Evaluation of Maize-Cowpea Intercrop Combinations for Optimum Productivity in Ebonyi State

This study evaluates different maize-cowpea intercrop combinations and row arrangements for optimising crop productivity and land use efficiency in Ebonyi State, South East Nigeria. Maize-cowpea intercropping is one of the most widely practiced farming systems in South East Nigeria, combining a high-energy cereal with a protein-rich legume to improve dietary diversity and income stability. The spatial arrangement of component crops within the intercrop significantly affects light competition, yield productivity, and nitrogen fixation benefits. This study establishes a randomised complete block design experiment at the Ebonyi State University research farm, testing four intercrop row arrangements: 2 maize rows to 1 cowpea row, 2 maize to 2 cowpea, 1 maize to 1 cowpea, and 1 maize to 2 cowpea, alongside sole maize and sole cowpea controls. TZPB maize and IT97K-499-35 cowpea are used. Grain yield of each component, land equivalent ratio, and monetary returns are computed. Findings reveal that the 2:2 maize-cowpea row arrangement achieves the highest land equivalent ratio of 1.61, indicating 61 percent greater productivity than sole crops. Monetary advantage index is highest in this arrangement. The 1:2 arrangement favours cowpea and reduces maize contribution significantly. Biological nitrogen fixation measured by nodule assessment is highest in the 1:2 arrangement. The study concludes that the 2:2 row arrangement provides the optimum balance for maize-cowpea intercrop productivity in Ebonyi State. It recommends farmer field school demonstration of this arrangement.

Keywords: maize-cowpea intercrop, row arrangement, land equivalent ratio, Ebonyi State, intercropping.