Impact of Zn Nanoparticles Synthesized via Green and Chemical Approach on Okra (Abelmoschus esculentus L.) Growth under Salt Stress

Abstract

The study investigated the green and chemical approaches for the preparation of Zn nanoparticles and their effect on the growth of okra plants under saline conditions. The leaf extract of Sorghum bicolor L. was used for the green synthesis of zinc nanoparticles (Zn-GNPs). Zinc nanoparticles (Zn-NPs) were also produced by the co-precipitation method (Zn-CNPs). The synthesized NPs were characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) and were applied foliarly in the range of 0.1%, 0.2%, 0.3% on okra plants. A marked increase in the shoot and root fresh and dry weight (g) and chlorophyll contents were observed under normal and saline conditions. An increase in antioxidant activity was observed under saline conditions. However, the foliar application of 0.3% Zn-GNPs was helpful in the regulation of the antioxidant defense system under a saline environment. Based on the results, it can be concluded that the use of Zn-GNPs is the most promising eco-friendly approach in mitigating salinity stress.