Ravenala madagascariensis (PROTA)

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Plant Resources of Tropical Africa
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distribution in Africa (wild and naturalized)
1, plant habit; 2, inflorescence; 3, flower; 4, dehisced fruit; 5, seed Redrawn and adapted by M.M. Spitteler
habit
habit
detail of inflorescence
infructescence
thatch made of leaves

Ravenala madagascariensis Sonn.


Protologue: Voy. Indes orient. Ed. 1, 2: 223, t. 124–126 (1782).
Family: Strelitziaceae
Chromosome number: 2n = 22

Vernacular names

  • Traveller’s palm, traveller’s tree (En).
  • Arbre du voyageur (Fr).
  • Palmeira do viajante (Po).
  • Árbol del viajero (Sp).

Origin and geographic distribution

Traveller’s palm is endemic to Madagascar, and naturalized in the Mascarene Islands. It is widely planted as an ornamental tree throughout the tropics.

Uses

The traveller’s palm is very commonly planted for ornamental purposes. The leaves are arranged into 2 rows, giving the impression of a gigantic fan. The vernacular names are an indication of the alleged use by travellers, who are said to have drunk rain water accumulated in the basal cup of the petiole and in the flower bracts. However, this water is often rendered undrinkable by infestation with mosquito larvae and contamination by detritus.

Ravenala madagascariensis is economically important locally along the east coast of Madagascar, where the leaves are used for roofing, the petioles for walls and the bark for floors in houses. In parts of India, the stem is used in house construction, the leaves for packing material and for roofing, and the midribs and petioles for hut walls.

Sugar can be extracted from the sap of the trunk. The seeds are edible, but mealy, and the edible arils are tasteless. The seed oil is sometimes used for cooking, and is reported to be antiseptic. The pith from the trunk is sometimes used as a fodder for livestock.

Properties

The oil content of the seeds and arils is 4% and 68%, respectively. The oils have a fatty acid composition intermediate between palm oil and cocoa butter (oleic acid 39% and palmitic acid 34–42%) and form a possible minor source of vegetable butter. Analysis of the sterol fraction of the seed oil revealed 7 sterols, mainly β-sitosterol (65%), whereas 12 sterols have been isolated from the aril oil, mainly stigmasterol (18%), 24-methyl-5α-cholest-7-en-3-β-ol (16%), α-spinasterol (28%) and Δ-7-avenasterol (19%).

Description

  • Medium-sized evergreen tree, up to 20(–30) m tall; roots rhizomatous; trunk solitary or branched at base, cylindrical, woody, ring-scarred, olive green and smooth or grey and fissured, apical third clothed by leaf bases; crown fan-like, with 20 or more leaves.
  • Leaves alternate, distichously arranged, simple; petiole 3–6 m long, stout, channelled, with air canals, arising at 45° to axis, base cup-shaped, broadly sheathing and overlapping; blade oblong, 2.5–4(–5) m × 0.8–1.5 m, base and apex rounded, entire but often torn at the veins, glabrous, dull green, midrib sulcate, pale, with closely set, parallel veins.
  • Inflorescence an axillary thyrse, bearing cincinnate flower clusters enclosed in distichously arranged, large, stiff, boat-shaped bracts 20–25(–30) cm long, whitish.
  • Flowers bisexual, slightly zygomorphic, 3-merous, subtended by carinate bracteoles, all flower parts creamy white; sepals free, lanceolate, subequal, up to 20 cm long, long-acuminate; petals free, lanceolate, up to 15 cm long, posterior one shorter than other 2; nectaries with copious nectar; stamens 6 in 2 whorls of 3, up to 16 cm long, anthers basifixed, dehiscing via longitudinal slits; ovary inferior, 3-locular, style long, straight, stigma with finger-like protuberances.
  • Fruit an oblong, woody, loculicidal capsule 2–4 cm long, many-seeded.
  • Seeds ovoid, ca. 0.5 cm long, glabrous, brown, with abundant endosperm, surrounded by a blue to purple, laciniate-lobed aril.
  • Seedling with hypogeal germination, cotyledon single, massive, tip remaining in the seed-coat as an absorbing organ.

