South Africa should rethink regulations on genetically modified plants

Food security is a global priority – and it is becoming more urgent in the face of climate change, which is already affecting crop productivity. One way to improve food security is to increase crop yields.

But this is not easy. Research has shown that in the past two decades plant breeders have been unable to increase yields of staple crops at the rate at which the world’s population is growing.

New technologies are needed to achieve this rate. Over the past decade several novel technologies have been developed. These are known as New Breeding Techniques and have the potential to hugely help in growing efforts.

Genome editing is one such technique. It allows the precise editing of genomes – that is, the genetic information an organism contains. Scientists worldwide have embraced the technology. And countries that adopted New Breeding Techniques early have seen a significant increase in the development of locally relevant products. Current crops under development include ones resistant to specific diseases and insect pests, that are healthier to eat or which are tolerant of drought or heat stress.

Both small, micro and medium enterprises and the public sector in these countries have been involved in developing and using genome edited crops. This should translate to improved economic growth and employment opportunities.

Whatever approach a country chooses, it must be underpinned by regulation. This ensures a framework for the introduction of new products that benefit consumers and stimulate the bio-economy in a sustainable manner.

South Africa’s authorities have taken what we think is an unfortunate approach to regulating genome-edited plants. In October 2021 the government classified genome-edited plants as genetically modified crops. This is based on its interpretation of the definition of a genetically modified organism in a 25-year-old piece of legislation rather than on recent science-based risk analysis considerations.

As experts in plant biotechnology we fear that this regulatory approach will greatly inhibit the development of improved crops for South African farmers. It will place an unnecessary regulatory burden on bio-innovators. This will discourage local investment for in-house research and development, as well as projects in the public sector. Local entrepreneurs who aim to enhance local crops’ climate resilience or to develop speciality products for niche markets through genome editing will be thwarted by the need to raise disproportionate funding to fulfil current regulations.

A technological timeline

Crop plants are improved by generating genetic variation that leads to beneficial traits. Plant breeders traditionally achieved this by crossing different varieties of the same plant species. These approaches alter many genes; the result is that traditionally-bred plants contain both advantageous and deleterious traits. Removing disadvantageous traits before the crop can be commercialised is a costly, time-consuming process.

In the 1980s, transgenic genetic modification technologies were developed. These rely on pieces of DNA from one species being integrated into the genome of a crop. Such genetically modified (GM) plants are highly regulated internationally. In South Africa the legislation governing these plants came into force in 1999. The use of GM technology in South Africa – and other countries – has been highly successful.

For example, it has led to South Africa doubling maize productivity, making it a net exporter of this commodity. This contributes to food security and also generates foreign income, which reduces the country’s trade deficit.

But the regulations governing GM plants are onerous: only large agricultural biotechnology companies have the resources to commercialise them. This is done to the eliminate risk that GM plants containing new DNA are harmful for health or to the environment.

Because of this, all GM plants licensed for commercial use in South Africa come from a small number of international companies. Not a single locally developed product has been commercialised during the past three decades, despite South Africa being an early adopter of the technology. This hampers the development of novel crops and the improvement of traditional crops, especially for emerging and subsistence farmers in sub-Saharan Africa.

That’s why newer tools like genome editing are so exciting. They can be used to introduce genetic variation for crop improvement in a fraction of the time it would take using conventional methods. Some forms of genome editing are transgenic in nature, while others aren’t because they don’t involve the insertion of foreign DNA into a plant.

This approach mimics the effect of traditional plant breeding, but in a highly targeted manner so that only advantageous traits are introduced. For example, genome editing is being used to produce peanuts, soybean and wheat that do not produce allergens.

It’s working well. Despite the technology only being available for a decade, some crops produced using genome editing are already on the market in some countries, including soybean and tomatoes which are healthier for human consumption.

A proposed regulatory approach

Regulatory authorities around the world have taken either a process- or a product-based approach to regulating GM crop safety. A process-based approach examines how the crop was produced; a product-based approach examines the risks and benefits of the GM crop on a case-by-case basis.

We believe that a product-based approach makes most sense. This is because a process-based approach could lead to the strange situation where two identical plants are governed by very different regulations, just because they were produced by different methods. The added regulatory burden imposed by this approach will also hamper innovation in developing new crops.

Our approach would mean that any plant with extra DNA inserted into the genome would be governed as a GM plant. Plants with no extra DNA added and that are indistinguishable from conventionally bred organisms should be regulated like a conventionally produced crop.

This is the most rational way to regulate these different types of organisms, as it adheres to the principles of science-based risk analysis and good governance.

Many countries, among them Argentina, China, Japan, the US, Australia, Brazil and Nigeria, have taken this approach.

Science-based risk analysis should return to the heart of regulation: concrete risk thresholds should define regulatory triggers.

James R Lloyd, Associate Professor, Stellenbosch University; Dave Berger, Professor in Molecular Plant Pathology, University of Pretoria, and Priyen Pillay, Senior Researcher, Council for Scientific and Industrial Research

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Researchers

• 

  Professor Dave Berger

  Professor Dave Berger has been a researcher at the University of Pretoria’s (UP) Forestry and Agricultural Biotechnology Institute (FABI) since 2000. He obtained his undergraduate degree and a PhD in Microbiology from the University of Cape Town.
  
