Water Yam
Dioscorea alata – also called ube, ubi, uwhi, purple yam, or greater yam, among many other names – is a species of yam. The tubers are usually a vivid violet-purple to bright lavender, but some range from creamy-white to plain white. Although it is sometimes confused with taro and the Okinawa sweet potato beniimo , D. alata is also grown in Okinawa. Its origins are in the Asian and Oceanian tropics. Some varieties attain to great size. A "Mambatap" greater yam grown in Maprik, East Sepik District, Papua New Guinea around 1939 was 3.5 m (11 ft) in length.
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Research Mentions
Unveiling the Nutraceutical Potential of Yam Dioscorea alata L.: A ...
That purple yam you might grow as an ornamental or edible in a warm-climate garden turns out to p...