Synergistic Antifungal Activity of Green Synthesized Silver Nanoparticles and Epoxiconazole against Setosphaeria turcica

Abstract

It is urgent to develop highly efficient and eco-friendly antimicrobial agents for integrated control of phytopathogens. Silver nanoparticles (AgNPs) were synthesized by Ligustrum lucidum leaf extract. UV-vis spectrum showed that there was a strong absorbance at 438 nm. Transmission electron microscopy (TEM) images displayed that synthesized nanoparticles were near spherical with an average size of 13 nm. The antimicrobial effect of AgNPs was evaluated through methods of paper disk diffusion, colony growth, conidia germination, and in vitro inoculation. The 50% inhibition concentration (IC50) of AgNPs against Setosphaeria turcica was 170.20 μg/mL calculated by SPSS 13.0. In addition, it displayed a significant synergistic antifungal effect when AgNPs were combined with epoxiconazole at the ratios of 8 : 2 and 9 : 1. The results of this study provide a novel fungistat not only for comprehensive control of plant fungi but also for reducing chemical pesticides use and avoiding drug-resistant phytopathogen generation.