Effects of Nano-Mn₂O₃ on Growth,Development and Physiological Activity of Tomato

摘要

In recent years,nanomaterials have demonstrated significant potential in agricultural applications.Nano-manganese trioxide （nano-Mn₂O₃）,a novel metal oxide,and its derivatives have emerged as a promising manganese fertilizer to improve crop manganese nutrition,with ongoing research exploring its mechanisms in enhancing plant growth and productivity.Studies have also identified nanozyme-like properties in nanomaterials,though whether Mn₂O₃ exhibits superoxide dismutase （SOD）-mimetic activity in plants or can serve as an enzymatic substitute requires further investigation.This study utilized hydroponically cultivated tomato seedlings treated with varying concentrations of nano-Mn₂O₃ to evaluate its effects on growth,physiological activity （including photosynthesis,antioxidant defense system homeostasis and nutrient absorption/transformation） and its potential SOD-like enzymatic functionality within plant tissues to assess agricultural applicability.Key results demonstrated that,compared to the control,nano-Mn₂O₃ treatment significantly enhanced plant height,stem diameter,root length,aboveground fresh weight,and dry biomass,while improving leaf relative water content,chlorophyll levels and photosynthetic efficiency through boosting electron transport in photosystem II and light energy utilization,collectively enhancing stress resistance.The nanoparticles notably modulated the antioxidant defense system by elevating catalase （CAT） and peroxidase （POD） activities,while exhibiting intrinsic SOD-like enzymatic behavior,suggesting their role as nanozyme substitutes.Specifically,0.05 g·L^-1 nano-Mn₂O₃ optimally promoted root development parameters,whereas 0.5 g·L^-1 most effectively enhanced aerial growth metrics.Additionally,all tested concentrations significantly influenced macronutrient accumulation in aboveground tissues,with concentration-dependent effects observed on nutrient assimilation patterns.These findings underscored nano-Mn₂O₃'s dual functionality as both a micronutrient supplement and enzymatic substitute,providing critical insights for developing advanced nano-enabled agricultural inputs.

关键词

Nano-Mn₂O₃ / promoting growth / nanofertilizer / tomato seedling / absorption and transformation