Marnus Gouse
University of Pretoria, RSA
Jenifer Piesse
King’s College, London and University of Stellenbosch, RSA
Colin Thirtle
Imperial College London and University of Pretoria, RSA
Colin Poulton
University of London

This study uses data for the 2006/07 maize production season, for the Hlabisa, Dumbe, and Simdlangentsha districts in Kwa- Zulu-Natal, South Africa, to investigate the relative efficiencies of conventional, insect-resistant (Bt), and herbicide-tolerant (RR) maize grown by small-scale farmers. The article fits a stochastic efficiency frontier using maximum likelihood methods. The results show that both GM technologies have very little impact on efficiency and that the tillage system is an important determinant of efficiency levels. This is despite the fact that farmers who used RR seed had substantially higher yields. Higher expenditure on seed cancels out this gain in the efficiency estimates, and there is every reason to believe that these are the better farmers. Employment effects are also investigated, as the RR technology is intended to be labor saving. The results mostly serve to show how dangerous it is to make any inferences from small sample surveys in one production season.

Key words: Efficiency, genetically modified, maize, KwaZulu- Natal, smallholders, stochastic frontiers, South Africa.