Fertilization of Dioscorea rotundata with poultry manure: effects on nutrient dynamics and yield formation

Summary

Yams (Dioscorea spp.) are tropical tuber crops with high food and market values, contributing significantly to food security in West Africa. The traditional method of cultivation is without fertilizers as the first crop after clearing land from natural vegetation (e.g. forests) because of their high requirements in terms of soil fertility. However, due to increased population pressure on arable land, forests have become rare, fallow periods shorter, and long term fallowing more difficult in West Africa. Consequently, declining soil fertility is one of the major constraints to yam productivity and yam yields are thus far below the estimated potential. These problems call for the development of more integrated and sustainable yam production systems.