Cowpeas are one of the most important food legume crops in the semi-arid tropics covering Asia, Africa, southern Europe and Central and South America. A drought-tolerant and warm-weather crop, cowpeas are well-adapted to the drier regions of the tropics, where other food legumes do not perform well. It has the ability to fix atmospheric nitrogen, and grows well in poor soils with more than 85% sand and less than 0.2% organic matter and low levels of phosphorus. It is shade tolerant, and therefore, compatible as an intercrop with maize, millet, sorghum, sugarcane, and cotton. This makes cowpea an important component of traditional intercropping systems.
In Sub-Saharan Africa, cowpea is the most important grain legume crop - grown by more farmers on more farmlands (over 12 million hectares) than any other grain legume. It is mostly grown in the complex subsistence farming systems in the hot drought-prone savannas and very arid Sahelian agro-ecologies, where it is often intercropped with pearl millet and sorghum.
Cowpea is a key component in sustaining livelihoods of not only millions of farmers (the majority of whom are women), but also of hundreds of thousands of traders and local food processors. Cowpea provides not only protein-rich grain that complements staple cereal and starchy tuber crops, but also fodder for livestock, soil improvement benefits through nitrogen fixation, and households benefits from both cash and income diversity.
However, cowpea ‘on-farm’ grain yields in Sub-saharan Africa reach only 10–30% of their biological yield potential, due primarily to insect and disease attacks and drought. Improved varieties are urgently needed that will help to reduce this yield gap, taking into account existing production systems and that inputs will remain beyond the reach of resource-poor farmers.