Use of magnesium nanomaterials in plants and crop pathogens

Synthesis and application of metal nanomaterials (NMs), particularly nanoparticles (NPs), have significantly increased in agriculture and biotechnology, various fields of medicine, energy, and material sciences. NMs synthesized from essential metals required by organisms are among the most preferred ones thanks to their unique physicochemical properties that make them suitable for agricultural and biotechnological applications. Magnesium (Mg) is an essential metal for organisms; however, NMs of this element have been little studied compared to those of zinc, iron, and copper, among others. This review thoroughly examines the use of Mg-based NMs (Mg-NMs) during the last decade. It compiles their physiological effects on plants and crop pathogens and addresses their impact according to intrinsic aspects of NMs, as well as plant immune responses. Spherical Mg-NMs are the most commonly studied in plant and crop pathogens. The sizes and concentrations of Mg-NMs range from 3.5 to 2000 nm and 0.15 to 20,000 ppm, respectively. In general, Mg-NMs appear to promote plant growth and systemic stimulation against pathogens with a few reports associated with high phytotoxicity, increase production of secondary metabolites, enhance phytoaccumulation/decontamination of heavy metals, improve postharvest flower quality, and have demonstrated antimicrobial activity for various crop pathogens. This document seeks to provide valuable insights into the current understanding and future research perspectives of Mg-NMs for their use in plants, phytopathogen control, and agricultural practices.