Crop yield gap and yield convergence in African countries

Raising crop yield per unit land area remains a key to eliminating food shortages given limited land resources. However, Africa still falls far behind other continents in crop yield and there is major variation across regions within Africa. This paper analyzed regional yield gaps and yield convergence in Africa for four major crops: maize, millets, sorghum, and cassava. The club convergence test was employed to test whether yields are converging in Africa. Our results found no evidence of population convergence as a whole for any of the crops. However, we found that crop yields are converging into several clubs or groups of countries, implying successful technology diffusion and use within, but not between, specific regions. Furthermore, we predicted the attainable output for the four crops based on club convergence using the highest actual yield in each club as the attainable yield for all countries in the same club, and found that the gap between actual output and attainable output is narrowing gradually. Nevertheless, actual output could still increase by 70% if all countries reached the yield frontier, which we defined as the highest actual yield in each club. We suggest that policies aiming to end hunger in Africa should focus on eliminating barriers to technology diffusion and use of agricultural support mechanisms between countries, particularly those in the same club.