1. Family: Fabaceae Lindl.
    1. Genus: Vigna Savi
      1. Vigna subterranea (L.) Verdc.

        Bambara groundnut ( Vigna subterranea) is an important grain legume which grows in the semi-arid regions of Africa. Its ability to fix nitrogen and its resistance to high temperatures and drought makes it a valuable crop in areas where soils are too poor for other leguminous crops to grow. By burying its fruits in the soil it protects them from insect damage which can devastate other crops such as cowpea, common bean and soybean, whose tastiest parts are above ground.

    [KSP]

    Kew Species Profiles

    General Description
    Bambara groundnut is a creeping annual legume native to the semi-arid areas of Africa and cultivated for its edible seeds. It also has a number of medicinal uses.

    Bambara groundnut ( Vigna subterranea) is an important grain legume which grows in the semi-arid regions of Africa. Its ability to fix nitrogen and its resistance to high temperatures and drought makes it a valuable crop in areas where soils are too poor for other leguminous crops to grow. By burying its fruits in the soil it protects them from insect damage which can devastate other crops such as cowpea, common bean and soybean, whose tastiest parts are above ground.

    Bambara groundnut is very nutritious, boasting a 65% carbohydrate content and an 18% protein content, making it an important addition to the diets of people who cannot afford expensive animal protein. It is considered to be a complete food and people can survive exclusively on bambara groundnut for all of their nutritional needs.

    Bambara groundnut is a lifesaver during the hungry season, the period that exists when the old crops have been eaten and the new crops have not yet been harvested. Despite all of these benefits it is a much underutilised and has the potential to be more than just a subsistence crop. Part of the problem is its stigma as a 'poor person’s crop'. 

    Species Profile

    Geography and distribution

    Bambara groundnut most likely originated in north-eastern Nigeria and northern Cameroon, where it can still be found growing wild today. It is cultivated throughout tropical Africa and to a lesser extent in the tropical parts of the Americas, Asia and Australia. 

    Habitat

    Bambara groundnut grows best in dry areas with sandy soils. It is also well suited to upland areas such as the highlands of Zambia and Zimbabwe. Bambara groundnut can produce a reasonably good yield in humid regions, although the dampness makes it susceptible to fungal diseases and the plant needs careful handling. 

    Description

    Vigna subterranea is a leafy, annual, creeping legume with glabrous (hairless) leaves supported by a petiole 5-30 cm long. Each leaf is composed of three leaflets (trifoliolate) and can be up to 11 cm long. 

    Yellow flowers are clustered 1-3 on an unbranched axis, known as a raceme. They are papilionaceous, typical of species belonging to the subfamily Papilionoideae, and resemble, for example, the pea flower. The peduncle (the stalk supporting the raceme) is up to 3 cm long, hairy and after flowering it expands and bends downwards so that the fruits develop underground.

    The ovary, which develops into the seed pod, contains 1-4 ovules. Once mature the seeds, which can be of various colours, are almost spherical and are 8-15 mm in diameter. Bambara groundnut has a deep taproot surrounded by lateral roots bearing nitrogen-fixing nodules.

    Threats and conservation

    Vigna subterranea is not considered to be threatened in the wild and its conservation status is of least concern (LC). 

    Uses

    Bambara groundnut is cultivated mainly for its seeds which can be boiled, roasted or fried to make a delicious snack or mixed in with maize or plantains to serve as a meal. The seeds can be ground into flour after roasting and used to prepare porridge or they can be soaked, boiled and ground into a paste and used in fried or steamed dishes popularly eaten in Nigeria. The flour can also be used as a thickener in soups and stews and in Zambia it is commonly made into bread. Milk can be made from the seeds and fermented products similar to tempeh and dawadawa can be prepared.

    Besides being a food crop, the seeds and leafy shoots of bambara groundnut, which are rich in protein and phosphorus make good fodder for pigs and poultry.

    Bambara groundnut also has a number of medicinal uses. In Senegal: 

    • leaf preparations are applied as a poultice for infected wounds and abscesses
    • leaf sap is applied to the eyes as a treatment for epilepsy
    • pounded seeds mixed with water are used to treat cataracts
    • the roots of the plant can be taken as an aphrodisiac

    Evidence suggests that high fibre foods such as bambara groundnut can reduce the incidence of heart disease and help to prevent colon cancer.

