Dual-Functional Magnesium-Doped Zeolitic Imidazolate Framework-8 Nanoparticles for Rice Blast Control and Restoration of Magnesium-Deficient Photosynthesis.

Abstract

Conventional chemical control of rice blast often leads to increased pathogen resistance and environmental challenges. Therefore, developing efficient and eco-friendly alternatives has become a key focus in rice blast management. In this study, magnesium-doped zeolitic imidazolate framework-8 nanoparticles (Mg-ZIF-8 NPs) were developed to deliver multiple agronomic benefits, including potent antimicrobial activity, enhanced photosynthetic efficiency and improved plant immunity. The Mg-ZIF-8 NPs, with an average size of approximately 314.50 nm, induced reactive oxygen species production in <i>Magnaporthe oryzae</i>, disrupted membrane permeability, increased lactate dehydrogenase activity, altered cell surface ζ potential, and caused oxidative damage to cellular structures. Specifically, treatment with Mg-ZIF-8 NPs disrupted filamentous mitochondrial biogenesis in <i>M. oryzae</i>, impairing energy metabolism and ultimately reducing fungal virulence by restricting the development of infectious structures. Notably, we found that <i>M. oryzae</i> infection triggers a significant decline in leaf magnesium content, a key factor contributing to subsequent photosynthetic inhibition. Application of Mg-ZIF-8 NPs directly addresses this vulnerability by replenishing magnesium, effectively restoring photosynthetic function and suppressing rice blast development. Additionally, under magnesium-deficient conditions, Mg-ZIF-8 NPs serve as an effective supplement that promotes photosynthetic efficiency, activates MAPK signaling pathways and elevates the expression of defense-related genes. In addition to their ability to enter rice cells through stomata and the subsequent transport of magnesium within the plant, Mg-ZIF-8 NPs demonstrated high biosafety across a range of nontarget organisms. Overall, this study offers a promising strategy for simultaneously controlling rice blast and improving rice physiological performance.