Bt maize presents significant economic risks and doesn’t match up to local non-GM varieties, shows a new study by university researchers

EXCERPT (from the new paper): In summary, current Bt maize varieties in South Africa are expensive, are not suited to planting in sub-optimal agricultural environments and come with regulations that smallholders do not understand or with which they do not agree. Whilst some of these problems can be remedied, there are cheaper alternatives available that are more attuned both to smallholders’ agro-ecologies and to their farming practices.

Bt maize brings minimal benefit to smallholder farmers in South Africa

THIRD WORLD NETWORK, 13 February 2015

Maize is the major staple crop in many parts of Africa. Bt maize is the only commercialised genetically modified (GM) food crop in the continent and has been cultivated in South Africa since 2001 through public and private programmes. Bt maize produces insecticidal proteins that provide resistance to the African maize stem borer (Busseola fusca) and the Chilo borer (Chilo partellus), two pests that cause significant yield losses.  

An article in the South African Journal of Science examines the efficacy of Bt maize in improving smallholder agriculture in the country (Fischer K, Van den Berg J, Mutengwa C. Is Bt maize effective in improving South African smallholder agriculture? S Afr J Sci. 2015;111(1/2), Art. #a0092, 2 pages. The article highlights the fact that Bt maize was originally developed for use in large-scale capital intensive farming, which is reflected in its functioning and currently results in it being of limited use to smallholders. It also points to the regulatory context of Bt maize in South Africa and the lack of information provided to farmers, including the need to plant a refuge of non-Bt maize next to their Bt crop to delay resistance development, which have largely prevented smallholders from benefitting from Bt maize.  

In particular, Bt maize presents significant economic risks to smallholders. Bt maize seeds cost two to five times that of non-GM hybrids and open pollinated varieties (OPVs) and the crop only performs well under optimal high-input agricultural conditions, which smallholders often cannot provide. Moreover, stem borer pressure is highly variable between seasons; therefore during years and at sites that experience low insect pressure, the economic benefit of planting Bt maize can be negative.   

Local non-GM hybrids and OPVs, on the other hand, have been found to outperform Bt maize. The authors cite positive results from public–private initiatives to develop OPVs that are tolerant to drought, low soil nitrogen and smallholders’ storage conditions as well as are resistant to major maize diseases. These features have been identified as critical to the food production and security of small farming communities in South Africa. Furthermore, OPV seeds can be saved and replanted.  

The authors conclude with a call for the South African government to invest in the further development and spread of these cheaper stress-tolerant maize OPVs to smallholders as a more sustainable alternative better suited to small-farm agro-ecology than GM crops.

The full paper can be downloaded from:

Full citation for the paper:
Fischer K, Van den Berg J, Mutengwa C. Is Bt maize effective in improving South African smallholder agriculture? S Afr J Sci. 2015;111(1/2), Art.#a0092, 2 pages.