Utilizing manganese-based nanoparticles for enhancing environmental stress resilience and productivity of plants

Climate change, coupled with various abiotic and biotic stresses, continues to cause substantial global losses in crop yields, threatening food security. Innovative technologies, such as nanotechnology, have shown potential to address these challenges by improving agricultural productivity and sustainability. Manganese (Mn), an essential micronutrient, plays a crucial role in photosynthesis, nitrogen assimilation, reactive oxygen species (ROS) scavenging, hormone signaling, pathogen defense, structural polymer synthesis, and interactions with plant-associated microbes. As a vital cofactor in the oxygen-evolving complex (OEC) of photosystem II (PSII), Mn catalyzes the water-splitting reaction essential for photosynthesis. Nanoscale Mn based nanoparticles (NPs), including Mn, MnO, Mn₂O₃, MnO₂, Mn₃O₄, MnFe₂O₄, Mn_0.5Zn_0.5Fe₂O₄, biochar-modified MnO₂ (BC@MnO₂), and composite nanomaterials like chitosan/silver/Mn_0.5Mg_0.5Fe₂O₄ (Cs/Ag/MnMgFe₂O₄), offer superior bioavailability, reactivity, and stress mitigation compared to bulk Mn sources or untreated controls. Studies report up to a 45% increase in growth parameters and a 49% increase in yield with Mn NP application compared to untreated plants under field conditions. Additionally, these NPs modulate signaling, regulate stress-related gene expression, and activate defense mechanisms, thereby supporting overall plant health and productivity. Optimizing Mn based NP synthesis, functionalization, and application strategies will be crucial for ensuring safety and maximizing efficacy. Although Mn based NPs hold great potential for sustainable agriculture, their widespread adoption demands thorough research and validation to ensure agricultural benefits while maintaining ecological responsibility.