Tannia ( Xanthosoma sagittifolium ), illustration
|( L. ) Schott|
Inflorescences are seldom formed in culture, reproduction is mainly vegetative.
Tannia is a perennial herbaceous plant and reaches heights of 2 to 2.5 meters. The growing season lasts nine to eleven months, then the leaves dry up and harvest can be carried out. The smooth, bulbous rhizome is bottle-shaped and up to 25 cm long. The long petiole is ribbed and retracted at the base. The leaves are divided into a petiole and a leaf blade. The simple leaf blade is arrow-shaped with a heart-shaped base.
Xanthosoma sagittifolium is single sexed ( monoecious ). The inflorescence stands on a long, leafless inflorescence stem. The inflorescence typical of Araceae consists of a spathe and a piston (spadix). The white spathe is slightly larger than the spadix at 12 to 15 cm. In the piston (spadix) there are female flowers in the lower area, sterile in the middle and male flowers in the upper area. Few seeds are formed.
The number of chromosomes is 2n = 26.
Xanthosoma sagittifolium is native to tropical America and the Caribbean and is now grown throughout the tropics . It is originally found in Costa Rica, Panama, Colombia, Ecuador, Venezuela, Peru and Brazil. Spaniards and Portuguese brought Xanthosoma sagittifolium to Europe early and it was introduced to West Africa in the mid-19th century. Xanthosoma sagittifolium is of economic importance today in the Caribbean, in Central and South America, in West Africa and in the tropical regions of Asia . The largest producers (2014) are Cuba , Nicaragua and Venezuela .
Like many species of the arum family , Tannia also contains calcium oxalate in all parts of the plant , a substance that irritates the mucous membranes. The crystalline deposits are also known as crystal sand. When consumed, calcium oxalate can cause itching in the mouth and throat, and consumption can also lead to digestive disorders. In the case of Tannia, the substance is so aggressive that it can cause painful burning irritation of the mucous membranes when harvested .
When cooking, however, the substances dissolve and pass into the cooking water. Food and products made from tannia are considered to be of higher quality than those made from taro .
The rhizome tubers (tiquisque tuber) of this tropical crop are used as a starch supplier . Tannia is closely related to taro and is used similarly to taro , but is better adapted to drought. The cultivation is mostly for self-sufficiency. In addition to the species Xanthosoma sagittifolium , the two species Xanthosoma atrovirens and Xanthosoma nigrum are sometimes referred to as Tannia and used equally.
The harvest takes place around 12 months after the tubers have been planted out. Yields can reach 18 to 20 tons per hectare . The world annual harvest is estimated at four to six million tons.
In Tannia only the smaller minor tubers are used for human consumption, the main tubers are used exclusively as fodder, mostly in pig breeding. After peeling, the tubers are boiled in salted water. Because of the calcium oxalate content , the cooking water has to be changed several times. Tannia can also be prepared by grilling, baking or deep-frying and is just as versatile as potatoes. To make flour, the sliced tubers are dried in the sun. Bread and other baked goods are made from the cornstarch obtained. In addition, because of its high starch content, the tuber is suitable for making alcoholic beverages (“ fufu ” in Africa and “ poi ” in Hawaii ).
As Karibenkohl the young leaves and stems are used in the producing countries as a vegetable. Even with this preparation, the cooking water must be changed several times. Known as taioba in Brazil , the leaves are cut into small pieces after the petioles have been removed and fried in a pan with oil and onion as well as garlic and salt until they have the appearance of spinach , and then served as a side dish to meat dishes.
This species was first published in 1753 as Arum sagittifolium by Carl von Linné in Species Plantarum 2, p. 966, where it was written “sagittaefolium”. Heinrich Wilhelm Schott put the genus Xanthosoma with the species Xanthosoma sagittifolium in Meletemata Botanica , page 19 in 1832 . Xanthosoma sagittifolium was later again Frederik Michael Liebmann in Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i Kjøbenhavn , 1849, 15 by and Karl Heinrich Koch in Index Seminum [Berlin] , app. Published 2, 1854. Another synonym for Xanthosoma sagittifolium (L.) Schott is Caladium sagittifolium (L.) Vent.
In addition to Xanthosoma sagittifolium , one or more of the following species Xanthosoma atrovirens , Xanthosoma caracu , Xanthosoma nigrum and perhaps Xanthosoma violaceum are involved in all cultivars, but until the exact genetics of the varieties have been clarified, all of them will be named Xanthosoma sagittifolium .
The name "Tannia" is a modification from the Caribbean name for the food "taia". Another common name is "malanga". It is known internationally as "yautia" and " new cocoyam".
- FAO data sheet. (Section description and systematics).
- Gunther Franke (Ed.): Useful plants of the tropics and subtropics. Volume 3: Special Plant Cultivation , Ulmer, Stuttgart 1994, ISBN 3-8252-1769-8 , p. 398 f.
- Wolfgang Franke : crop science. 6th edition, Thieme, Stuttgart 1997, ISBN 978-3-13-530406-9 .
- Tropicos. Xanthosoma sagittifolium at Tropicos.org. Missouri Botanical Garden, St. Louis.
- Rafaël Govaerts (Ed.): Xanthosoma - World Checklist of Selected Plant Families of the Royal Botanic Gardens, Kew. Last accessed on June 14, 2018.
- FAO statistics .
- Alan Davidson, Helen Saberi and Tom Jaine: The Oxford companion to food. 2nd Edition, Oxford, 2006, ISBN 978-0-192-80681-9 , p. 473.
- FAO: Traditional post-harvest technology of perishable tropical staples .
- Carl von Linné: Species Plantarum 2, 1753, p. 966 scanned in at biodiversitylibrary.org.
- Alan Davidson, Helen Saberi and Tom Jaine: The Oxford companion to food. Oxford, 2006, p. 473.