Protective Role of Mycosynthesized Bimetallic ZnO-CuO Nanoparticles as Therapeutic Nutrients to Enhance the Resistance of Vicia faba against Fusarium Wilt Disease

The exacerbation of climatic changes helped to increase the risk of plant diseases in the world. The novelty of this study lies in the manufacture of therapeutic nutrients using nanotechnology with strong effectiveness against plant disease. Based on this concept, we mycosynthesized bimetallic ZnO-CuO nanoparticles (NPs), alternatives to reduce the spread of Vicia faba Fusarium wilt disease, which is one of the world's most imperative cultivated crops. The article's uniqueness comes in the utilization of ZnO-CuO nanoparticles to carry out two crucial tasks: therapeutic nutrients and managing Fusarium disease. To evaluate the resistance of infected plants, disease index (DI), photosynthetic pigments, osmolytes, oxidative stress and yield parameters were assessed. NPs of ZnO, CuO, and ZnO-CuO were mycosynthesized using a biomass filtrate of Aspergillus fumigatus OQ519856. DI reached 87.5%, due to Fusarium infection, and, as a result, a severe decrease in growth characters, photosynthetic pigments, total soluble carbohydrates, and proteins as well as yield parameters was observed. Infected plants produced more of the studied metabolites and antioxidants. On the other hand, the treatment with CuO-ZnO NPs led to a great decline in the DI by 22.5% and increased the protection by 74.28%. A clear improvement in growth characters, photosynthetic pigments and a high content of carbohydrates and proteins was also observed in both healthy and infected plants as a result of CuO-ZnO NPs treatment. Remarkably, CuO-ZnO NPs significantly increased the yield parameters, i.e., pods/plant and pod weight, by 146.1% and 228.8%, respectively. It could be suggested that foliar application of NPs of ZnO, CuO, and ZnO-CuO could be commercially used as antifusarial agents and strong elicitors of induced systemic resistance.