Effects of Gibberellic Acid (GA₃) on Fruit Size and Flesh Coloration in Bicolored Pitaya (Hylocereus sp.)

Bicolored pitaya exhibits variable flesh coloration that directly affects fruit quality and market value. This study evaluated the effects of exogenous gibberellic acid (GA₃) on fruit growth, total soluble solids (TSS), and fruit coloration under field conditions. GA₃ application increased fruit weight, fruit size, and peel thickness, indicating enhanced fruit enlargement. Colorimetric measurements (L*, a*, b*) and visual assessment showed that GA 3 treated fruits exhibited lighter and less uniform coloration in both peel and flesh, particularly at higher concentrations and later application stages. The effects of GA₃ on TSS were variable and not consistently significant across treatments. These findings suggest a trade-off between fruit enlargement and visible coloration following GA₃ application.