The common bean (Phaseolus vulgaris L.) makes an important contribution to food security, providing as much as 60% of the dietary protein in Rwanda and Burundi and about 30% in parts of eastern and southern Africa. It is highly valued because all parts of the plant are consumed: the leaves are used as a vegetable and the grains are eaten fresh or dried, whilst the haulm is fed to livestock. Although beans are grown largely for subsistence and mainly by women farmers, about 40% of the total production in eastern, central and southern Africa is marketed, at an average annual value of US$452 million. National research programmes in eastern and central Africa rate beans as the second most important food crop in the region.
