Dioscorea L.


Commemorating Dioscorides, an ancient Greek physician and naturalist (fl. 50–70 AD).

Tuberous twining herb occasionally with axillary bulbils (yams). Leaves mostly simple and alternate. Male flowers with 6 stamens in 2 whorls, the inner whorl sometimes infertile. Female flowers with a 3-chambered ovary. Fruit a papery 3-lobed capsule containing flat, winged seeds.

Division of rootstock, aerial tubers or seed.

In the tropics the edible tubers of several species of yams are grown as a source of carbohydrate (a few species are poisonous). A valued plant of indigenous cultures. Important species include D. batatas, Chinese Yam, D. bulbifera, Air Potato from Asia, the intriguing Elephant's Foot, D. elephantipes from South Africa, D. esculenta, Potato Yam, from East Asia, and D. trifida, Cush-cush or Yampee from tropical America. Also a source of corticosteroids used as anti-inflammatories, and diosgenin, a precursor of progesterone which is used in oral contraceptives.

Twining plants with insignificant green flowers, mostly opposite leaves, tuberous roots (yams) and capsular fruit.

About 630 species from the tropics and warm areas.

Source: Spencer, R. (2005). Dioscoreaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Lilianae
order      Dioscoreales
family       Dioscoreaceae
Higher taxa
Subordinate taxa