Manipulating legume/cereal mixtures to optimize the above and below ground interactions in the traditional African cropping systems

The purpose of mixing legume and cereals in the cropping systems is to optimise the use of spatial, temporal, and physical resources both above- and below ground, by maximising positive interactions (facilitation) and minimising negative ones (competition) among the components. The complex interactions in legume/cereal cropping systems such as those used by traditional farmers have received little research attention. Information from such studies is likely to provide an understanding of plant survival strategies when subjected to stress in mixtures. Current knowledge on how plants in mixtures change their biological and chemical environments and the potential benefits associated with such processes are assessed in this review.