Three Seasons of Subsistence Insect-Resistant Maize in South Africa: Have Smallholders Benefited?

Abstract

White maize is the staple food of the majority of the South African population. We examine if smallholder farmers that adopted insect-resistant (Bt) varieties of white maize benefited from planting Bt over the last three seasons. Commercial farmers are known to benefit from planting Bt maize in high stalk borer or corn borer infestation years, but when planted in locations or years when stalk borers are not a problem, Bt will usually not be profitable because of higher seed costs. In the first two production seasons, small farmers enjoyed higher yields with Bt maize than with conventional hybrid varieties despite lower-than-normal (yet still significant) stalk borer pressure and less-than-ideal maize production conditions. Yield is expressed according to grain per kilogram of seed planted, as seeding rates per land area differ drastically between small-scale farmers. The value of the yield benefit depended on how the farmer utilized the additional grain, with the highest valued use being home grinding and consumption substituting for more expensive store purchases. In the third season, which was also the fourth consecutive drier-than-usual season, the stalk borer infestation level was very low, and farmers who planted Bt maize had yields similar to farmers who planted conventional hybrids.