Other botanical information

The monotypic Ravenala is one of 3 genera in the Strelitziaceae, the others being the monotypic Phenakospermum from the swamps of South America and Strelitzia with 5 species from southern Africa. Strelitziaceae is closely related to Musaceae, Heliconiaceae and Lowiaceae.

In eastern Madagascar, 4 forms of Ravenala madagascariensis have been observed on the slopes of the hills, from sea-level up to 1000 m altitude. The first form, locally called ‘malama’, is rather rare and grows in the understorey of undisturbed submontane rain forest. The juvenile phase is characterized by a secondarily spiral arrangement of the leaves, a long-decurrent leaf blade, the absence of a petiole, and the arrangement of the leaves to form a torus; the adult phase has a fan-like crown. The second form, ‘hiranirana’, is more abundant in forest gaps and disturbed primary forest, and the juvenile phase is more similar to the usual fan-like form, with well-developed petioles and a relatively wide leaf blade, and a slight and regularly alternate arrangement of the leaves, persisting in the adult phase. The third form, ‘bemavo’ is the most common form, growing on deforested slopes between 300–600 m altitude, and forming Ravenala forests; all phases show a fan-like crown. This form is mostly used for construction purposes. The fourth form, ‘horonorona’ grows in deforested lowland sites, on either poorly or well-drained soils, and is different from the other 3 in that it stays rather small and develops many suckers. It is the form that is most commonly cultivated.

Growth and development

The leaves at the base of a new shoot often consist often only of sheaths. Each new leaf grows up inside the sheath of the preceding one, the blade being tightly rolled. A fully expanded leaf is often slightly unequal-sided, or the base of the blade is asymmetrical. It takes up to 10 years before first flowering, but because traveller’s palm is planted for its foliage this does not distract from its ornamental value.

Every 2–3 days, a new flower opens in an inflorescence, the total number of open flowers being variable; up to 29 have been counted. The flowers normally open at night. Nectar production is copious, with maximum production at midnight. In Madagascar, traveller’s palm is pollinated predominantly by several lemur species, e.g. the ruffled lemur (Varecia variegata) and the black lemur (Eulemur macaco). Lemurs appear to be highly dependent on the nectar of traveller’s palm during specific times of the year. In areas outside the natural range, flowers are often visited by large bats, such as Pteropus alecto gouldii and Macroglossus lagochilus, as well as honeyeater birds (Megaphagidae) in Australia. The 2 abaxial petals are linked by interlocking papillae to form a tube around the anthers. At anthesis, they separate with an explosion that sheds the pollen onto a potential pollinator. Autogamy treatments revealed that Ravenala madagascariensis is a facultative self-fertilizer.

Ecology

Traveller’s palm prefers sheltered, warm and humid and per-humid areas near the coast, from sea-level up to 450 m altitude, but it can be found up to 1000 m.

Propagation and planting

Propagation is by seed and suckers. Seed is best sown in a moist, sandy soil at 20°C. Seedlings of 2–6 months old are planted in a rich, deep, loamy soil in full sunlight, incorporating organic matter at planting to prevent drying of the roots. Suckers grow at irregular intervals, close to the parental stem. Rooted suckers are separated at the beginning of the rainy season, and are directly planted into fertile soil for quick growth.

Diseases and pests

Ravenala madagascariensis is a host of the fungus Colletotrichum gloeosporioides, which causes leaf spot disease of, for example, areca nut palm (Areca catechu L.) in India. There the roots of traveller’s palm are also attacked by the root-knot nematode Meloidogyne incognita.

Genetic resources

As Ravenala madagascariensis is widely planted throughout the tropics, there seems to be no risk of genetic erosion, although the genetic diversity of plants in cultivation is unknown. No germplasm collections are known.

Prospects

As traveller’s palm is a popular ornamental tree that is widely grown, the development of cultivars with different habits might be a good trade option. As deforestation in Madagascar proceeds at an alarming rate, protection of the tree from uncontrolled cutting may soon be necessary.

