The objective of this study was to evaluate the effect of the foliar application of hydrogen peroxide (H2O2) in mitigating the effects of salt stress on cherry tomato cultivation in a hydroponic system. The experiment was conducted in a greenhouse, using a Nutrient Film Technique hydroponic system. The experimental design used was completely randomized in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution—ECns (2.1, 2.8, 3.5, and 4.2 dS m−1), considered as plots, and five H2O2 concentrations (0, 12, 24, 36, and 48 µM), regarded as subplots, with four replicates and two plants per plot. An increase in the electrical conductivity of the nutrient solution negatively affected the production components of cherry tomatoes. However, it did not affect the post-harvest quality of the fruits. Despite the reductions observed in the production components due to the increase in the electrical conductivity of the nutrient solution, foliar application of H2O2 at concentrations esteemed between 22 and 25 µM attenuated the deleterious effects of salt stress on the number of fruits and ascorbic acid content and increased the total fruit production per plant of cherry tomatoes.
