Yam is a herbaceous and edible plant that forms the Dioscorea genus, from the Discoreaceae family (Dioscoreaceae), native and common to tropical and subtropical regions around the world.
The Dioscorea genus is very broad, the most outstanding species are the Dioscorea alata (large yam or water yam) native to South Asia, Dioscorea cayenensis (yellow yam) and Dioscorea rotundata (white yam) in West Africa and the Dioscorea trifida (Mapuey) native to Tropical America.
The yam belongs to the class of plants that, when growing, store edible material in the root, corma or underground tuber, this class is well known as roots and tubers. Yam is a tuber that is widely used for food, it is of great importance in the daily diet of many peoples of the world.
This plant is characterized by green and flimsy, fickle stems, 3 to 4 m long and quadrangular and winged, large and heart-shaped leaves, small white, greenish-yellow or green flowers in axillary spikes or in clusters, and roots large and tubercular. Depending on the variety, it s or meat can be white, yellow, purple or pink, and skin from whitish to dark chocolate. Its texture can vary from smooth and moist to rough, dry and floury.
This root and tuber crop should be planted in low-lying regions, with rainfall conditions between 1,200 mm and 1,300 mm annually, and distributed throughout the year. Temperatures between 18 ºC and 34 ºC are required, and its soil must be fertile, deep, loose, without stones and with good water drainage.
The harvest is carried out 7-9 months after sowing, the foliage begins to dry, the tuber is ripe when it presents its characteristic color (it depends on the variety it is). It is important to avoid long exposure of the tubers to the sun, as they deteriorate.
Yam is a food rich in carbohydrates, proteins and an appreciable amount of vitamin C and vitamin B1. It supplies a substantial part of the needs of manganese and phosphorus in adults and, to a lesser extent, also copper and magnesium. It is usually eaten boiled, roasted or pureed.
In addition to its widespread use in food, medicinal values such as anti-inflammatory and anti-spasmodic and others are attributed due to its moderate content of alkaloids and steroids.
