Prota 2: Vegetables/Légumes
Bot. Jahrb. 33: 121 (1902).
Origin and geographic distribution
Urera cordifolia occurs in Nigeria, Cameroon, Central African Republic and Gabon. It is part of a complex of closely related species, including Urera flamigniana Lambinon, Urera gravenreuthii Engl. and Urera mannii (Wedd.) Benth. & Hook.f. ex Rendle, having different distribution areas in West and Central Africa.
The leaves of Urera cordifolia and related species are eaten in soups and as a mucilaginous cooked vegetable. The bark fibre is strong and used for ropes and fishing lines. There are numerous local medicinal uses reported of leaf sap, leaf decoctions and dried, powdered leaves, e.g. to treat dysentery, neuralgia, deafness and other ear affections, diarrhoea with blood, chest pain, male impotency and furuncles, as an aphrodisiac and laxative, and as a component of arrow poison. The whole plant is used as a diuretic. The sap of crushed inflorescences is taken as a poison antidote. The small red fruits are used as a bait in bird traps.
Aqueous leaf extracts of the Neotropical Urera baccifera (L.) Wedd. have demonstrated anti-inflammatory and analgesic activities, but nothing is known about the phytochemistry of the African Urera species.
Dioecious liana up to 10 m long; stem c. 3 cm in diameter, attached by adventitious roots, 5-lobed in cross-section, older branches with 5 rows of prickle-like protuberances, young branches with stinging hairs, these also on leaves and inflorescences. Leaves alternate, simple; stipules connate, bifid, early caducous; petiole up to 12(–36) cm long; blade orbicular to ovate, up to 18(–45) cm long, base rounded to slightly cordate, apex acuminate, margin crenate to dentate, 3-veined from the base. Inflorescence an axillary, lax panicle; male inflorescence up to 16 cm long; female inflorescence up to 6 cm long. Flowers unisexual, regular, small; male flowers with c. 2 mm long pedicel, reddish; female flowers sessile, c. 1 mm long. Fruit an achene up to 2 mm long, surrounded by the perianth.
Urera comprises about 35 species and occurs in tropical Africa including Madagascar, tropical America and Hawaii. The taxonomy of the West African Urera species is incompletely known. The fact that leaf morphology has usually been the basis for separating species seems to be the underlying problem.
Like other Urera species, Urera cordifolia occurs in dense, humid, lowland forest.
Genetic resources and breeding
Utilization by man does not seem to pose a serious threat to Urera cordifolia and related species, which are threatened more by destruction of lowland forest.
The use of Urera cordifolia as a vegetable is likely to remain restricted. Despite the numerous medicinal local uses, there is no indication of interest from phytochemists or pharmacologists. A taxonomic revision of West African Urera species is long overdue.
• Burkill, H.M., 2000. The useful plants of West Tropical Africa. 2nd Edition. Volume 5, Families S–Z, Addenda. Royal Botanic Gardens, Kew, United Kingdom. 686 pp.
• Keay, R.W.J., 1958. Urticaceae. In: Keay, R.W.J. (Editor). Flora of West Tropical Africa. Volume 1, part 2. 2nd Edition. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. pp. 616–623.
• Letouzey, R., 1968. Urticaceae. Flore du Cameroun. Volume 8. Muséum National d’Histoire Naturelle, Paris, France. pp. 67–216.
• Busson, F., 1965. Plantes alimentaires de l’ouest Africain: étude botanique, biologique et chimique. Leconte, Marseille, France. 568 pp.
• Kerharo, J. & Bouquet, A., 1950. Plantes médicinales et toxiques de la Côte d’Ivoire - Haute-Volta. Vigot Frères, Paris, France. 291 pp.
Correct citation of this article:
Bosch, C.H., 2004. Urera cordifolia Engl. In: Grubben, G.J.H. & Denton, O.A. (Editors). PROTA 2: Vegetables/Légumes. [CD-Rom]. PROTA, Wageningen, Netherlands.