Alternanthera littoralis (PROTA)
Introduction |
General importance | |
Geographic coverage Africa | |
Geographic coverage World | |
Vegetable | |
Medicinal | |
Auxiliary plant | |
Food security | |
Alternanthera littoralis P.Beauv.
- Protologue: Fl. Oware 2: 72 (1818).
- Family: Amaranthaceae
Synonyms
- Bucholzia maritima Mart. (1826),
- Alternanthera maritima (Mart.) A.St.-Hil. (1833),
- Telanthera maritima (Mart.) Moq. (1849).
Origin and geographic distribution
Alternanthera littoralis is recorded in Africa along the Atlantic coast from Senegal to Angola, and from Madagascar. It also occurs along the Atlantic coast of South America.
Uses
The leaves of Alternanthera littoralis are collected from the wild and eaten as a cooked vegetable by various ethnic groups in Atlantic coastal regions in Africa. Because of its long stolons the plant is also a useful sand-binder. In Côte d’Ivoire it is medicinally used as an alterative for children and pulped up it is applied to frictions to treat oedema.
Properties
The leaves of Alternanthera littoralis contain per 100 g: water 78.5 g, energy 230 kJ (55 kcal), protein 5.0 g, fat 0.9 g, carbohydrate 10.0 g, fibre 2.2 g, Ca 142 mg, P 35 mg (Leung, W.-T.W., Busson, F. & Jardin, C., 1968).
Description
- Creeping, fleshy herb with stoloniferous, angular, glabrescent stems up to 10 m long, rooting at the nodes.
- Leaves opposite, simple, fleshy, pubescent; petiole c. 2 mm long; blade oblanceolate to obovate, 3–5 cm × 1.5–3 cm, base attenuate, apex with a small point, margin entire.
- Inflorescence an axillary, sessile, ovoid head, up to 1.5 cm × 1 cm, usually solitary or in pairs, up to 20-flowered.
- Flowers bisexual, regular, 5-merous, white; tepals unequal, 2 external ones concave, 6.5 mm long, pubescent and with 3 thick veins, internal ones narrower, 4.5 mm long, glabrous, with only 1 thick vein; stamens 3 mm long, united in lower third, filaments and anthers about equal in length, staminodes alternating with stamens, with 3–5 lobes at apex; ovary superior, subglobular, 1-celled, glabrous, style distinct, with head-like, papillose stigma.
- Fruit an indehiscent, obovoid capsule with thin wall, 1-seeded.
- Seed subglobose, c. 1 mm in diameter, glossy brown.
Alternanthera comprises about 200 species, distributed pantropically but most abundantly in tropical America. In tropical Africa about 6 species are found.
Mainly based on the degree of hairiness of leaves and tepals, 4 varieties of Alternanthera littoralis have been distinguished, 3 of which occur in Africa. However, delimitations are not sharp.
Ecology
Alternanthera littoralis grows in coastal sands down to the high-water mark. In Senegal it colonizes the tops of coastal sand dunes and helps to bind them with its long stolons. The plant is a pronounced halophyte; it flowers and fruits year-round.
Genetic resources
Alternanthera littoralis is widespread and not in danger of genetic erosion.
Prospects
Alternanthera littoralis will remain a minor vegetable, which is only locally of importance. Its ability to grow on soils with a high salt concentration combined with its sand-binding properties deserve further research.
Major references
- Burkill, H.M., 1985. The useful plants of West Tropical Africa. 2nd Edition. Volume 1, Families A–D. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 960 pp.
- Burkill, H.M., 2000. The useful plants of West Tropical Africa. 2nd Edition. Volume 5, Families S–Z, Addenda. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 686 pp.
- Leung, W.-T.W., Busson, F. & Jardin, C., 1968. Food composition table for use in Africa. FAO, Rome, Italy. 306 pp.
Other references
- Bouquet, A. & Debray, M., 1974. Plantes médicinales de la Côte d’Ivoire. Travaux et Documents No 32. ORSTOM, Paris, France. 231 pp.
- Cavaco, A., 1954. Amaranthacées (Amaranthaceae). Flore de Madagascar et des Comores (plantes vasculaires), familles 66–69. Firmin-Didot et cie., Paris, France. 56 pp.
- Cavaco, A., 1974. Amaranthaceae. Flore du Cameroun. Volume 17. Muséum National d’Histoire Naturelle, Paris, France. 65 pp.
- Hauman, L., 1951. Amaranthaceae. In: Robyns, W., Staner, P., Demaret, F., Germain, R., Gilbert, G., Hauman, L., Homès, M., Jurion, F., Lebrun, J., Vanden Abeele, M. & Boutique, R. (Editors). Flore du Congo belge et du Ruanda-Urundi. Spermatophytes. Volume 2. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 12–81.
- Kerharo, J. & Bouquet, A., 1950. Plantes médicinales et toxiques de la Côte d’Ivoire - Haute-Volta. Vigot Frères, Paris, France. 291 pp.
- Lemmens, R.H.M.J. & Horsten, S.F.A.J., 1999. Alternanthera Forssk. In: de Padua, L.S., Bunyapraphatsara, N. & Lemmens, R.H.M.J. (Editors). Plant Resources of South-East Asia No 12(1). Medicinal and poisonous plants 1. Backhuys Publishers, Leiden, Netherlands. pp. 105–109.
- Pedersen, T.M., 1990. Studies in South American Amaranthaceae 3 (including one amphi-Atlantic species). Bulletin du Muséum National d'Histoire Naturelle, 4e Série. Section B, Adansonia, botanique, phytochimie 12: 69–97.
- Raponda-Walker, A. & Sillans, R., 1961. Les plantes utiles du Gabon. Paul Lechevalier, Paris, France. 614 pp.
Author(s)
- P.C.M. Jansen, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
Correct citation of this article
Jansen, P.C.M., 2004. Alternanthera littoralis P.Beauv. [Internet] Record from PROTA4U. Grubben, G.J.H. & Denton, O.A. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands.
Accessed 18 December 2024.