Selenicereus undatus

Name and natural range

Plants of the World Online accepts Selenicereus undatus (Haw.) D.R.Hunt and treats Hylocereus undatus as a synonym. Its native range extends from Mexico to Honduras. Many other areas are recorded as introduced. Older physiological papers used a broader distribution account, retained here as the context of historical literature. [2-WWW]

Stem, roots and fruit

The segmented stems used in Nobel’s studies had three ribs. Adventitious roots allow segments to root and become units taking up water from the substrate. Typical fruit of the white-fleshed group has red peel and numerous black seeds. Cultivar identification is retained in cultivation because breeding material differs in fruit characters and pollen compatibility. [Nobel 2006, Nobel 2006 p. 469–470, Abirami et al. 2021 p. 2–4, Chu and Chang 2020 p. 2] [Abirami et al. 2021, Nobel 2006 p. 469–470, Abirami et al. 2021 p. 2–4, Chu and Chang 2020 p. 2] [Chu and Chang 2020, Nobel 2006 p. 469–470, Abirami et al. 2021 p. 2–4, Chu and Chang 2020 p. 2]

Water relations

After six weeks without irrigation, the stems had lost about one-third of their water. From cell dimensions and tissue proportions, the author estimated that approximately 95% of the lost water came from the water-storage parenchyma. This value describes a tissue’s contribution to water loss. The distribution of initial reserves and direct flow between tissues describe separate quantities. [Nobel 2006, p. 469, 471–473]

In 2005, Graham and Nobel measured stem thickness, transpiration and CO₂ uptake simultaneously. In well-watered plants, they observed stems with gas exchange concentrated at night as well as younger segments with substantial daytime CO₂ uptake. These patterns were accompanied by different daily thickness rhythms. Segment age and measurement conditions therefore help interpret the contribution of individual CAM phases. [Graham and Nobel 2005, p. 13–19]

Flowers and cultivation

Temperature acts together with day length. Chu and Chang studied two- and three-year-old plants of the white-fleshed cultivar ‘VN White’ under a fourteen-hour day. At 32/22°C, floral buds emerged after three to four weeks. At 29/19°C, emergence required nine weeks in the second experiment. These values describe that cultivar and procedure. In Poland, planning flowering should combine supplementary lighting with temperature measurements, stem age and plant condition. [Chu and Chang 2020, p. 1–6]

Dragon fruit flowers open at night, and in some material they remain accessible in the morning. In a cultivated Selenicereus undatus population in the Tehuacán Valley, nocturnal visitors contributed to effective pollination. Pollen was found on bats, while honeybees visited flowers during the day. The authors obtained fruits after both self- and cross-pollination. They detected no nectar secretion in the flowers studied and considered pollen feeding as a reason for bat visits. [Valiente-Banuet et al. 2007, pp. 3–7]

Prolonged chamber exposure to 40/30°C caused progressive stem necrosis. This result and water-relations experiments support assessing temperature, hydration and exposure duration together. The dragon fruit cultivation article brings together growing-position, support and reproductive requirements, while the physiological article develops stem mechanisms. [Nobel and De la Barrera 2002, Nobel and de la Barrera 2002 p. 227–230, Nobel 2006 p. 469–473] [Nobel 2006, Nobel and de la Barrera 2002 p. 227–230, Nobel 2006 p. 469–473]

Pollen compatibility in a fruiting cultivar

The white-fleshed cultivar ‘NDFW-1’ was self-compatible in Jadhav and colleagues’ experiments in India. Hand cross-pollination nevertheless increased fruit mass compared with hand self-pollination and open pollination. The study covered 2023–2024 and ten-year-old trellised plants. The self-compatibility finding applies to this cultivar. Clone name, provenance and controlled-pollination results are useful when characterizing one’s own material. [Jadhav et al. 2025, pp. 3–4, 12–13]

Related articles

Materials from the author's archive

The species also appears in Konrad Szychowski's private material archive. [Kaktusy i Inne 2006a, file p. 33]