Tephrosia vogelii J.D. Hooker
Family
Leguminosae
Synonyms
Cracca vogelii (J.D. Hooker) O. Kuntze.
Vernacular Names
| English |
Vogel’s tephrosia, fish-poison bean. |
| Papua New Guinea | Pilawa. |
| Laos | Hu: kata:yx (Vientiane). |
Geographical Distributions
Tephrosia vogelii is native to tropical Africa. It was introduced to tropical America and South and Southeast Asia as a cover crop. It was introduced into Java in 1908 and is now found throughout Malesia.
Description
Tephrosia vogelii is a soft, woody, branching herb or small tree with dense foliage, reaching up to 0.5-4 m tall and with velutinous to sericeous indumentum. The stem and branches are covered with long and short, white or rusty-brown hairs.
The leaves are arranged spirally and imparipinnate. The stipules measure 10-22 mm x 3-3.5 mm and early caducous. The rachis is 5-25 cm long including the cushion-shaped petiole, which is up to 3 cm long. The petiolule is 1.5-5 mm long while the leaflets are in 5-14 pairs that are narrowly elliptical to elliptical-oblanceolate, measuring up to 7 cm x 2 cm, with acute to obtuse base and rounded to emarginated at apex. The venation is most distinct on the lower surface and it is silky hairy.
The inflorescence is a terminal or axillary pseudoraceme, measuring 8-26 cm long and with rusty hairs. The basal bracts are leaf-like. The peduncle is stout, and as long as the pseudoraceme. The flowers are in fascicles of 2. The bracts to fascicles are orbicular to obovate, cuspidate and measuring about 1.5 cm long while the bracts to flowers are narrowly elliptical to spoon-shaped and measuring about 1 cm long. The flower is 18-26 mm long, fragrant when fresh, white, violet, purple or blue. The pedicel is up to 23 mm long. The bracteoles are sometimes present on the sepal. The sepal is bell-shaped, with tube measuring 4-6 mm x 6.510 mm, pale greenish brown, sometimes sericeous outside, usually 4-toothed, with minutely pubescent to sericeous teeth, with broadly ovate vexillary tooth, measuring 5-12 mm x 8-12 mm, with oblong lateral teeth 4.5-10 mm long and rounded at apex. The carina is narrow, boat-shaped, measuring 6-15 mm long and acute. The standard is suborbicular, auricled at the base, emarginated at the apex, and measuring 20-28 mm x 24-32 mm. The apical is half while the margins are minutely pubescent to sericeous within and with claw 3-5.5 mm long. The clawed wings are with the size of 17-22 mm x 11-13 mm, auricled and sericeous inside. The keel measures 15-20 mm x 10-12 mm, slightly auricled, clawed and hairy only on carinal side. There are 10 stamens. The staminal tube is 19-20 mm long and hairless while the vexillary filament is free at the base and connate halfway. It is 22-26 mm long and hairless while the free parts of the other stamens are alternately longer (6-11 mm) and shorter (4-7 mm). The style bends up to 70°. It is 11-15 mm long, bearded on both sides and with hairless stigma.
The pod is linear, slightly turgid, measuring 5.5-14 cm x 0.8-1.8 cm, brown or green, woolly to sericeous and 6-18-seeded. The dark brown to black seed is ellipsoid to kidney-shaped and measuring 5-7 mm x 3-5 mm. Seedling is with epigeal germination. The cotyledons are rather thin, leaf-like, green and long persistent, where the first leaf is simple while the second is usually 3-foliolate.
Ecology / Cultivation
Tephrosia vogelii is found in widely varying habitats, including savanna-like vegetation, grasslands, forest margins and shrublands, waste lands and fallow fields. It is tolerant to drought, strong wind and grazing. Burning has little effect on T. vogelii, as it resprouts readily due to its deep root system. It occurs in climates with annual rainfall of 850-2650 mm and annual mean temperature of 12.5-26.2°C and is found up to 2100 m altitude. It grows well on andosols not subject to flooding and in well drained loams with pH 5.0-6.5, and is also tolerant to poor soils with low pH. In acid soil, it grows much better than Leucaena leucocephala (Lamk) de Wit and forms root nodules which bind with atmospheric nitrogen where the latter does not. In poor soils, however, growth of T. vogelii is slow and more prone to diseases.
Line Drawing / Photograph
References
- Plant Resources of South-East Asia No. 11: Auxiliary plants.
