Gnidia glauca (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Medicinal
Fibre

Gnidia glauca (Fresen.) Gilg

Protologue: Bot. Jahrb. Syst. 19: 265 (1894).

Family: Thymelaeaceae

Synonyms

• Lasiosiphon glaucus Fresen. (1838),
• Gnidia eriocephala Meisn. (1841).

Vernacular names

• Fish-poison bush (En).

Origin and geographic distribution

Gnidia glauca is widely distributed in tropical Africa, from Nigeria eastward to Sudan and Ethiopia and southward to Malawi and Zambia. It also occurs in southern India and in Sri Lanka.

Uses

Fibre from the bark is made into rope and thread. The bark is used for lighting fire. A decoction of the boiled root is drunk in East Africa for treatment of indigestion. In Ethiopia root powder mixed with skimmed milk is taken orally for seven days for treatment of rabies. The bark is made into arrow poison in Kenya: it is boiled in water for several hours and the residue is smeared on arrow tips. In India the bark and leaf are used for treatment of blisters, swellings and contusions, leaf extracts are used as insecticide and the stem, bark and leaf as a fish poison. In Sri Lanka the ground whole plant is used as an insecticide and piscicide.

Properties

The bark fibre is strong and said to be poisonous. An alcohol extract of the root showed strong in-vivo inhibitory activity against P-388 leukaemia in mice. Extracts of the fresh bark exhibited larvicidal activity against Aedes aegypti. Leaf extracts exhibited some insecticidal activity against Aedes aegypti, Anopheles stephensi, Culex pipiens pallens, Culex quinquefasciatus, Plutella xylostella and Spodoptera litura, and fungicidal activity against Venturia inaequalis. Aqueous extracts of the leaf showed some antifeedant activity against the armyworm Helicoverpa armigera. In Sri Lanka the leaf and twig were found to contain alkaloids.

Description

Large, much-branched shrub up to 6 m tall or small tree up to 15(–24) m tall; outer bark grey, brown or blackish, smooth to wrinkled; inner bark fibrous, pale yellow, fragrant. Leaves alternate, clustered in the upper parts of branches, simple and entire, almost sessile or with petiole 1–3 mm long; stipules absent; blade narrowly elliptical to obovate, (20–)25–65(–85) mm × 6–26 mm, gradually narrowed to the base, rigid, hairy or glabrous, glaucous, midvein prominent beneath. Inflorescence a dense terminal head 2–5 cm in diameter, 20–70-flowered; peduncle widening towards the top, hairy; bracts 6–12(–15), elliptical to ovate, 10–15 mm × 4–10 mm, slightly leathery, softly hairy on both sides, cream-coloured or salmon-pink, persistent. Flowers bisexual, regular, (4–)5-merous, orange or golden yellow, fading to brown; pedicel 1–2.5 mm long, hairy; calyx tube cylindrical, 9–14 mm long, without articulation, the upper part softly hairy, the lower part with dense tufts of silky hairs 2–4 mm long, lobes imbricate, ovate, entire or lobed, 2.5–5 mm × 1.5–2 mm, hairy outside; petals inserted in the throat of the calyx tube, elliptical or spathulate, 1–2 mm long, entire, emarginate or lobed, membranous or fleshy; stamens (8–)10, in 2 whorls of unequal length, inserted in the throat of the calyx tube, upper whorl slightly exserted; ovary superior, 1-locular, hairy, style filiform, 6–10 mm long. Fruit enclosed by the persistent base of the calyx tube. Seeds 3–4 mm × 1.5–2 mm, black.

In Kenya Gnidia glauca flowers in February–March and May–July.

Gnidia comprises about 140 species, mainly distributed in tropical Africa, with 20 species endemic to Madagascar, but it also extends into Arabia, western India and Sri Lanka. Gnidia glauca var. glauca is distributed in tropical Africa and southern India, whereas Gnidia glauca var. insularis (Gardner) C.C.Towns. is endemic to Sri Lanka. The latter has twigs and leaves more or less densely covered with persistent long appressed hairs, whereas those of the former are glabrescent.

