Labour savings of Roundup Ready maize: Impact on cost and input substitution for South African smallholders

This study examines the impact of genetically modified maize on labour, cost and input substitutability for smallholders in South Africa. Producers of Roundup Ready® (RR) maize use significantly less child, female and male labour than non-RR producers, resulting in lower costs despite significantly higher herbicide, seed and fertiliser costs. A treatment effects model controlling for selection bias shows that the entire cost advantage and more can be attributed to the Roundup Ready® technology. These results are supported using a nonparametric kernel density estimator. Elasticities of factor substitution indicate strong substitutability among inputs; however, a lack of statistical significance limits the interpretation of the results.