Estimating the impact of innovation systems on maize yields: the case of Iar4d in southern Africa

Markets are known to have a great potential to unlock agricultural growth in developing countries. The conventional agricultural research and development approaches used hitherto have not yielded much success in stimulating farmer participation in markets. New agricultural development approaches, such as the Integrated Agricultural Research for Development (IAR4D), view developmental challenges as multi-dimensional and as such require multi-pronged and integrated initiatives – better known as innovation systems – to overcome. Using data from IAR4D trials in Zimbabwe, Malawi and Mozambique, the study evaluates the efficacy of IAR4D in stimulating market integration and crop intensification. The impact of IAR4D on maize yield, estimated using the local average treatment effect (LATE) is significant in all the countries. Yields improved by margins ranging 107–149 kgha-1, which is quite substantial in a region where yields average around 1000kgha-1. These findings give credence to the proposition that innovation systems such as IAR4D are more effective in stimulating agricultural growth.