Synthesis and in vitro antifungal efficiency of alginate‐stabilized Cu 2 O‐Cu nanoparticles against Neoscytalidium dimidiatum causing brown spot disease on dragon fruit plants ( Hylocereus undatus )

Cu 2 O‐Cu nanoparticles (Cu 2 O‐Cu NPs) stabilized by alginate have been developed for using as a plant fungicide. The antifungal effect of Cu 2 O‐Cu NPs against Neoscytalidium dimidiatum fungus causing brown spot disease in dragon fruit plants was investigated. Transmission electron microscopy (TEM) was used to assess the morphology and size of Cu 2 O‐CuNPs. The average diameter of spherical Cu 2 O‐Cu NPswas determined to be 5.4 ± 0.4 nm. Furthermore, the Cu 2 O‐CuNPs stabilized in alginate were also characterized by Fourier transform infrared (FT‐IR) and X‐ray diffraction (XRD) analysis. Especially, the prepared Cu 2 O‐Cu NPs/alginate showed high antifungal efficiency (~100 %) against Neoscytalidium dimidiatum with 30 ppm concentration copper. The obtained results showed that Cu 2 O‐Cu NPs stabilized in alginate have great potential in the development of nanomaterials for plant fungicide applications.