*2.2. Magnesium Fertilization Forms Treatment Protocol*

The foliar magnesium application was laid out as control (0.5 g L−<sup>1</sup> ), MgSO4·7H2O (0.5 g L−<sup>1</sup> ), Mg-EDTA (Mg chelate 0.5 g L−<sup>1</sup> ), and Mg-NPs powder (0.5 g L−<sup>1</sup> ). Nanomaterials provided magnesium nanoparticles (MgO, 99%+ purity, 20 nm) in powder form at sundown. This optimal concentration was used for application. At sundown during the four stages of growth (flowers, fruit set, veraison, and harvest), foliar treatments were made (7:00 pm). In a bath of warm tap water, the magnesium compounds were melted. Using a knack-sap pump, the solutions were sprayed over the entire vine monthly until the leaves became saturated. The rest of the magnesium salts were acquired from EL-Gomhoria Co. Ltd. in Egypt from EL-Gomhoria Co. Ltd. In Mansoura city, Egypt.
