''Cajanus kerstingii'' is a widely ignored

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

found mostly in open

savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

conditions across

western Africa West Africa, also known as Western Africa, is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Ma ...

. It is closely related to the widely utilised ''

Cajanus cajan The pigeon pea (''Cajanus cajan'') or toor dal is a perennial legume from the family Fabaceae native to the Eastern Hemisphere. The pigeon pea is widely cultivated in tropical and semitropical regions around the world, being commonly consumed in ...

'', otherwise known as

pigeon pea The pigeon pea (''Cajanus cajan'') or toor dal is a perennial legume from the family (biology), family Fabaceae native to the Eastern Hemisphere. The pigeon pea is widely cultivated in tropical and semitropical regions around the world, being com ...

. ''Cajanus kerstingii'' can be consumed by humans as a

cereal A cereal is a grass cultivated for its edible grain. Cereals are the world's largest crops, and are therefore staple foods. They include rice, wheat, rye, oats, barley, millet, and maize ( Corn). Edible grains from other plant families, ...

pulse In medicine, the pulse refers to the rhythmic pulsations (expansion and contraction) of an artery in response to the cardiac cycle (heartbeat). The pulse may be felt ( palpated) in any place that allows an artery to be compressed near the surfac ...

fibre Fiber (spelled fibre in British English; from ) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorp ...

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...

. Unfortunately, very little data exists for this plant, but "one may reasonably expect it to be of value".

Description

''Cajanus kerstingii'' is an erect shrub that grows to be . It is a dicot in the genus ''

Cajanus The genus ''Cajanus'' is a member of the plant family Fabaceae. There are 37 species, mainly distributed across Africa, Asia and Australasia. Species include the pigeon pea (''C. cajan''), which is a significant food crop. The natural range ...

'' of the subfamily

Faboideae The Faboideae are a subfamily of the flowering plant family Fabaceae or Leguminosae. An acceptable alternative name for the subfamily is Papilionoideae, or Papilionaceae when this group of plants is treated as a family. This subfamily is widely ...

(

Fabaceae Fabaceae () or Leguminosae,International Code of Nomen ...

). When fully harvested, ''C. kerstingii'' produces a fruit that can be consumed by humans for various nutritional purposes. In order to recognise the plant, one should seek green branches, or occasionally browny-purple. The leaves are faintly striate (marked by ridges or grooves) and a glandular punctate, meaning the glands of the leaf are sunken in, noticeable when held against the light.

History, geography, ethnography

This plant grows primarily in Western African regions, namely

Burkina Faso Burkina Faso is a landlocked country in West Africa, bordered by Mali to the northwest, Niger to the northeast, Benin to the southeast, Togo and Ghana to the south, and Ivory Coast to the southwest. It covers an area of 274,223 km2 (105,87 ...

Nigeria Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, ...

and

Ghana Ghana, officially the Republic of Ghana, is a country in West Africa. It is situated along the Gulf of Guinea and the Atlantic Ocean to the south, and shares borders with Côte d’Ivoire to the west, Burkina Faso to the north, and Togo to t ...

. Other records show its presence in more countries, such as

Benin Benin, officially the Republic of Benin, is a country in West Africa. It was formerly known as Dahomey. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the north-west, and Niger to the north-east. The majority of its po ...

Mali Mali, officially the Republic of Mali, is a landlocked country in West Africa. It is the List of African countries by area, eighth-largest country in Africa, with an area of over . The country is bordered to the north by Algeria, to the east b ...

Senegal Senegal, officially the Republic of Senegal, is the westernmost country in West Africa, situated on the Atlantic Ocean coastline. It borders Mauritania to Mauritania–Senegal border, the north, Mali to Mali–Senegal border, the east, Guinea t ...

and

Togo Togo, officially the Togolese Republic, is a country in West Africa. It is bordered by Ghana to Ghana–Togo border, the west, Benin to Benin–Togo border, the east and Burkina Faso to Burkina Faso–Togo border, the north. It is one of the le ...

. ''C. kerstingii'' thrives in open savannah conditions,

lateritic Laterite is a soil type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by intensive and prolo ...

hills, and can survive at altitudes of . Several studies have shown that it is common on hilltops or hillsides, among grasses, large granite boulders, and occasionally shrubby trees. The species was first formally described by German botanist Hermann August Theodore Harms, in 1915 from a specimen collected by Otto Kersting in Togo in 1902.

Growing conditions

''Cajanus kerstingii'' is propagated via fruit. ''Cajanus kerstingii'' is also a perennial, non-climbing shrub, meaning it survives for more than two years. Further advantages include its resistance to flames. It grows best in soil that is fine and gravel-like.

Weeds, pests, diseases

There is little data describing the pests that ''Cajanus kerstingii'' is susceptible to. Across the globe, ''

Helicoverpa armigera ''Helicoverpa armigera'' is a species of Lepidoptera in the family Noctuidae. It is known as the cotton bollworm, corn earworm, Old World (African) bollworm, or scarce bordered straw (the lattermost in the UK, where it is a migrant). The larvae ...

'' is the most commonly detrimental pest and has been known to attack species within the genus ''Cajanus''. Specifically pertaining to ''C. cajan'', the largest impediment to growth is '' Fusarium udum'', which causes

wilting Wilting is the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure in non- lignified plant cells falls towards zero, as a result of diminished water in the cells. Wilting also serves to reduce water loss, as it ...

Prevention of wider adaptation

The biggest constraint to wider use of this crop is the lack of information. Few farmers have access to useful experiences regarding ''Cajanus kerstingii''. The main constraint to the close relative ''Cajanus cajan'' is its vulnerability to a wide variety of pests and diseases.

References

{{Taxonbar, from=Q15378708 Phaseoleae Flora of West Tropical Africa Plants described in 1915