Major references

  • Blanc, P., Rabenandrianina, N., Hladik, A. & Hladik, C.M., 1999. Les formes sympatriques et allopatriques du genre Ravenala dans les fôrets et les milieux ouverts de l’est de Madagascar. Revue d’Ecologie la Terre et la Vie 54(3): 201–223.
  • Huxley, A. (Editor), 1992. The new Royal Horticultural Society dictionary of gardening. Volume 3. MacMillan Press, London, United Kingdom. 790 pp.
  • Kress, W.J., Schatz, G.E., Andrianifahanana, M. & Morland, H.S., 1994. Pollination of Ravenala madagascariensis (Strelitziaceae) by lemurs in Madagascar: evidence for an archaic coevolutionary system? American Journal of Botany 81(5): 542–551.
  • Rabarisoa, I., Bianchini, J.P. & Gaydou, E.M., 1981. Composition des huiles extraites du fruit de Ravenala madagascariensis. Canadian Journal of Plant Science 61(3): 691–695.

Other references

  • Andersson, L., 1998. Strelitziaceae. In: Kubitzki, K. (Editor). The families and genera of vascular plants. Volume 4. Flowering plants - monocotyledons, Alismatanae and Commelinanae (except Gramineae). Springer-Verlag, Berlin, Heidelberg, Germany. pp. 451–455.
  • Calley, M., Braithwaite, B.W. & Ladd, P.G., 1993. Reproductive biology of Ravenala madagascariensis Gmel. as an alien species. Biotropica 25(1): 61–72.
  • CSIR, 1969. The wealth of India. A dictionary of Indian raw materials & industrial products. Raw materials. Volume 8: Ph–Re. Publications and Information Directorate, Council of Scientific and Industrial Research, New Delhi, India. 394 pp.
  • Dorr, L.J. & Parkinson, P.G., 1990. Proposal to conserve the spelling 1320 Ravenala (Strelitziaceae). Taxon 39(1): 131–132.
  • Kirchoff, B.K., 1991. Homeosis in the flowers of the Zingiberales. American Journal of Botany 78(6): 833–837.
  • Marais, W., 1983. Musacées. In: Bosser, J., Cadet, T., Guého, J. & Marais, W. (Editors). Flore des Mascareignes. Familles 171–176. The Sugar Industry Research Institute, Mauritius, l’Office de la Recherche Scientifique Outre-Mer, Paris, France & Royal Botanic Gardens, Kew, Richmond, United Kingdom. 7 pp.
  • Perrier de la Bâthie, H., 1946. Musacées (Musaceae). Flore de Madagascar et des Comores (plantes vasculaires), familles 45–48. Imprimerie Officielle, Tananarive, Madagascar. 9 pp.
  • Piepenbring, M. & Napp-Zinn, K., 1992. Comparative anatomical studies on foliar organs of Ravenala madagascariensis Sonn. Beiträge zur Biologie der Pflanzen 67(3): 367–386.

Sources of illustration

  • Andersson, L., 1998. Strelitziaceae. In: Kubitzki, K. (Editor). The families and genera of vascular plants. Volume 4. Flowering plants - monocotyledons, Alismatanae and Commelinanae (except Gramineae). Springer-Verlag, Berlin, Heidelberg, Germany. pp. 451–455.
  • Petersen, O.G., 1889. Musaceae. In: Engler, A. & Prantl, K. (Editors). Die natürlichen Pflanzenfamilien 2. Band. 6. Wilhelm Engelman, Leipzig, Germany. pp. 1–10.
  • Perrier de la Bâthie, H., 1946. Musacées (Musaceae). Flore de Madagascar et des Comores (plantes vasculaires), familles 45–48. Imprimerie Officielle, Tananarive, Madagascar. 9 pp.

Author(s)

  • G.H. Schmelzer, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Correct citation of this article

Schmelzer, G.H., 2002. Ravenala madagascariensis Sonn. [Internet] Record from PROTA4U. Oyen, L.P.A. & Lemmens, R.H.M.J. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.

Accessed 9 July 2021.