Evaluating Yam-Based Cropping Systems Using Herbaceous Leguminous Plants in the Savannah Transitional Agroecological Zone of Benin

Traditional yam cropping systems are based on shifting cultivation and slash and burn which lead to deforestation and soil degradation. The objective of this study was to determine the productivity of cropping sequences with herbaceous legumes and their effects on the profitability of subsequent yam. We compared smallholders' traditional cropping sequences (one-year fallow of Andropogonon gayanus, maize) with those using herbaceous legumes (maize-Aeschynomene histrix, maize-Mucuna pruriens var utilis) during 2002-2005. Highest dry mater, nutrients recycled, and net nitrogen contribution were found with Mucuna preceding yam (P < 0.001). Highest net revenue and return on investment were achieved in yam-based with legumes.