Fabaceae FAMILY

Millettia rhodantha

Edibility

0/5

Medicinal

3/5

Safety & Hazards

Millettia species in general contain a range of toxic substances, especially isoflavones. Rotenone is probably the best known of these isoflavones and it is found especially in the seeds and roots of the plants. Rotenone is often used locally as a fish poison - the rotenone kills or stuns the fish making them easy to catch, but the fish remain perfectly safe for warm-blooded creatures to eat. Rotenone is classified by the World Health Organization as moderately hazardous. It is mildly toxic to humans and other mammals, but extremely toxic to many insects (hence its use as an insecticide) and also to aquatic life, including fish. This higher toxicity in fish and insects is because the lipophilic rotenone is easily taken up through the gills or trachea, but not as easily through the skin or the gastrointestinal tract. The lowest lethal dose for a child is 143 mg/kg, but human deaths from rotenone poisoning are rare because its irritating action causes vomiting. Deliberate ingestion of rotenone, however, can be fatal. The compound decomposes when exposed to sunlight and usually has an activity of six days in the environment. Millettia species often also contain other potentially toxic compounds, especially saponins and alkaloids^[1].

Cultivation Details

HabitTree

Growth—

Plants are tolerant of shade^[2]. Species in this genus generally grow best in a sunny position in a fertile, moisture-retentive but well-drained soil^[3]. Seedlings may be found in the shade, but regeneration is probably most abundant in small gaps in the forest^[2]. The flowers are sweetly scented^[2]. In some areas the plant produces seeds all year round^[2]. This species has a symbiotic relationship with certain soil bacteria; these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby^[4].

Propagation

Seed - usually germinates within 2 weeks of sowing^[2]. Like many species within the family Fabaceae, once they have been dried for storage the seeds of this species may benefit from scarification before sowing in order to speed up and improve germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing^[PFAF]. In experiments in Côte d’Ivoire, inoculation with Bradyrhizobium bacteria 1 month after sowing had a positive effect on plant height and stem diameter measured at 4 and 11 months after inoculation. At 11 months after inoculation, inoculated seedlings were 60cm tall, uninoculated ones only 30cm^[2]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-20. <tropical.theferns.info/viewtropical.php?id=Millettia+rhodantha>

Pollinators

Bees

References

[1]The Leguminosae; A Source Book of Characteristics, Uses and Nodulation — Allen O.N.; Allen E.K. · University of Wisconsin · 1981 · ISBN 0-333-32221-5 ↩︎An amazing and comprehensive work, giving a brief guide to the many genera of the family Fabaceae and also the principle uses of the genus.
[2]Protabase - Plant Resources of Tropical Africa. — http://www.prota.org ↩︎An excellent on-line database with detailed information on over 3,200 species of useful plants of Africa.
[3]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
[4]Nodulation Plants in GRIN Taxonomy — United States Department of Agriculture · http://www.ars-grin.gov/~sbmljw/cgi-bin/taxnodul.pl?language=en ↩︎An online database listing plants that have either positive or negative reports on root and stem nodulation with nitrogen-fixing bacteria.
[5]African Flowering Plants Database — Conservatoire et Jardin Botaniques. · http://www.ville-ge.ch/musinfo/bd/cjb/africa/recherche.php ↩︎Contains information on over 150,000 plant names (including synonyms) giving a description and habitat, plus a distribution map.
[6]Cataloge of African Plants Collected by Dr. Friedrich Welwitsch in 1853 - 1861 — Hiern. W.P. · Longmans & Co.; London. · 1898 · http://www.biodiversitylibrary.org ↩︎In 6 volumes, it gives botanical descriptions and some uses of the plants. It can be downloaded from the Internet.
[7]West African Forests and Forestry — Unwin A.H. · T. Fisher Unwin Ltd.; London · 1920 · http://www.biodiversitylibrary.org ↩︎Quite extensive information on some of the trees of West Africa. The book can be downloaded from the Internet
[PFAF]Plants for a Future — pfaf.org ↩︎