Silver oxide nanostructures as a new trend to control strawberry charcoal rot induced by Macrophomina phaseolina

Silver oxide (Ag₂ O) nanostructures were fabricated and their ability to induce antifungal activity against Macrophomina phaseolina, which causes charcoal rot disease in strawberries, was evaluated under laboratory, greenhouse and field conditions. A real-time quantitative polymerase chain reaction was used to monitor expression of defense-related genes, which is essential to evaluate the potential of the manufactured nanoparticles to promote strawberry resistance against charcoal rot. The effect of Ag₂ O nanoparticles on growth characteristics in strawberry plants was also studied.

The results showed that Ag₂ O significantly inhibited M. phaseolina growth compared with untreated controls under in vitro conditions. Strawberry plants treated with Ag₂ O showed a significant decrease in the severity of charcoal rot disease in the greenhouse compared with untreated plants. Strawberry plants treated with Ag₂ O nanoparticles expressed defense gene (PR-1) involved in the salicylic acid signaling pathways at levels three to five times higher than in the control group. Ag₂ O nanoparticles significantly improved the growth and yield of the strawberry crop.

Use of Ag₂ O nanoparticles can be considered a new strategy to control M. phaseolina and this is the first report of this effect. © 2022 Society of Chemical Industry.