|Purple yam at Maui, Hawaii|
|Purple yam tuber|
Dioscorea alata, known as purple yam and many other names, is a species of yam, a tuberous root vegetable. The tubers are usually bright lavender in color, hence the common name, but they may sometimes be white. It is sometimes confused with taro and the Okinawa sweet potato (Ipomoea batatas cv. Ayamurasaki), although D. alata is also grown in Okinawa where it is known as beniimo (紅芋?). With its origins in the Asian tropics, D. alata has been known to humans since ancient times.
Because it has become naturalized throughout tropical South America, Africa, Australia, the US southeast, D. alata has many different common names from these regions. In English alone, aside from purple yam, other common names include greater yam, Guyana arrowroot, ten-months yam, water yam, white yam, winged yam, or simply yam. In other cultures and languages it is known variously as ratalu or violet yam in India, rasa valli kilangu (இராசவள்ளிக்கிழங்கு) in Tamil, dandila (දන්දිල) in Sinhala, thuppa genasu (ತುಪ್ಪ ಗೆಣಸು) in Kannada, thoona or soona kerungu (ತೂ/ಸೂಣ ಕೆರುಂಗು) in Tulu, kondfal (कोंदफळ) in Marathi, kachil (കാച്ചില്) in Malayalam, and khoai mỡ in Vietnam. For the Igbo people of southern Nigeria, it is called ji or ji abana; while for the Yoruba people of the southwestern Nigeria, it is called isu ewura.
*qube / *ʔube can be reconstructed as the Proto-Malayo-Polynesian word for D. alata, and words descended from it are found throughout the geographic range of this widespread language family, though in some daughter languages they are generalized or transferred to other root crops. Examples include Tagalog and Visayan ube or ubi, Indonesian and Malay ubi**, Malagasy ovy**, Fijian uvi, Tongan ʻufi, Samoan ufi**, as well as Māori and Hawaiian uhi. D. alata was one of the canoe plants that the Polynesians brought with them when they settled new islands.
** Not specific to D.alata
Purple yam is used in a variety of desserts, as well as a flavor for ice cream, milk, Swiss rolls, tarts, cookies, cakes, and other pastries. In the Philippines, it is known as ube and is often eaten boiled or as a sweetened jam called ube halayá; the latter is a popular ingredient in the iced dessert called halo-halo. In Maharashtra, the stir-fried chips are eaten during religious fasting. Purple yam is an essential ingredient in Undhiyu. Purple yam is a popular dessert in Jaffna, Sri Lanka.
Ube is now making a scene in the American foodie trend. It is now being used to make ube truffles, ube leche flan cupcakes and ube donuts. Examples can be found at Cafe 86 (Southern California) and Manila Social Club in New York.
D. alata is sometimes grown in gardens for its ornamental value.
Dioscorea alata is native to Southeast Asia (Indochina, Philippines, Indonesia, etc.) and surrounding areas (Taiwan, Ryukyu Islands, Assam, Nepal, New Guinea, Christmas Island). It has escaped into the wild in many other places, becoming naturalized in parts of China, Africa, Madagascar, the Western Hemisphere, and various islands in the Indian and Pacific Oceans. It persists in the wild in the United States in Louisiana, Georgia, Alabama, Florida, Puerto Rico, Haiti, and the U.S. Virgin Islands. It is considered an invasive species, at least in Florida.
- Dioscorea alata was first described and published in Species Plantarum 2: 1033. 1753. "Name - Dioscorea alata L.". Tropicos. Saint Louis, Missouri: Missouri Botanical Garden. Retrieved May 26, 2011.
- "The Plant List: A Working List of All Plant Species".
- GRIN (May 9, 2011). "Dioscorea alata information from NPGS/GRIN". Taxonomy for Plants. National Germplasm Resources Laboratory, Beltsville, Maryland: USDA, ARS, National Genetic Resources Program. Retrieved May 26, 2011.
- Samuel Oluwole Ogundele (2007). "Understanding aspects of Yoruba gastronomic culture". Indian Journal of Traditional Knowledge. 6: 50–56.
- Blust, Robert (2010). Trussel, Stephen, ed. "Austronesian Comparative Dictionary, web edition: *qubi yam: Dioscorea alata Linn.". http://www.trussel2.com/ACD. Retrieved 23 August 2013. External link in
- Degras, L. 1993. The Yam: A Tropical Root Crop. London, New York, and Wageningen
- James A. Duke. "Dioscorea alata (DIOSCOREACEAE)". Dr. Duke's Phytochemical and Ethnobotanical Databases. Retrieved May 26, 2011.