  Prof Berger says UP has an excellent environment for researchers working in the general area of plant biotechnology. He attributes this to strong foundations in the plant sciences and genetics, and the critical mass of research groups and postgraduates at FABI and linked departments.
  
  “This is a multidisciplinary environment where in one student seminar session there can be conversations about diverse topics, such as gene-editing insects, the physiology of sunflowers and the countrywide surveillance of maize fungal diseases,” he says.
  
  Prof Berger leads the Molecular Plant-Pathogen Interactions research group at FABI. His research is focused on leaf diseases of a staple crop, maize. “My ‘model’ pathosystem is grey leaf spot disease, which is caused by the fungus Cercospora zeina. The disease is widespread globally, but is a particular threat to smallholder farmers in sub-Saharan Africa. My research group aims to understand both Cercospora pathogenicity and maize host resistance at the molecular level.”
  
  As to how his field of research contributes to improving society, Prof Berger says that crop diseases are a major threat to food security and can spread in a way that is similar to the way the SARS-CoV-2 virus circulates among people. Plant pathologists are on the frontline of monitoring the distribution and spread of crop pathogens, he adds.
  
  One such example is the fungus that Prof Berger’s research group is working on, Cercospora Zeina, which causes grey leaf spot disease throughout sub-Saharan Africa, and is also found in the Americas and Asia. Severe infections can result in a farmer losing most of their maize crop.
  
  “Our research leads to better disease control by, for example, breeding for resistance to the pathogen strains in a country, or developing novel control measures by understanding how the pathogen causes disease at the molecular level. Plant pathology research is critical to meeting the Sustainable Development Goals of zero hunger and no poverty.”
  
  Over the past 18 months, Prof Berger and his research group have completed a surveillance study of the fungal pathogen that causes grey leaf spot disease in five countries in sub-Saharan Africa. They conducted genetic analyses of 1 000 isolates to test hypotheses about the origin of the pathogen in Africa.
  
  “We concluded that it is unlikely that there was a single introduction of the pathogen into Africa. We found country-specific patterns of diversity; for example, the Zambian population was the most distinct.”
  
  Part of the project included presenting a workshop on disease identification in western Kenya for local researchers and students. Prof Berger was involved as a co-supervisor of one of the students, who completed his MSc this year at Maseno University in Kenya.
  
  Prof Berger and his team are also involved in a cross-faculty research project in which researchers are using artificial intelligence for maize disease diagnosis based on images of symptoms on maize leaves. His team is working with Prof Nelishia Pillay of the Department of Computer Science in the Faculty of Engineering, Built Environment and Information Technology.
  
  “We have also teamed up with a local company to use their app for collecting maize disease images with accurate meta-data for future use in developing digital plant pathology solutions,” he says.
  
  Prof Berger says he is inspired and excited to be a biological scientist at the time of “DNA and genomes, where technical innovations are affording us new ways to explore nature at many levels, from ecosystems to single cells”.
  
  He adds that his PhD supervisors, Prof Dave Woods and the late Prof Doug Rawlings, played seminal roles in establishing molecular biology in the South African research landscape. “They were inspiring leaders who created cohesive research environments, and they were excellent scientists in their own right.”
  
  Molecular biologists generally dream of “discovering” a novel gene or molecular mechanism which describes a biological activity for the first time. In the field of molecular plant pathology, identifying a novel plant disease resistance gene and describing its function is one of those dreams. “We have come close to identifying a maize gene that could confer basal disease resistance against grey leaf spot disease, but much work is still needed to nail this down,” he says.
  
  His research matters, Prof Berger, says because achieving food security is a major challenge to the global population. His team’s research in plant pathology is geared towards controlling crop pathogens and developing crops that can yield better on less land.
  
  “Many disease problems are region-specific and so there is a need for local expertise and trained researchers who think globally but act locally. The postgraduate and postdoctoral students in my research programme gain experience in high-tech experiments in the laboratory, but also spend time on field trips interacting with farmers. This makes them work-ready for real-world challenges.”
  
  Molecular plant pathology is best suited to people who like to work precisely in a laboratory and analyse data, Prof Berger says. “However, computer boffins can also work in the field as bioinformaticians. Their research involves exploring big data from pathogen and plant genome sequencing, and linking this to the biology of the plant disease.”
  
  His advice to learners who are interested in his field is to start building the habit of studying with discipline while still at school, and to cultivate their curiosity. “Go out into the bush: observe, measure and celebrate the natural world,” he says. “Learn to do computer programming. During your undergraduate studies, read widely, ask a lot of questions in class, search for practical experience – volunteer for lab work or fieldwork. Don’t neglect statistics, and learn how to use computer platforms such as RStudio.”
  
  In his spare time, he enjoys hiking, mountain biking, nature photography, botanising and birdwatching.

  More from this Researcher