Multi-purpose cowpea inoculation for improved yields in small holder farms in Kenya

Introduction In Kenya, cowpea is the most important pulse crop in the dry lands of Eastern and Coastal regions where it is commonly inter cropped with maize and sorghum. The poor yields obtained in small holder farms in Kenya (150 kg ha-1) can in part be attributed to the use of poor yielding varieties, low soil fertility (mainly N and P deficiency) low presence of effective indigenous rhizobia and high occurrence of highly competitive but inefficient indigenous rhizobia strains. Biological nitrogen fixation (BNF) through exploitation of the rhizobia-legume symbiosis and use of inoculants coupled with soil amendments such as Phosphorus offers in part a means to improve cowpea yield, nutrition and soil fertility.