Ecology

Gnidia glauca occurs at 950–3300 m altitude, in forest margins and associated bushland or wooded grassland, on rocky grassy slopes and around stream beds. In East Africa it is sometimes locally dominant in secondary forest.

Genetic resources

In view of its wide distribution and local abundance, Gnidia glauca is not threatened by genetic erosion.

Prospects

Gnidia glauca yields a strong fibre suitable for cordage, but detailed information on the fibre properties is unavailable, making it difficult to assess its prospects. The plant has toxic properties and is used as an insecticide and piscicide. Research on its phytochemistry and the risks of its use for human health and the environment seems warranted.

Major references

• Beentje, H.J., 1994. Kenya trees, shrubs and lianas. National Museums of Kenya, Nairobi, Kenya. 722 pp.

• Coates Palgrave, K., 1983. Trees of southern Africa. 2nd Edition. Struik Publishers, Cape Town, South Africa. 959 pp.

• Greenway, P.J., 1950. Vegetable fibres and flosses in East Africa. The East African Agricultural Journal 15(3): 146–153.

• Peterson, B., 1978. Thymelaeaceae. In: Polhill, R.M. (Editor). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 37 pp.

• Peterson, B., 2006. Thymelaeaceae. In: Pope, G.V., Polhill, R.M. & Martins, E.S. (Editors). Flora Zambesiaca. Volume 9, part 3. Royal Botanic Gardens, Kew, Richmond, United Kingdom. pp. 85–117.

Other references

• Amarajeewa, B.W.R.C., Mudalige, A.P. & Kumar, V., 2007. Chemistry and mosquito larvicidal activity of Gnidia glauca. Proceedings of the Peradeniya University Research Sessions 12(1): 101–102.

• Bussmann, R.W., 2006. Ethnobotany of the Samburu of Mt. Nyiru, South Turkana, Kenya. Journal of Ethnobiology & Ethnomedicine 2: 35.

• Eggeling, W.J. & Dale, I.R., 1951. The indigenous trees of the Uganda Protectorate. Government Printer, Entebbe, Uganda. 491 pp.

• Kokwaro, J.O., 1993. Medicinal plants of East Africa. 2nd Edition. Kenya Literature Bureau, Nairobi, Kenya. 401 pp.

• Ohigashi, H., Takagaki, T., Koshimizu, K., Watanabe, K., Kaji, M., Hoshino, J., Nishida, T., Huffman, M.A., Takasaki, H., Jato, J. & Muanza, D.N., 1991. Biological activities of plant extracts from tropical Africa. African Study Monographs 12(4): 201–210.

• Peterson, B., 1976. A new species of Gnidia (Thymelaeaceae) from Mlanje and Namuli mountains. Kew Bulletin 31(1): 177–179.

• Sakthivadivel, M. & Daniel, T., 2008. Evaluation of certain insecticidal plants for the control of vector mosquitoes viz. Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. Applied Entomology and Zoology 43(1): 57–63.

• Sommerlatte, H. & Sommerlatte, M., 1990. A field guide to the trees and shrubs of the Imatong Mountains, southern Sudan. Deutsche Gesellschaft fur Technische Zusammmenarbeit (GTZ), Nairobi, Kenya. 372 pp.

• Sundararajan, G. & Kumuthakalavalli, R., 2001. Antifeedant activity of aqueous extract of Gnidia glauca Gilg. and Toddalia asiatica Lam. on the gram pod borer, Helicoverpa armigera (hbn). Journal of Environmental Biology 22(1): 11–14.

• Teklehaymanot, T. & Giday, M., 2007. Ethnobotanical study of medicinal plants used by people in Zegie Peninsula, Northwestern Ethiopia. Journal of Ethnobiology and Ethnomedicine 3: 12.

Author(s)

• M. Brink, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Correct citation of this article

Brink, M., 2009. Gnidia glauca (Fresen.) Gilg. [Internet] Record from PROTA4U. Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.

Accessed 22 December 2024.

• See the Prota4U database.