Control of Fusarium wilt disease of tomato and improvement of some growth factors through green synthesized zinc oxide nanoparticles

Abstract

Metabolites from biomass of Trichoderma harzianum were used for green synthesis of zinc oxide nanoparticles (ZnONPs) from zinc nitrate (ZnNO3) and GC/MS analysis of metabolite was performed. Then, the antifungal activity of synthesized ZnONPs was evaluated against Fusarium oxysporum under the laboratory and greenhouse conditions. Results were compared to different concentrations of Iprodione + Carbendazim (Rovral-TS®) fungicide. Synthesized ZnONPs were characterized by ultraviolet-visible spectrometry (UV-Vis), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR). UV-Vis spectra showed an intense peak at 339 nm. X-ray diffraction pattern showed the crystalline nature and purity of the ZnONPs. FTIR revealed various functional groups including phenols, ketones, aldehydes, aliphatic and primary amines, nitriles, alkanes and alkynes in synthesized ZnONPs. Size of ZnONPs determined in the range from 25–60 nm. Based on atomic absorption spectroscopy, foliar application of synthesized ZnONPs, led to considerable accumulation of zinc in the leaves and suitable for compensate zinc deficiency. Some growth factors including root length, root volume, stem length, stem diameter and number of leaves improved in the treatments containing metabolite of T. harzianum, ZnNO3 and ZnONPs. Complete inhibition of mycelia growth of F. oxysporum was observed in 100 µg/ml concentration of ZnONPs in the laboratory conditions and disease percentage significantly reduced in the greenhouse conditions, indicated that green synthesized ZnONPs gave better results in low concentration than the fungicide. Therefore, application of green synthesized ZnONPs could be recommended as effective alternative and eco-friendly method for crop protection instead chemical fungicides.