Magnesium (Mg) is the structural component of chlorophyll and polysaccharides and also an activator of several enzymes. Magnesium plays an important role in photosynthesis. An attempt was made in the present investigation on utilizing this property for increasing rate of photosynthesis of maize plant and subsequently higher root exudations which enhance the microbial activities in soil. Green house experiments were conducted to evaluate the effect of MgO nano particles spray on maize plant (Zea mays L.) in three benchmark soils of India which are phosphorus (P) deficient. Results revealed that application of MgO nano particles spray 10 mg/L (viz. 15, 28, and 35 days after sowing) enhanced the enzymatic activities like phytase and phosphatase particularly in roots of P deficient plant. | Magnesium oxide nano particles effects on utilization of soil phosphorus by maize (Zea mays L.) plant