Influence of root inducers and substrates on the vegetative propagation of pitahaya species (Hylocereus spp.) under nursery conditions

Abstract

Pitahaya (Hylocereus spp.) is an emerging crop for tropical regions; however, its vegetative propagation is strongly influenced by environmental and management factors. Optimizing rooting and establishment under nursery conditions is essential to produce uniform and vigorous seedlings. This study evaluated the effects of root inducers and substrates on the vegetative propagation of three Hylocereus species under nursery conditions. A completely randomized design (CRD) with a 2×2×3 factorial arrangement was implemented, including two root inducers (NAA + IBA solution and seaweed extract), two substrates (substrate 1 and substrate 2), and three species (H. undatus, H. megalanthus, and H. costaricensis), resulting in 12 treatments with four replicates each. Seven variables were assessed: shoot emission time (SET), cutting viability (CV), number of shoots (NS), shoot length (SL), number of roots (NR), root length (RL), and vegetative vigor index (VVI). ANOVA revealed significant effects (p ≤ 0.05) in the three-factor interaction for SET, CV, NS, SL, RL, and VVI. Treatment T9 achieved the shortest SET (21.53 days) and highest CV (100%), T7 recorded the highest NS (1.62 shoots plant⁻¹), T3 showed greater SL (68.67 cm) and NR (5.30 roots plant⁻¹), and T12 obtained the highest RL (42.69 cm) and VVI (110.18). Effect size analysis based on partial eta squared (ηp²) identified species as the most influential factor, explaining 55–98% of the observed variance. Among the evaluated species, H. costaricensis showed the best overall performance. These findings demonstrate that combining H. costaricensis, substrate 1, and NAA + IBA enhances vegetative propagation efficiency. These findings provide valuable evidence for improving pitahaya propagation protocols and optimizing seedling production under nursery conditions.