    Bambara groundnut improves the quality of the soil because of its ability to fix nitrogen from the air. It is therefore a good companion in crop rotations.

    Crop wild relatives of bambara groundnut

    The Millennium Seed Bank and the Global Crop Diversity Trust are engaged in a ten-year project, called 'Adapting Agriculture to Climate Change'. The project aims to protect, collect and prepare the wild relatives of 29 key food crops, including bambara groundnut, so that they are available to pre-breeders for the development of new varieties that are more resilient to the effects of climate change.

    Its ability to fix nitrogen and its resistance to high temperatures and drought makes bambara groundnut a valuable crop with enormous potential to be grown on a larger scale, providing food security for many more people. 

    Millennium Seed Bank: Seed storage

    The  Millennium Seed Bank Partnership aims to save plants worldwide, focusing on those plants which are under threat and those which are of most use in the future. Once seeds have been collected they are dried, packaged and stored at -20°C in Kew’s Millennium Seed Bank vault.

    Description of seeds: Average weight of 1,000 seeds = 585 gNumber of seed collections stored in the Millennium Seed Bank: OneSeed storage behaviour: Orthodox (the seeds of this plant can be dried to a low moisture content without significantly reducing their viability. This means they are suitable for long-term frozen storage)Germination testing: Successful

    This species at Kew

    Pressed and dried specimens of bambara groundnut are held in Kew's Herbarium, where they are available to researchers by appointment. Details and images of some of these specimens can be seen online in Kew's Herbarium Catalogue.

    Distribution
    Cameroon, Niger
    Ecology
    Bambara groundnut grows best in dry areas with sandy soils. More information below.
    Conservation
    Common in the wild and in cultivation and thus not globally threatened.
    [KSP]
    Use
    Food, fodder, medicine.

    Images

    Distribution

    Found In:

    Cameroon, Central African Repu, Chad, Nigeria, Sudan

    Introduced Into:

    Angola, Benin, Burkina, Dominican Republic, Ethiopia, Gambia, Ghana, Guinea, Guinea-Bissau, India, Ivory Coast, Jawa, Kenya, Madagascar, Mali, Mozambique, Namibia, New Guinea, Senegal, Sierra Leone, Swaziland, Tanzania, Togo, Uganda, Zambia, Zaïre

    Common Names

    English
    Bambara groundnut

    Vigna subterranea (L.) Verdc. appears in other Kew resources:

    Date Identified Reference Herbarium Specimen Type Status
    Dalziel, J.M. [s.n.], Nigeria K000263432 syntype
    Dalziel, J.M. [s.n.], Nigeria K000263433

    First published in Kew Bull. 35: 474 (1980)

    Accepted in:

    • [1] Darbyshire, I., Kordofani, M., Farag, I., Candiga, R. & Pickering, H. (eds.) (2015) The Plants of Sudan and South Sudan . Kew publishing, Royal Botanic Gardens, Kew.
    • [7] Akoègninou, A., van der Burg, W.J. & van der Maesen, L.J.G. (eds.) (2006) Flore Analytique du Bénin . Backhuys Publishers.
    • [10] Catarino, L., Sampaio Martins, E., Pinto-Basto, M.F. & Diniz, M.A. (2006) Plantas Vasculares e Briófitos da Guiné-Bissau . Instituto de investigação científica tropical, Instituto Português de apoio ao desenvolvimento.
    • [13] Kumar, S. & Sane, P.V. (2003) Legumes of South Asia. A Checklist . Royal Botanic Gardens, Kew.
    • [18] Lebrun, J.p., Toutain, B., Gaston, A. & Boudet, G. (1991) Catalogue des Plantes Vasculaires du Burkina Faso . Institut d' Elevage et de Médecine Vétérinaire des Pays Tropicaux, Maisons Alfort.
    • [21] Boudet, G., Lebrun, J.P. & Demange, R. (1986) Catalogue des plantes vasculaires du Mali . Etudes d'Elevage et de Médecine Vétérinaire des Pays Tropicaux.
    • [23] Brunel, J.F., Hiepo, P. & Scholz, H. (eds.) (1984) Flore Analytique du Togo Phanérogames: 1-751. GTZ, Eschborn.

