Effects of green synthesized zinc and copper nano-fertilizers on the morphological and biochemical attributes of basil plant

In the present study, the green synthesis of Zn and Cu nanoparticles (NPs) was carried out via Zn and Cu ions reduction during their exposure to basil extract. The shape, size and chemical identity of the Zn and Cu NPs were determined using SEM and XRD analysis. To investigate the effects of the Zn and Cu NPs on the morphological and biochemical traits of basil plant, an experiment was conducted as a factorial based on completely randomized design with 4 levels of Zn NPs (0, 1000, 2000, and 4000 ppm) and 4 levels of Cu NPs (0, 1000, 2000, and 4000 ppm). Based on the results, nutrient treatments, especially 4000 ppm Zn NPs + 2000 ppm Cu NPs caused a significant increase in most morphological parameters. The application of the Zn and Cu NPs significantly affected concentrations of chlorophyll a, chlorophyll b, total chlorophyll and carotenoid in the leaves of basil plants. The highest total phenolic and flavonoid content was obtained for 4000 ppm Zn NPs + 2000 ppm Cu NPs treatment. Plants treated with 4000 ppm Zn NPs + 0 ppm Cu NPs showed the highest antioxidant activity followed by 4000 ppm Zn NPs + 2000 ppm Cu NPs and 2000 ppm Zn NPs + 0 ppm Cu NPs. It can be concluded that foliar application of the Zn and Cu NPs is necessary for obtaining better quantity and quality in basil.