lead: Plant Biotechnology, CropLife SA
South African producers, both commercial and smallholders, enjoy the benefits of having access to premium plant genetics and seed technologies. This is in part thanks to a functional regulatory framework that facilitates the registration and protection of new seed varieties, including the rigorous assessment and commercial release of traited seed technologies.
Since the implementation of the Genetically Modified Organisms Act 1997 (Act No 15 of 1997), also called the GMO Act, regulatory approvals have been granted for a total of 33 biotech traits and trait combinations for commercial cultivation in maize, soybeans, and cotton.
Access and early adoption of traited seed technology by local producers have positively contributed to the production of maize yields over the last two decades. According to Grain SA production statistics, the average yield gains doubled from 2,5 t/ha at the start of the century to more than 5 t/ha today. This sustained increase in maize productivity in South Africa is in stark contrast to maize harvests in the rest of Southern African countries, where productivity levels continue to lag behind. Considering that maize is an important staple food for the region, food security and stability remain vulnerable to increasing risks of adverse weather conditions and climate events.
Benefitting through responsible use
After more than 20 years of traited seed technology adoption, insect resistance and herbicide tolerance traits still dominate the biotech cultivation landscape in South Africa. To maximise their return on investment with this seed technology, producers are required to implement appropriate stewardship measures to preserve the effectiveness of the technology and its benefits.
Herbicide resistance traits that are commercially available include crops carrying a bacterial gene that confers resistance to applications of the broad-spectrum herbicide, glyphosate. Herbicide-tolerant (HT) technology is a valuable option for producers in terms of weed management and is also a practical option to free up resources that would otherwise be required for manual weeding, especially within a smallholder farming context. However, the planting of HT crops is not a quick fix for weed control in the field. The primary goal for weed control is always to combine as many weed management practices as possible, to sufficiently reduce selection pressure for the development of resistance. This means integrating good agricultural practices with a combination of applicable weed management strategies to optimise the benefits derived from HT crop cultivation.
Commercially available insect resistance traits expressing single or stacked insecticidal proteins (known as Bt) within crops, provide effective control against targeted pests such as maize stem borer (Busseola fusca) and African cotton bollworm (Helicoverpa armigera). The development of resistance by target pests remains a priority for sustainable use of this technology, as producers sometimes fail to see the value of integrating the technology as part of a broader pest management approach at farm level. Producers are therefore urged to deploy good agricultural practices, including resistance management strategies that prioritise the mandatory planting of refuge areas and the selection of varieties with stacked insect-resistant (IR) traits that offer a better level of targeted pest management and further delay resistance.
Both IR and HT seed technologies have become an integral part of mainstream agriculture, offering producers an important tool in the fight against targeted weeds and insect pests. Apart from protecting yields and safeguarding food security, these technologies have also offered distinct benefits by enabling producers to engage in agricultural production that is more sustainable and compatible with the environment.
Promoting sustainable agricultural production practices
The widescale adoption of biotech crops, both in South Africa and elsewhere, has significantly moderated the environmental footprint of modern farming practices while contributing to the sustainable production of safe and affordable food.
Published reviews on the impact of GMO cultivation over a 25-year period have demonstrated that the adoption of the technology globally has made a positive impact on agriculture’s environmental footprint in the following ways:
- Increased crop productivity was achieved due to better control of target pests and weeds, resulting in improved farm income for all users of the technology.
- Supported biodiversity conservation was the result of increased productivity that was achieved without the need for expansion of farmland or cultivation in protected areas.
- It improved the environmental footprint of modern agriculture by reducing the need for crop protection product applications.
- The adoption of no-till farming practices was promoted, thereby ensuring less disturbance to the soil and reduced emissions from farm equipment.
- By ensuring the adoption of sustainable on-farm practices, the technology has helped climate mitigation efforts.
- It has improved food security outcomes and the livelihoods of producers.
Global discussions regarding the protection of the environment and its natural resources continue to take centre stage, with global leaders and governments negotiating targets aimed at reversing biodiversity loss and mitigating climate change. As they deliberate on the best outcomes to sustainably feed the world, protect the planet and mitigate climate change, they must also consider how science-based innovation and technology continue to positively contribute to these global challenges.
The adoption of biotech seed varieties by producers locally and elsewhere has proven its value and demonstrated how the responsible and appropriate integration of innovative technologies can make a difference and offer sustainable solutions towards transforming the agri food system and help to achieve sustainability goals.
Source
Brookes, G. 2022. ‘Genetically Modified (GM) Crop Use 1996–2020: Impacts on Carbon Emissions’, GM Crops & Food, 13(1), pp. 242–261. doi: 10.1080/21645698.2022.2118495.
