Report on genetically modified maize released

Initiated by the Department of Environmental Affairs and coordinated by the South African National Biodiversity Institute (SANBI) and the Directorate of Nature Management (DN) in Norway, its project partners included the Centre for Biosafety (GenØk) in Norway and the North-West University, University of Fort Hare and University of the Free State.

Monitoring insect resistant maize

The project has resulted in the development of a framework for environmental monitoring of insect resistant maize. It represents the first ever project of its kind in South Africa, and has brought to the fore a number of interesting findings regarding the deployment of genetically modified organisms (GMOs) into the South African environment.

While the framework for GM maize is of direct relevance to the monitoring of insect resistant maize, it also represents a blueprint for research and monitoring for other GM crops in South Africa. This will go a long way towards strengthening and supporting the regulatory framework governing GMOs in the country, and will contribute to the responsible and sustainable use of this technology in meeting national imperatives.

Previously, pest control on maize was managed with wide scale pesticide usage, however pesticides were found to have adverse effects on the environment and human well being. The development of modern biotechnology provided an alternative, and led to the development of a genetically modified maize with a transgene from Bacillus thuringiensis that produces a toxin to manage a specific maize pest.

Assessing post-release risks

Globally all GM products undergo stringent risk assessments prior to commercialisation, however there exists the possibility of unintended risks occurring. These can only be identified and investigated post-commercial release. The EBCP sought to identify these post-release risks. The various aspects under investigation ranged from impact on target and non-target organisms, impact on soil organism biodiversity, as well as the impact of gene flow and its subsequent contribution to the development of insect resistance.

Outcomes

Some the key scientific research outcomes from this project, which are detailed in the report include:

• Toxin levels varied between plant tissues as well as from plant to plant. This variability in toxin production could contribute to resistance development - as insects may be exposed to sub-lethal dosages, developing an immunity
  
• Gene flow from Bt maize (Maize with the toxin) to non-Bt maize (Maize without the toxin) through cross-pollination, results in the production of low levels of Bt toxin - another potential contributor to resistance development
  
• Resistance to the toxin had previously only been detected in the Northern Cape. The EBCP found the presence of another Bt-resistant population in the North West area, suggesting a further spread of resistance into other provinces
  
• Current refugia requirements, i.e. planting a specific percentage of non-Bt maize with Bt maize will no longer suffice to manage resistance in areas where resistance has already developed.
  
• The genetic background of the maize variety used and the growing environment are important considerations in terms of study design, as varying environmental conditions have a definite impact on the plant.

The results clearly show that management strategies for GM Maize will need further investigation, and given that most of South Africa's commercial maize farmers grow Bt Maize, this has potentially wide socio-economic implications, which would be of interest to a variety of stakeholders, including consumers, industry, agriculture, as well as the scientific community.

The implications of the results include yield, production costs and pest management, all of which affect the maize market and impact on the costs of maize and maize products for the 'man on the street'.

Further developments

While one of the successes of the EBCP has been the development of a monitoring framework, there are other achievements which include a contribution to human capacity development in biosafety and an increase in biosafety knowledge, through the successful training of 11 post-graduate students. It is expected that these students will continue to pursue biosafety related research and remain in, and contribute to, the development of the sector in the future.

The EBCP also contributed to the training of 65 local and regional researchers and experts from across the Southern African region, through the hosting of a Southern African Biosafety Course. This gathering fostered national and international collaboration and research links and has led to the development of a network between institutions within South Africa and abroad.

After a stringent peer review process, the findings of the scientific component in the EBCP may be used to further guide regulators and policy makers. This research will also compliment other GMO initiatives across the country, enabling South Africa to develop a robust regulatory framework.