The Effect of Paclobutrazol Applications on Yield, Quality, Plant Growth and Residue in Hydroponic Tomato Cultivation

The study was conducted in 2022 in a fully automated, soilless agriculture greenhouse at the Research Centre Directorate of Tokat Gaziosmanpaşa University. The study investigated the effects of different doses of paclobutrazol (PBZ) on yield, quality, plant growth, and PBZ residue levels in tomato plants. The plant material employed in this study was the Belford Fı (Syngenta-Türkiye) pole tomato variety. The experiment was conducted in three replicates according to a random plots factorial experiment design. The results of this study indicate that foliar applications of 50 ppm, and 100 ppm PBZ produced the most optimal outcomes. The highest marketable yield was observed in the treatment with a foliar application of 50 ppm PBZ, resulting in an average yield of 385.33 kg/ha. Subsequently, a foliar application of PBZ at a rate of 100 ppm (374.24 kg/ha) was conducted, along with a control treatment (268.55 kg/ha). The study revealed no statistically significant differences between treatments in terms of fruit wet weight, dry weight, pH, and titratable acidity. Furthermore, as the PBZ doses increased, the internode length, and plant height showed a corresponding reduction. The findings of this study indicate that, in soilless tomato cultivation, foliar applications of PBZ produce superior results compared to soil applications. Additionally, no PBZ residue was detected in the fruit.