Kanthi Pangestuning Prapti, Setyono Yudo Tyasmoro, Moch Dawam Maghfoer, Nurul Aini
This study aims to evaluate the effect of gibberellin (GA3) on the regulation of flowering and fruit development of red dragon fruit (Hylocereus polyrhizus) during the off-season period. The research was conducted in Banyuwangi, Indonesia, using a single-factor Randomized Block Design (RBD) consisting of five GA3 concentrations: 0, 200, 400, 600, and 800 ppm. The observed parameters included the time to first flowering, number of flowers, number of fruits, fruit weight, fruit volume, peel thickness, sugar content (°Brix), and anthocyanin content. Analysis of variance showed that GA3 application had a highly significant effect (p < 0.01) on flowering time, flower and fruit number, fruit weight, and fruit volume, but did not significantly influence peel thickness or sugar content. Concentrations of 400–600 ppm produced the most favorable physiological responses, accelerating flowering time, increasing flower and fruit numbers by up to twofold compared with the control, and significantly enhancing fruit weight and volume. A negative correlation between GA3 concentration and flowering time (r = –0.81*) indicated accelerated generative transition, while a positive correlation between GA3 and yield (r = 0.92*) confirmed improved reproductive efficiency. These mechanisms are theoretical explanations based on existing models and literature, rather than direct measurements of gene expression or protein activity in this study. These findings demonstrate that GA3 application at 400–600 ppm can serve as an effective agronomic strategy to extend the production period, increase yield, and maintain fruit quality of red dragon fruit under tropical off-season conditions. © (2026), (Polskie Towarzystwo Inzynierii Ekologicznej (PTIE)). All rights reserved.
Faculty of Agriculture, Universitas Brawijaya, East Java, Malang, Indonesia; Agrotechnology Program, Faculty of Agriculture & Fisheries, Universitas 17 Agustus 1945 Banyuwangi, East Java, Indonesia; Department of Agronomy, Faculty of Agriculture, Universitas Brawijaya, East Java, Malang, Indonesia
