Heterogeneous and conditional returns from DT maize for farmers in Southern Africa

This paper assesses the relative advantage of drought-tolerant (DT) maize, conditional on drought severity, using an unbalanced panel of 4 years of on-farm yield trials and high-resolution precipitation data (10-day measurements at a 0.05° resolution) in Malawi, Zambia, Mozambique and Zimbabwe. Under rain-fed conditions, DT maize yield exceeds that of other varieties: 7 per cent higher yields on average and 15 per cent higher yields under moderate drought stress. While this contrasts with higher estimates measured in controlled trials, it nonetheless represents an economically significant advantage. This study further measures heterogeneity in the relative advantage conditional using conditional quantile analysis.