Performance of tomato grown under different water replacement depths and silicon application forms

Water management has a direct impact on plant development, and under deficit conditions, it often results in reduced yields. Silicon (Si), however, has the potential to alleviate stress and enhance plant performance under unfavorable conditions. This study aimed to analyze the performance of tomato plants cultivated under different water replacement depths and forms of silicon application. The experiment was laid out in a completely randomized design with a 2 × 4 factorial arrangement represented by two water replacement depths (60% and 100% of crop evapotranspiration - ETc) and four forms of silicon application (without application, soil application - full dose, soil application - split dose, and foliar applications). Four replications were used. The plants were cultivated in a protected environment using drip irrigation for water replacement, and silicon oxide served as the source of the element. The analyzed parameters included daily evapotranspiration, leaf spectral reflectance, mass accumulation (root, stem, and leaf), yield indices (fruit weight, plant yield, and defective fruits), water productivity, and post-harvest fruit weight loss. The imposition of water deficit (60% of ETc) in tomato leads to reduced crop development and yield, with the effects partially mitigated by the application of silicon. Conversely, under conditions of adequate water replacement (100% of ETc), silicon application contributes to increased development and yield of tomato. The application of silicon in the soil, whether in a full or split dose, demonstrates a more favorable response in vegetative indices and yield for tomato.