Optimizing Foliar Application of Moringa oleifera Leaf Extract for Tomato Yield and Fruit Quality under Mediterranean Greenhouse Conditions

This study aimed to determine the optimum foliar application dose of Moringa oleifera leaf extract (MLE) for tomato production in an uncooled greenhouse under Mediterranean spring–summer conditions. The Alkış F1 oval cocktail tomato cultivar was treated with 0 (control), 1%, 3%, or 5% MLE. Yield, fruit morphological traits, colour, physicochemical quality, dry matter, and bioactive compounds were evaluated. MLE applications significantly increased fruit length, width, weight, and yield. The highest yield was obtained with 5% MLE (9,493 g m⁻²), representing a 50.0% increase compared with the control. At the same dose, fruit weight, dry matter, total phenolic content, total flavonoid content, and vitamin C increased by 48.1, 42.0, 52.7, 129.7, and 98.2%, respectively. MLE increased titratable acidity but reduced total soluble solids, whereas fruit pH, electrical conductivity, and b* values were not significantly affected. Higher MLE doses increased L* and decreased a*, indicating dose-dependent changes in fruit color. Hierarchical cluster analysis clearly separated the control from the MLE treatments, while the 3% and 5% treatments exhibited the most similar overall response profiles. Although 5% MLE produced the highest numerical yield, yield did not differ significantly among the MLE treatments; therefore, the optimum dose could not be conclusively determined.