Yam producing state in Nigeria

Nigeria produces yam in vast quantity and is accounting for about 70% of the world’s total yam production, and because of this, it is termed the largest producers of yams globally followed by Ghana and Côte d’Ivoire respectively. Yam is widely grown in the humid tropical environment and is another major staple food in Nigeria and tropical African countries.
It is mostly produce in Benue (known as the food basket of the nation), other state includes; Niger , Nassarawa, Taraba, Cross River, Adamawa, Delta, Ekiti, Imo, Edo, Kaduna, Ogun, Kwara, Ondo, Osun, Plateau, Sokoto and Oyo. 
In Nigeria, yams are produced almost in all the states of the Federation both in substantial and commercial agricultural systems and are of different species such as white yam (Dioscorea rotundata), yellow yam (Dioscorea cayenensis) and water yam. And is also used in numerous events such as traditional marriages and occasions, as a staple food and in the production of flour and others.
These species of yam in Nigeria grow better in some areas than others which is attributed mostly to the soil type; before cultivating or planting a seed yam, it is necessary that the farmland is first cleared and ploughed respectively and bear in mind that unlike other crops which might be grown from seeds, that yam is being grown from the sprout it produced.
Although it is grown widely in Nigeria, the area where it is grown most is the Benue State, which also has a (land area of 802,295 km²) one of the states in Benue valley of Nigeria where the labour-intensive practices are still the norm and the land holdings are small. In this state especially among Tiv people, the size of the yam farm or the tonnage of yams produced becomes the social status of that farmer. Because of high level of yam production in the State of Benue, Benue State is crowned as the Nigerian Bread Basket.

Yams are planted on mounds rather than flat slopes depending on the hydro orphic nature of the soils which are generally of loose soil suitable to grow roots and tuber crops. While yam production issues have been stressed on agronomical practices, a research study carried out on the economic efficiency of this crop grown in this region with small farm holdings, which is labour-intensive, reveals that land, labour and material (fertilizers and chemicals), credit and extension services inputs have a significant bearing on the yield of yam in the region.