Graphene Oxide-Silver Nanocomposite: Novel Agricultural Antifungal Agent against Fusarium graminearum for Crop Disease Prevention

Nanoparticle-based antibacterial agents have emerged as an interdisciplinary field involving medicine, material science, biology, and chemistry because of their size-dependent qualities, high surface-to-volume ratio, and unique physiochemical properties. Some of them have shown great promise for their application in plant protection and nutrition. Here, GO-AgNPs nanocomposite was fabricated through interfacial electrostatic self assembly and its antifungal activity against phytopathogen Fusarium graminearum was investigated in vitro and in vivo-foe the first time. The results demonstrated that the:GO-AgNPs nanocomposite showed almost a 3- and 7-fold increase of inhibition efficiency over pure AgNPs, add GO suspension, respectively. The spore germination inhibition was stimulated by relatively low concentration of 4.68 mu g/mL (minimum inhibition-concentration (MIC)). The spores and hyphae were damaged, which might be caused by an antibacterial: mechanism from the remarkable synergistic effect of GO-AgNPs, inducing physical injury and chemical reactive oxygen species generation. More importantly, the,chemical. eduction of GO mediated by fungal spores was possibly contributed to the high antimicrobial activity Of GO-AgNPs. Furthermore, the GO-AgNPs nanocomposite showed a significant effect in controlling the leaf spot disease infected by F. graminearum in the detached leaf experiment. All the results from this research suggest that the GO-AgNPs nanocomposite developed in this work has the potential as a promising material for the development of novel antimicrobial agents against pathogenic fungi or bacteria.