Crotalaria retusa (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Crotalaria retusa L.

Family: Leguminosae - Papilionoideae

Vernacular names

• Devil bean, large yellow rattlebox, wedge-leaved crotalaria (En)
• Indonesia: orok-orok cina (Java), duku todore (Halmahera)
• Malaysia: giring badak
• Philippines: buli-laua, potokan (Tagalog), palpaltog (Ilokano)
• Cambodia: chhë: krông sva: (Kampot), tra:ch kuël'.

Distribution

Probably of Asian origin, now pantropical, also cultivated.

Uses

Green manure and fibre crop, but it also occurs as a weed. Roots are used against coughing up blood, leaves mixed with those of C. quinquefolia L. act internally as well as externally against fever, scabies, lung diseases and impetigo. Flowers and leaves are sweet, edible as a vegetable, their alkaloid content being very low. The roasted dehulled seeds are eaten in Vietnam. It is also reported to yield toxins, such as the alkaloid monocrotaline and to have poisoned poultry and livestock in Nigeria. It is occasionally grown as an ornamental, and is used as a dye plant in East Africa.

Observations

• Annual herb or subshrub up to 1.2 m tall. Branches glabrous to appressed hairy.
• Leaves simple; blade oblanceolate to oblong, 3-10 cm × 1-4 cm, apex rounded or emarginate, glabrous above, silky pubescent below.
• Inflorescence an erect, terminal raceme, 15-30 cm long; pedicel 4-8 mm long.
• Calyx about 10-14 mm long, subglabrous, upper teeth ovate, acute, 3 lower teeth narrower; corolla 2.5 cm long, yellow, tinged purple.
• Pod subcylindrical, 2.5-5 cm × 1-2 cm, glabrous, stipitate, 15-20-seeded.
• Seed heart-shaped, 5 mm × 3 mm, yellow-brown to blackish.

C. retusa occurs in coastal grassland, along rivers, waste places and fields, up to 250 m altitude. It fixes nitrogen and is self-pollinating. The seed-coat is hard, and germination irregular. It is full-grown in two months. Damage caused by pests is common, but it is resistant to root-knot nematodes.

Selected sources

• Backer, C.A. & Bakhuizen van den Brink Jr., R.C., 1963-1968. Flora of Java. 3 volumes. Wolters-Noordhoff, Groningen, the Netherlands. 647, 641, 761 pp.
• Flora of Tropical East Africa (various editors), 1952-. Crown Agents for Oversea Governments and Administrations, London, United Kingdom & A.A. Balkema, Rotterdam, the Netherlands.
• Flore du Cambodge, du Laos et du Viêt-nam [Flora of Cambodia, Laos and Vietnam] (various editors), 1960-. Volume 1-. Muséum National d'Histoire Naturelle, Laboratoire de Phanérogamie, Paris, France.
• Hacker, J.B., 1990. A guide to herbaceous and shrub legumes of Queensland. University of Queensland Press, St. Lucia, Australia. 351 pp.
• Nasir, E. & Ali, S.I. (Editors), 1970-. Flora of (West) Pakistan. Volume 1-. Department of Botany, University of Karachi, Karachi, Pakistan.
• Polhill, R.M., 1982. Crotalaria in Africa and Madagascar. A.A. Balkema, Rotterdam, the Netherlands. 389 pp.
• Verdcourt, B., 1979. A manual of New Guinea legumes. Botany Bulletin No 11. Office of Forests, Division of Botany, Lae, Papua New Guinea. 645 pp.
• Wealth of India (various editors), 1948-1976. A dictionary of Indian raw materials and industrial products: raw materials. 11 volumes. Publications and Information Directorate, Council of Scientific and Industrial Research, New Delhi, India. 4441 pp.

Authors

• M.S.M. Sosef & L.J.G. van der Maesen