Productivity and Efficiency Analysis of Maize under Conservation Agriculture in Zimbabwe

This study sought to evaluate the performance of conservation agriculture (CA) technology-essentially comparing productivity and efficiency levels in maize production in CA and conventional farming. The analysis is based on a three year panel sample of smallholder farming households and employing a stochastic production frontier model compare productivity and technical efficiency between CA and conventional farming. Study results indicate that CA technology is implemented in relatively smaller plots than conventional farming (0.36ha compared to 0.85ha) but has a significant contribution to total maize production, on average 50% of output share. Output elasticities indicate positive responses for labor and seed in CA, and negative responses in conventional farming. On the other hand, there are negative responses to land and draft in CA. Fertilizer has a greater positive response in CA than in conventional farming. Overall returns to scale are similar for CA and conventional farming (0.84 and0.89 respectively). There is evidence of technical progress in CA for the three year panel period. Technical progress has been land-saving but seed and fertilizer-using in CA, while land-using and seed-saving in conventional farming. Joint frontier estimates indicate that farmers will produce 39% more in CA compared to conventional farming. Technical efficiency levels are generally the same (about 68%) for both technologies. Two-thirds of farmers achieve efficiency scores in the 60-80% range both CA and conventional farming technologies. These results show significant yield gains in CA practices and significant contributions to food production. CA is land-saving, and this is an important issue for land constrained farmers because they can still have viable food production on smaller area. But high labor demands in CA present some problems in adoption, particularly for the poorer farmers.