Phytofabricated zinc oxide nanoparticles as a nanofungicide for management of Alternaria blight of Brassica

Abstract

Plant pathogens resistant to the commercially available fungicides and bactericides even at higher concentrations are the biggest challenge for the farmers to control the losses due to plant diseases. The antibacterial and antifungal potential of nanomaterials makes them a suitable candidate for the control of plant diseases. Thus, the present study reports the phytofabricated zinc oxide nanoparticles (ZnO Np's) using aqueous plant leaf extract of Terminalia bellerica (Baheda). Characterization of ZnO nanoparticles was done by ultraviolet-visible (UV-Vis) studies, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FT-IR) analysis, and transmission electron microscopy (TEM). The presence of pure hexagonal wurtzite crystalline structure of ZnO nanoparticles was confirmed by XRD analysis. The TEM images revealed the spherical to hexagonal shaped ZnO nanoparticles with sizes ranging from 20 to 30 nm. The stabilization of synthesized ZnO nanoparticles through the interactions of terpenoids, steroids, phenylpropanoids, flavonoids, phenolic acids, and enzymes present in the leaf extract was suggested by FTIR analysis. The mechanism of the formation of ZnO nanoparticles using Terminalia bellerica (Baheda) (Tb-ZnO Np's) as a bioactive compound is proposed. These phytofabricated ZnO nanoparticles (Tb-ZnO Np's) have shown significant antifungal potential against Alternaria brassicae the causal agent of Alternaria blight disease/leaf spot disease in Brassica species. The microscopic results confirm the changes in mycelium morphology and reduction in the number of spore germination at 0.2 mg/mL concentration Tb-ZnO Np's.

Biocontrol potential of mycogenic copper oxide nanoparticles against Alternaria brassicae

“…After treatment with M-CuO NPs, the maximum detrimental effects were detected at 200 ppm, which substantially lowered spore counts and caused the hyphal wall to lose its integrity ( Figure 10F ). Similar observations were reported by Dhiman et al (2021) . In their study, a comparative study of biologically and chemically synthesized zinc oxide nanoparticles was done, which have reduced the average dimensions of conidia length and conidia width of A. brassicae infecting brassica species.…”

Nanobiopesticides in sustainable agriculture: developments, challenges, and perspectives

“…In addition, ZnO-based and phytofabricated ZnO NPs have also been reported as nanofungicides to manage plant pathogens. 88,143 All these studies suggest that the biosynthesis of nanobiofungicides is cheaper and more environmentally sustainable and stable than using chemical synthesis methods. Chitin/chitosan-based stimulus responsive nanopreparations can release active nanopesticides more accurately and effectively and adopt targeted delivery or controlled-release mechanism.…”

Mechanistic Insight of the Antifungal Potential of Green Synthesized Zinc Oxide Nanoparticles against Alternaria brassicae

“…Microscopic studies also confirmed the absence of spores and deformed fungal hyphae posttreatment. The detailed experiments and results of this study have been already reported in our previous study which is shown in Figure 1 [18].…”

“…Synthesized Tb-ZnO NPs have shown significant antifungal potential at 200 ppm as compared to commercially available chemical fungicides and chemically synthesized ZnO NPs . The changes in fungal hyphae morphology and reduction in spore germination were reported by microscopic studies [18]. To get more insight into the mechanism of action of nanoparticles against the fungal cell, the present work has been done to study the mechanistic approach of Tb-ZnO NPs against A. brassicae by analysing the cytomorphological, biochemical constituent and stress enzyme.…”

“…The antifungal property of ZnO nanoparticles synthesized from aqueous plant leaf extract of Terminalia bellerica (Tb-ZnO) was determined by poisoned food technique and microscopic studies of hyphae and spores. All experimental details related to synthesis process have been given in previous study [18].…”