Mass propagation of pitaya (dragon fruit)

Introduction . To facilitate establishment of pitaya (Hylocereus undatus ) cultivations in new areas, factors affecting its propagation by cuttings and seeds were studied. Materials and methods . Firstly, cuttings of (5, 15 and 25) cm length were tested in three substrates: peat moss (pm), peat moss and sand mix (1:1) (pm/sa) and sand (sa). Indole-3-butyric acid (IBA) solutions were prepared at [0, 5, 10 or 15] mM dissolved in 70% ethanol. After the basal cuttings were dipped for 10 s in these IBA solutions, cuttings were planted in (pm/sa). After (1, 2 or 3) weeks, the cutting rooting, number and length of the developed roots were measured. Moreover, germination was tested at four temperatures [(16, 20, 24 and 28) °C] by placing seeds on wetted filter papers in Petri dishes. Light effect was tested at four white light intensities of (0, 500, 1000 or 2000) lx. Seed viability was tested at 24 °C in darkness with 1000 seeds. The effect of (pm), (pm/sa) and (sa) was tested on germination and seedling growth. The percentage of germination, days to emergence and growth rate of seedlings were measured. Results and discussion . After two weeks, 25-cm pitaya cuttings rooted successfully in the three substrates, but the number and length of the developed roots were affected by the type of substrate. A significant effect of cutting size on root initiation, and number and length of the developed roots was found. IBA consistently improved rooting percentage and root number and length. Overall, 5-cm-long cuttings treated with IBA (10 mM) could be efficient at propagating pitaya. The seed viability was 83%. Germination, which varied between (71 and 83)% depending on the temperature, began after 6 days at (24 and 28) °C. Light intensity at (1000 or 2000) lx reduced seed germination. Potted seedlings grew successfully in the greenhouse.