PITAYA FLOWERING IN THE CERRADO WITH THE APPLICATION OF GROWTH REGULATORS AT THE END OF THE OFF-SEASON

Abstract

Pitaya cultivation has expanded in Brazil primarily due to the nutritional value of its fruits and the expected expansion of cultivated areas. However, the crop's fruiting seasonality limits fruit supply between May and November in the Brazilian Midwest. In an attempt to overcome this seasonality, the effects of applying gibberellic acid (GA₃) and paclobutrazol at the end of the off-season were evaluated, aiming to accelerate floral induction and fruiting of pitaya, as well as to understand the role of gibberellin in pitaya fruiting. The experiment was conducted in a commercial orchard, with plants 19 months old after planting. The design was a randomized complete block design, with six treatments, four replicates, and five plants per plot. Treatments consisted of applications of 0, 75, 150, 300, and 600 mg L⁻¹ of GA₃, in addition to a treatment with 100 mg L⁻¹ of paclobutrazol, on September 7, 2023. The pitaya showed sensitivity to the application of the substances. Paclobutrazol completely inhibited fruit set, even under inductive environmental conditions, highlighting the crucial role of gibberellin in pitaya fruit set. The different doses of GA₃ provided different responses in flowering and fruit set peaks. Regardless of the GA₃ doses applied, earlier flowering was observed compared to plants in the orchard that did not receive the GA₃ treatment and in neighboring growers. No statistical differences in early flowering were observed between the GA₃ doses. The earlier fruiting period provided by GA3 application at the end of the off-season highlights the potential of GA₃ application as a tool to expand the production window. However, it is necessary to adjust the dose, timing, and application method to maximize treatment effectiveness.

DOI: 10.56238/edimpacto2025.051-011