Bambara Groundnut

Bambara groundnut is grown chiefly for its seed, which develops underground and is eaten fresh or dried, boiled, roasted, or ground into flour. It is an important subsistence and food-security crop across the drier parts of sub-Saharan Africa and is grown to a lesser extent in parts of Asia and South America.

As a hardy, largely landrace-based crop, it is often grown by women farmers on marginal land and provides a reliable food source in seasons and soils that are unfavorable to other crops.

Family

Fabaceae (legume family)

Genus and species

Vigna subterranea

Growth habit

Low-growing annual forming a rosette of leaves; flowers are pushed to the soil and pods mature underground

Root system

Taproot bearing nodules that host nitrogen-fixing rhizobia

Bambara groundnut is native to West Africa, where its wild relatives occur and where it was domesticated, and it has since spread across sub-Saharan Africa and to parts of Asia and the Americas. It remains predominantly a smallholder crop.

Comprehensive statistics on planted area and production are limited because much of the crop is grown for subsistence; available figures are compiled by FAO and national agencies and should be consulted directly.

Bambara groundnut is a hot-climate crop requiring warm temperatures throughout its cycle and is sensitive to frost. It is notably drought-tolerant once established and can set a crop in seasons of limited or erratic rainfall.

Some landraces are photoperiod-sensitive, and adaptation is often specific to the local environment, so locally adapted material is important for reliable performance.

Bambara groundnut grows best on light, well-drained sandy and sandy-loam soils, which suit the underground development of its pods and reduce the risk of rot. It tolerates low fertility but, like related crops, is sensitive to waterlogging.

Bambara groundnut is direct-seeded at the onset of the rains, often as a sole crop or intercropped with cereals. Earthing up or light cultivation around the plants can support pod development, and weed control is important during early growth.

• Locally adapted landrace or cultivar matched to season length and climate
• Sowing into loose, well-drained soil suited to underground pod formation
• Weed control and, in some systems, light earthing up around plants
• Rhizobial associations that in many soils establish with native rhizobia

Bambara groundnut fixes nitrogen through nodulation, often with native rhizobia, and is adapted to soils of low fertility. Phosphorus and, in some soils, calcium and other nutrients influence pod filling and yield.

Bambara groundnut is grown almost entirely under rain-fed conditions, where its drought tolerance is a key advantage. Moisture during flowering and pod filling supports yield, but the crop can produce a harvest under water-limited conditions that would fail more demanding crops.

Bambara groundnut is relatively hardy, but leaf spots, powdery mildew, and Fusarium wilt affect the crop under favorable conditions, and pod and root rots can occur on poorly drained soils. Storage pests damage dry seed.

Aphids and other sap-feeding insects, along with thrips, are among the field pests. Management relies mainly on healthy seed, rotation, field sanitation, and locally adapted material, with authorized controls used according to their labels where warranted.

Because pods mature underground, bambara groundnut is harvested by lifting or pulling whole plants, usually by hand, once the foliage begins to senesce. Fresh pods are dug earlier for immediate cooking, while seed for storage is dried thoroughly.

• Fresh seed boiled and eaten as a vegetable in the early season
• Dried seed boiled, roasted, or ground into flour for a range of dishes
• A nutritionally balanced pulse combining protein and carbohydrate
• Residues used as livestock fodder; crop contributes fixed nitrogen to soils