Tephrosia purpurea (L.) Pers.
Family
Leguminosae
Synonyms
Cracca purpurea L., Tephrasia diffusa (Roxb.) Wight & Arnott, Tephrosia wallichii Grah. ex Fawc. & Rendle.
Vernacular Names
|
English |
Purple tephrosia, wild indigo. |
|
American |
Fish poison. |
|
Indonesia |
Pohon nila hutan (Java). |
|
Philippines |
Balatong-pula, balba-Iatong, tina-tinaan (Tagalog). |
|
Cambodia |
Trôm’ khmaôch. |
|
Laos |
S’a:z kh’a:m moyz (Louang Prabang). |
|
Thailand |
Khram-pa (northern). |
|
Vietnam |
C[aa]y c[oos]t kh[is] t[is]a, ve c[as]i, do[ax]n ki[ees]m d[or]. |
|
French |
Indigo sauvage. |
Geographical Distributions
Tephrosia purpurea is native to tropical Asia, and is found from India and Sri Lanka to southern China, and through Southeast Asia to tropical Australia and the Polynesian Islands. It is now naturalised and cultivated pantropically.
Description
Tephrosia purpurea is an erect or spreading, annual or short-lived perennial herb that is sometimes bushy. It can grow 40-80 cm tall and rarely up to 1.5 m. The indumentum is silky. The stem is slender, erect or decumbent at the base.
The leaves are imparipinnate. The stipules are narrowly triangular and measure 1.5-9 mm x 0.1-1.5 mm. The rachis is up to 14.5 cm long while the petiole is up to 1 cm. The petiolule is 1-3 mm long. There are 5-25 leaflets which are obovate to narrowly elliptical. The terminal leaflet measures 7-28 mm x 2-11 mm while the lateral leaflet measures 5-30 mm x 2-11 mm. It is acute at the base and rounded to emarginate at the apex. The veins arrangement is usually distinct on both surfaces.
The inflorescence is an axillary or leaf-opposed pseudoraceme, measures (1.5-)10-15(-25) cm long and sometimes with basal leaf-like bracts. The flowers are in fascicles of 4-6. The bracteoles are usually absent and the pedicel is 2-6 mm long. The flower is 4-8.5 mm long and purplish to white. The sepal is bell-shaped, persistent, with the cup size of 1.4-2.3 mm x 1.5-3.2 mm, unequally 4-toothed and with pubescent teeth inside. The upper part of petal is broadly ovate, measures 3.5-7.3 mm x 5-10 mm and clawed. The wings measure 2.5-6 mm x 1.5-3.8 mm, auricled on vexillary side and clawed. The keel measures 2.2-4.5 mm x 2-3 mm, auricled on vexillary side and clawed. There are 10 stamens, and with staminal tube 4-6 mm long. The filaments are alternately longer and shorter where the free part is up to 3.5 mm long while the vexillary filament is 5-8 mm long, free at the base and connate halfway. The style is up to 4.5 mm long where the upper half is hairless and with penicillate stigma at the base.The pod is flat, linear, measuring 2-4.5 cm x 3-5 mm, somewhat up-curved towards the end, convex around the seeds, flattened between, with thickened margins and dehiscent with twisted valves. It contains 2-8(-10) seeds. The seed measures 2.5-5 mm x 1.8-3 mm which is rectangular to transversely ellipsoid, light to dark brown to black and sometimes mottled.
Ecology / Cultivation
Tephrosia purpurea occurs naturally in grassy fields, waste places and thickets, on ridges, and along roadsides, in Java up to 400 m altitude. It generally grows at low altitudes, but may be found to 1300 m altitude. In Hawaii, it grows near the seashore. It prefers dry, gravelly or rocky and sandy soils, but in Madras (India), it grows well on loamy soils. It is tolerant of saline-sodic soil conditions.
Line Drawing / Photograph
References
- Plant Resources of South-East Asia No.11: Auxiliary plants.
