LOW-INPUT TECHNOLOGY OPTIONS FOR MILLET-BASED CROPPING SYSTEMS IN THESAHEL

Pearl millet is a staple cereal cultivated mainly by subsistence farme rs on 14 million ha of the West African semi-arid tropics. Increasing pressure on the land has reduced the length of the fallow periods, whi ch are necessary to restore soil fertility, resulting in declining yie lds. To investigate ways of reversing this decline, three systems comb ining phosphorus fertilizer application, improved varieties of millet and cowpea, and improved agronomic practices were compared with the tr aditional millet-cowpea intercrop system in a three year experiment. T he most productive system involved the rotation of fertilized millet a nd cowpea. Pre-sowing tillage increased hay and fodder yields in all t he improved systems. The application of fertilizer increased the amoun t of available phosphorus in the soil. Soil pH declined somewhat in al l treatments, although the initially low soil organic matter did not c hange.