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

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 Magnaporthe oryzae, 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 M. oryzae, impairing energy metabolism and ultimately reducing fungal virulence by restricting the development of infectious structures. Notably, we found that M. oryzae 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.