Biosynthesis of ZnO Nanostructures Using Azadirachta indica Leaf Extract and Their Effect on Seed Germination and Seedling Growth of Tomato: An Eco-Friendly Approach

Abstract

In this study, we report synthesis of Zinc oxide nanoparticles using simple chemical and green methods. The ZnO nanoparticles were synthesized using leaf extract of Azadirachta indica (neem) as reducing agent. The as obtained product was characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray analysis (EDAX) and TEM techniques. XRD analysis confirms that ZnO nanoparticles were crystalline having hexagonal Wurtzite structure with (1 0 0), (0 0 2), (1 0 1), (1 0 2), (1 1 0) and (1 1 2) planes. SEM analyses show that the as synthesized ZnO NPs were in the form of agglomerates and no other impurity peak was found in the EDS. TEM analyses confirm that the size of the nanoparticle was approx. 50 nm. Here in, we investigate the effect of chemical and green synthesized zinc oxide nanoparticles on germination and growth of lycopersicum esculentus (tomato) using petri plate seed germination method in loamy sand soil. The impact of concentration of applied ZnO nanoparticles via green synthesis and chemical methods were analyzed. Results revealed that green synthesized Zinc oxide nanoparticles showed maximum growth of seedling as compared to chemically synthesized Zinc oxide nanoparticles, bulk ZnO and control. After 50 days of tomato growth analysis, it was recognized that ZnO NPs can be a good green synthetic fertilizer by increasing shoot length, wet weight, dry weight and yield over conventional control. Hence, green method is found to be more effective.