''Dioscorea cayenensis'' subsp. ''rotundata'', commonly known as the white yam, West African yam, Guinea yam, or white ñame, is a subspecies of

yam Yam or YAM may refer to: Plants and foods *Yam (vegetable), common name for members of ''Dioscorea'' * Taro, known in Malaysia and Singapore as yam * Sweet potato, specifically its orange-fleshed cultivars, often referred to as yams in North Amer ...

native to Africa. It is one of the most important cultivated yams.USDA PLANTS profile for ''Dioscorea rotundata''
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is one of its most important cultivars. It is sometimes treated as separate species from ''

Dioscorea cayenensis ''Dioscorea cayenensis'' is a species of yam in the genus ''Dioscorea'' that is a widely consumed West African domesticated crop. ''Dioscorea rotundata ''Dioscorea cayenensis'' subsp. ''rotundata'', commonly known as the white yam, West Afric ...

''.

Domestication

Its wild progenitor is ''

Dioscorea praehensilis ''Dioscorea praehensilis'' is a species of yam in the genus ''Dioscorea'' native to Africa. It is the wild progenitor of the West African domesticated crops ''Dioscorea rotundata'' and ''Dioscorea cayennensis''. It is a liana A liana is a ...

'' and possibly also '' D. abyssinica'' (by hybridization). Domestication occurred in West Africa, along the south-facing Atlantic coast. There is insufficient documentation and insufficient research to guess how long ago that occurred.

Distribution

''D. c.'' subsp. ''rotundata'' is grown in West Africa, including countries such as

Ivory Coast Ivory Coast, also known as Côte d'Ivoire, officially the Republic of Côte d'Ivoire, is a country on the southern coast of West Africa. Its capital is Yamoussoukro, in the centre of the country, while its largest city and economic centre is ...

, Ghana and Nigeria.Biodiversity and domestication of yams in West Africa: Traditional practices leading to ''Dioscorea rotundata'' Poir.
Roland Dumont ''et al.'' 2005, CIRAD-IPGRI

Linguistics

Blench (2006) reconstructs the tentative Proto-Niger-Congo (i.e., the most recent common ancestor of the Niger-Congo languages) root -ku for ''D. rotundata''.

References

Crops originating from Africa Yams (vegetable) Flora of West Tropical Africa Plant subspecies cayenensis subsp. rotundata {{Monocot-stub