Evaluation of Fungal Sensitivity to Biosynthesized Copper-Oxide Nanoparticles (CuONPs) in Grapevine Tissues and Fruits.

Grape production is one of the most agronomically important activities worldwide. However, it is threatened by diseases caused by phytopathogenic microorganisms, which cause severe economic losses. The primary strategy to control phytopathogenic fungi is the application of fungicides; however, they affect the environment and induce resistance in fungi. Nanomaterials, especially those green-synthesized, emerge as an eco-friendly and sustainable alternative to control fungal pathogens. The objective of this work is to evaluate the sensitivity of fungal phytopathogens to biosynthesized copper-oxide nanoparticles (CuONPs). Nanoparticles were evaluated as preventive and corrective treatments in grapevine green tissues and fruits under field conditions, using in vitro and in vivo experimental approaches. Interestingly, corrective treatment was highly effective and showed little accumulation of Cu on the fruits, even less than a commercial copper-based fungicide. Moreover, we report that Aspergillus niger causes lesions in photosynthetic tissues and severe disease symptoms in grapes. We also describe for the first time the presence of Alternaria alternata causing lesions, mainly on the stems and young leaves of grapevine plants in Mexico. These pathogens were inhibited by the biosynthesized CuONPs. All these findings show the effectiveness of using CuONPs to control phytopathogenic fungi, even under field conditions, shedding light on their potential use in agriculture with a less environmental impact than the commercial fungicides and agrochemicals currently used.