MgO Nanoparticles Biosynthesis and Its Effect on Chlorophyll Contents in the Leaves of Clusterbean (Cyamopsis tetragonoloba L.)

Abstract

Fungus mediated biological synthesis of MgO nanoparticle is a new approach for environmentally benign protocol in context to green nanotechnology. The fungal isolate was identified on the basis of morphological and molecular parameters. Transmission electron microscope (TEM), Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM) was used for size and shape study. To ensure the elemental proportion, electron dispersive spectroscopy (EDS) was performed. Hydrodynamic diameter and zeta potential of MgO nanoparticles were calculated using dynamic light scattering (DLS). The crystal nature was confirmed by high resolution transmissionelectron microscope (HR-TEM), selective area electron diffraction (SAED) and X-ray Diffraction (XRD) patterns, In addition bonding patterns of the synthesized nanoparticles were examined by Fourier Transform Infrared Spectroscopy (FTIR). Investigation was made to study the effect of biosyntheiszed nanoparticle on chlorophyll contents in the leaves of Clusterbean (Cyamopsis tetragonoloba L.). Aspergillus flavus, strain TFR-12 having potential to synthesize MgO nanoparticles with average hydrodynamic diameter of 5.8 nm, polydispersity Index 0.289, Zeta potential −6 66 mV and random in shape which are stable up to 90 days, These biologically synthesized nanoparticles were found suitable for plant nutrition more particularly to clusterbean (Cyamopsis tetragonoloba) that demonstrate greater improvement in shoot-root growth (18.2 to 49.2%) and chlorophyll photosynthetic pigment (76.1%) by the application of biologically synthesized MgO nanoparticle at 15 Mg L−1 concentration on two week old plants. The present invention of nanoparticle biosynthesis is a low cost green, ecofriendly approach, capable to producing monodisperse MgO nanoparticles using the fungus Aspergillus flavus, strain TFR-12. These biologically synthesized nanoparticles were found suitable for plant nutrition more particularly to clusterbean (Cyamopsis tetragonoloba) but not limited that enhance chlorophyll contents in the leaves which may further help in enhancement of light absorption by plants for photosynthesis process.