- Moriya C, Hosoya T, Agawa S, Sugiyama Y, Kozone I, Shin-Ya K (2015). "New acylated anthocyanins from purple yam and their antioxidant activity.". Biosci Biotechnol Biochem. 79 (9): 1484–92. doi:10.1080/09168451.2015.1027652. PMID 25848974.
- Jinwei Li, Lianfu Zhang, and Yuanfa Liu (2013) "Optimization of Extraction of Natural Pigment from Purple Sweet Potato by Response Surface Methodology and Its Stability" Journal of Chemistry, volume 2013, article ID 590512, 5 pages doi:10.1155/2013/590512
- Kew World Checklist of Selected Plant Families
- Flora of China, Vol. 24 Page 296, 参薯 shen shu, Dioscorea alata Linnaeus, Sp. Pl. 2: 1033. 1753.
- Smith, A.C. (1979). Flora Vitiensis Nova. A new flora for Fiji (Spermatophytes only) 1: 1-495. Pacific Tropical Botanical Garden, Lawai.
- Brunel, J.F., Hiepo, P. & Scholz, H. (eds.) (1984). Flore Analytique du Togo Phanérogames: 1-751. GTZ, Eschborn.
- Morat, P. & Veillon, J.-M. (1985). Contributions à la conaissance de la végétation et de la flore de Wallis et Futuna. Bulletin du Muséum National d'Histoire Naturelle. Section B, Adansonia 7: 259-329.
- Boudet, G., Lebrun, J.P. & Demange, R. (1986). Catalogue des plantes vasculaires du Mali: 1-465. Etudes d'Elevage et de Médecine Vétérinaire des Pays Tropicaux.
- George, A.S., Orchard, A.E. & Hewson, H.J. (eds.) (1993). Oceanic islands 2. Flora of Australia 50: 1-606. Australian Government Publishing Service, Canberra.
- Acevedo-Rodríguez, P. & Strong, M.T. (2005). Monocotyledons and Gymnosperms of Puerto Rico and the Virgin Islands. Contributions from the United States National Herbarium 52: 1-415.
- Tanaka, N., Koyama, T. & Murata, J. (2005). The flowering plants of Mt. Popa, central Myanmar - Results of Myanmar-Japanese joint expeditions, 2000-2004. Makinoa 5: 1-102.
- Akoègninou, A., van der Burg, W.J. & van der Maesen, L.J.G. (eds.) (2006). Flore Analytique du Bénin: 1-1034. Backhuys Publishers.
- Catarino, L., Sampaio Martins, E., Pinto-Basto, M.F. & Diniz, M.A. (2006). Plantas Vasculares e Briófitos da Guiné-Bissau: 1-298. Instituto de investigação científica tropical, Instituto Português de apoio ao desenvolvimento.
- National Parks Board Singapore (2006). Vascular Plant Life Checklist Pulau Ubin. www.nparks.gov.sg/nparks_cms/cms/cmsmgr/data/6/PlantChkList.xls.
- Sosef, M.S.M. & al. (2006). Check-list des plantes vasculaires du Gabon. Scripta Botanica Belgica 35: 1-438.
- Samanta, A.K. (2006). The genus Dioscorea L. in Darjeeling and Sikkim Himalayas - a census. Journal of Economic and Taxonomic Botany 30: 555-563.
- Pandey, R.P. & Dilwakar, P.G. (2008). An integrated check-list flora of Andaman and Nicobar islands, India. Journal of Economic and Taxonomic Botany 32: 403-500.
- Wilkin, P. & Thapyai, C. (2009). Flora of Thailand 10(1): 1-140. The Forest Herbarium, National Park, Wildlife and Plant Conservation Department, Bangkok.
- Demissew, S. & Nordal, I. (2010). Aloes and other Lilies of Ethiopia and Eritrea , ed, 2: 1-351. Shama Books, Addis Ababa, Ethiopia.
- "Profile for Dioscorea alata (water yam)". PLANTS Database. USDA, NRCS. Retrieved May 26, 2011.
- Biota of North America Program, 2013 county distribution map
|Wikimedia Commons has media related to Dioscorea alata.|
|Wikispecies has information related to: Dioscorea alata|