to comprehensively investigated the antibacterial properties of zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs) against Xoc. The ZIF-8 NPs showed strong in vitro bactericidal effects with a half-maximal inhibitory concentration (EC₅₀) of 0.15 mg/mL. The antibacterial mechanism of ZIF-8 NPs involves disrupting bacterial membrane integrity, inducing DNA damage, and triggering an excessive burst of reactive oxygen species, leading to oxidative stress and cell death. Compared to conventional pesticide formulations, ZIF-8 NPs demonstrated superior efficacy in suppressing Xoc growth. In addition, ZIF-8 NPs significantly suppressed the activities of multiple virulence factors of Xoc including extracellular hydrolase (protease, cellulase, and pectinase), extracellular polysaccharide production, and biofilm formation, and showed effective adhesion and bidirectional transport in rice tissues. Greenhouse experiments also revealed that the NPs enhanced the antioxidant activity of some key enzymes in rice, reducing disease severity, while ensuring the biosafety of non-targeted organisms. These findings underline the potential of ZIF-8 NPs as a promising nano-antimicrobial agent for sustainable BLS management, offering an environmentally friendly alternative to conventional pesticides in rice disease control.