    Literature

    • [2] (2012) Smithsonian Contributions to Botany 98: 1-1192
    • [3] Beentje, H. (2010). The Kew Plant Glossary: an Illustrated Dictionary of Plant Terms. Royal Botanic Gardens, Kew.
    • [4] (2008) Strelitzia 22: 1-279. National Botanical Institute, Pretoria.
    • [5] Mabberley, D.J. (2008). Mabberley’s Plant-book: a Portable Dictionary of Plants, their Classification and Uses. Third edition. Cambridge University Press, Cambridge.
    • [6] Royal Botanic Gardens, Kew (2008). Seed Information Database (SID). Version 7.1.
    • [8] Akoègninou, A., van der Burg, W.J. & van der Maesen, L.J.G. (eds.) (2006) Flore Analytique du Bénin . Backhuys Publishers.
    • [9] Brink, M. & Belay, G. (2006). Cereals and Pulses: Volume 1 of Plant Resources of Tropical Africa. PROTA.
    • [11] Catarino, L., Sampaio Martins, E., Pinto-Basto, M.F. & Diniz, M.A. (2006) Plantas Vasculares e Briófitos da Guiné-Bissau . Instituto de investigação científica tropical, Instituto Português de apoio ao desenvolvimento.
    • [12] Lock, J.M. & Ford, C.S. (2004) Legumes of Malesia a Check-List . Royal Botanic Gardens, Kew.
    • [14] Kumar, S. & Sane, P.V. (2003) Legumes of South Asia. A Checklist . Royal Botanic Gardens, Kew.
    • [15] Du Puy, D.J., Labat, N.-N., Rabevohitra, R., Villiers, J.-F., Bosser, J. & Moat, J. (2002) The Leguminosae of Madagascar . Royal Botanic Gardens, Kew.
    • [16] (2001) Flora Zambesiaca 3(5): 1-261. Royal Botanic Gardens, Kew.
    • [17] Jones, M. (1991) A checklist of Gambian plants . Michael Jones, The Gambia College.
    • [19] Lebrun, J.p., Toutain, B., Gaston, A. & Boudet, G. (1991) Catalogue des Plantes Vasculaires du Burkina Faso . Institut d' Elevage et de Médecine Vétérinaire des Pays Tropicaux, Maisons Alfort.
    • [20] Lock, J.M. (1989) Legumes of Africa a check-list . Royal Botanic Gardens, Kew.
    • [22] Boudet, G., Lebrun, J.P. & Demange, R. (1986) Catalogue des plantes vasculaires du Mali . Etudes d'Elevage et de Médecine Vétérinaire des Pays Tropicaux.
    • [24] Brunel, J.F., Hiepo, P. & Scholz, H. (eds.) (1984) Flore Analytique du Togo Phanérogames: 1-751. GTZ, Eschborn.
    • [25] Berhaut, J. (1976) Flore illustrée du Sénégal 5: 1-658. Gouvernement du Sénégal, Ministère du développement rural direction des eaux et forêta, Dakar.
    • [26] Lebrun, J.-P., Audru, J., Gaston, A. & Mosnier, M. (1972) Catalogue des Plantes Vasculaires du Tchad Méridional . Institut d' Elevage et de Médecine Vétérinaire des Pays Tropicaux, Maisons Alfort.

    Sources

    International Plant Names Index
    The International Plant Names Index (2016). Published on the Internet http://www.ipni.org
    [A] © Copyright 2016 International Plant Names Index. https://creativecommons.org/licenses/by/3.0

    Kew Species Profiles
    Kew Species Profiles
    [B] http://creativecommons.org/licenses/by-nc-sa/3.0
    [C]

    World Checklist of Selected Plant Families
    World Checklist of Selected Plant Families(2016). Published on the Internet http://apps.kew.org/wcsp/
    [D] See http://kew.org/about-kew/website-information/legal-notices/index.htm You may use data on these Terms and Conditions and on further condition that: The data is not used for commercial purposes; You may copy and retain data solely for scholarly, educational or research purposes; You may not publish our data, except for small extracts provided for illustrative purposes and duly acknowledged; You acknowledge the source of the data by the words "With the permission of the Trustees of the Royal Botanic Gardens, Kew" in a position which is reasonably prominent in view of your use of the data; Any other use of data or any other content from this website may only be made with our prior written agreement. http://creativecommons.org/licenses/by-nc-sa/3.0
    [E] © Copyright 2016 International Plant Names Index and World Checkist of Selected Plant Families. https://creativecommons.org/licenses/by/3.0