Effect of naphthalene acetic acid (NAA) on dragon fruit (Hylocereus undatus) cuttings under different growing conditions

The experiment, conducted during 2023-2024 at the Department of Horticulture, North-Eastern University, Tura Campus, West Garo Hills, Meghalaya, evaluated the effects of Naphthalene Acetic Acid (NAA) concentrations and growing conditions on dragon fruit (Hylocereus undatus) cuttings. A Factorial Randomized Block Design (FRBD) with three replications tested two factors: NAA concentrations (0, 100, 150, 200 ppm) and growing conditions (greenhouse, polyhouse, open conditions). The combination of polyhouse conditions with 200 ppm NAA recorded the highest values for number of roots per plant (20.18), root length (17.95 cm), plant height (23.51 cm), fresh weight of shoots (43.94 g), dry weight of shoots (11.29 g), fresh weight of roots (4.81 g), dry weight of roots (1.09 g), survival rate (92.59%), number of sprouts per plant (2.66), length of sprouts (21.98 cm), and girth of sprouts (26.66 mm). Untreated cuttings in greenhouse conditions exhibited the lowest performance across all parameters. Additional parameters, including root-to-shoot ratio, chlorophyll content, and days to first sprout, further supported the efficacy of the polyhouse-NAA combination. These findings highlight optimal conditions for dragon fruit propagation in subtropical regions.