Control of early blight caused by Alternaria solani using metal oxide nanostructures as direct antifungal agents and resistance inducers in potato plants

BACKGROUND: ) as resistance inducers and antifungal agents against Alternaria solani, which is responsible for early blight in potatoes. The induction of resistance by these nanostructures in potatoes was demonstrated by comparing the expression of defense genes and free amino acid content in treated and untreated plants. However, the direct antifungal activity of these nanostructures was evaluated by assessing their ability to inhibit Alternaria solani growth in vitro and reduce early blight severity in the field. RESULTS: The results revealed that the tested nanostructures demonstrated their high ability to inhibit the growth of Alternaria solani with inhibition percentages reaching 97% and 100% compared to the untreated control. Under field conditions, potato plants treated with the tested nanostructures showed a significant reduction in pathogen severity reaching 60% compared to the untreated control. The results of the stimulatory effect of the tested nanostructures showed a marked increase in the expression of defense and pathogen-associated genes (pathogen-associated protein 1b and 12-oxo-phytodiinoate reductase 3) in the treated compared to untreated plants. Furthermore, potato plants treated with the tested nanostructures exhibited a higher content of free amino acids compared to untreated control. Finally, the tested nanostructures significantly improved potato growth characteristics and yield compared to the untreated control. CONCLUSION: Using these nanostructures may be a new strategy to manage this pathogen in potatoes, but more research should be done on their impact on humans and the environment. © 2026 Society of Chemical Industry.