Assessment of mycogenic zinc nano-fungicides against pathogenic early blight (Alternaria solani) of potato (Solanum tuberosum L.)

Abstract

The present investigation was carried out to evaluate the efficacy of mycogenic zinc oxide nanoparticles (ZNONPs) as antifungal agents against Alternaria solani (early blight of potato). The nanoparticles were synthesized biologically by using Aspergillus niger biomass and characterization was done by UV–Vis Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-Ray (EDX), Dynamic Light Scattering (DLS), Fourier Transform Infra Red (FTIR), Atomic Force Microscopy (AFM) and inductively coupled plasma mass spectrometry (ICPMS). The UV–Vis spectroscopy showed peaks between the range 250 nm to 340 nm, corresponding to ZNONPs. The FESEM results also confirmed the synthesis of fine sized and spherical ZNONPs. EDX analysis result showed the optical absorption peak corresponding to ZNONPs. The DLS result confirmed the synthesis of ZNONPs with average size of 96.43 nm. FTIR analysis depicted information about all the chemical interactions of ZNONPs. AFM image depicted the three dimensional conformations of ZNONPs. The ZNONPs were tested against A. solani in vitro and minimum inhibitory concentration (MIC) was calculated. Field experiment was conducted for comparison of the efficacy of nanoparticles and chemical fungicide at the parameters of disease severity, tuber number and tuber weight. The data were analyzed by SPSS for analysis of variance (ANOVA) with least significance difference (LSD) and results were found to be significant for different parameters at 0.05 significance levels. It may be concluded by the experiment that ZNONPs may be proved to be potential fungicides in near future and it is an excellent alternative to chemical fungicides.