Differential Analysis of Three Copper-Based Nanomaterials with Different Morphologies to Suppress Alternaria alternata and Safety Evaluation.

The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH) 2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu 2 O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu 2 O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata . Its EC 50 were 104.24 and 89.40 mg L -1 , respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu 2 O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies.