Agroecology as a sustainable response to future challenges
When transgenic plants were first introduced around 30 years ago, they were promoted as a particularly sustainable alternative to existing farming systems, or as a solution to the problems and challenges of (conventional) agriculture. Current discussions being held on the regulation of plants derived from new genetic engineering (new GE or new genomic techniques, NGT), are once again promising almost the same 'benefits', e. g. adaptation to climate change, securing the global food supply, or a reduction in the use of fertilizers and pesticides. It is claimed that with the help of optimized 'superplants' obtained from new genetic engineering, breeding can be accelerated, food and feed quality improved and a plant-based bioeconomy advanced. This should make the agriculture of the future more productive and sustainable.
If we look at the natural adaptation processes of ecosystems to changing environmental conditions, it becomes clear that evolution does not aim for individual species to be optimally adapted. In the long run, it is not 'the fittest' that survives, but those populations and ecosystems that are diverse enough to be able to respond quickly to new challenges, such as climate change. It is, therefore, more about diversity than optimized adaptation. Against this backdrop, agroecological strategies to increase diversity in agriculture by increasing variety- and species-diversity are now well established, both practically and scientifically.
The theory of agroecology focuses on promoting positive interactions and synergies among plants, animals, soil and water. It emphasizes diversification through, for example, the cultivation of mixed crops and intercrops, agroforestry and the use of locally adapted seeds. In particular, these practices serve to improve soil structure, regulate water balance and improve animal and plant health. As a result, synthetic chemical inputs can be avoided, and diverse, resilient and productive agroecosystems can be created.
Agroecological principles also apply to forests and grasslands: mixed forests respond much more resiliently to climate change than, for example, spruce forests in monoculture. Grasslands and pastures with a wide range of species and high genetic diversity can also be significantly more resilient than those with less species diversity and low genetic variability.
The systemic approach in agroecology not only supports these ecological issues, but also many socio-economic aspects, such as the various forms of (small-scale) peasant food production, food sovereignty and the equitable distribution of resources.
In contrast to the sustainability promises of new genetic engineering, the principles of agroecology already provide appropriate answers to many current and future challenges. Practical experience shows that the nature of overall agricultural systems and the choice of crops grown, often has a much greater impact on sustainability than the breeding of individual 'superplants'. Genetic diversity within species and ecological networks is key to a wide range of possible solution approaches. Agroecology is therefore considered to have great potential with regard to a socio-ecological transformation of agricultural and food systems. The use of New GE crops, on the other hand, continues to rely primarily on the existing model of industrial agriculture, and may exacerbate the associated disadvantages for the environment and food production. Therefore, in the context of technology assessment for NGT crops, agroecology alternatives should also be considered and preferentially applied.
Conventional breeding already delivers sustainable, robust and low-risk solutions
Besides delivering higher yields and savings on fertilisers and pesticides, new genetic engineering is expected to produce plants that are better adapted to climate change. According to statements made by applicants, conventional breeding methods are very limited in their ability to produce plants with such properties, or only at considerable expense. In addition, it has been repeatedly emphasised that the introduction of NGTs will result in a considerable acceleration in plant breeding. Based on this reasoning, it is assumed that NGTs will be instrumental in achieving a more productive and sustainable future for agriculture.
A closer look at current international patent applications being filed for NGT plants that are important in sustainable agriculture and/or climate protection shows, that a great many of these patents actually describe conventional breeding methods (including random mutagenesis). Many of the plants have properties that were achieved without the use of NGTs, e. g. greater resistance to environmental influences, including resistance to bacterial infections, viruses or fungi, such as downy mildew, ‘Jordan virus’ or late blight. There are in addition a number of approaches which do not use NGTs to increase yields and improve climate-relevant properties, such as drought tolerance. The spectrum of plant species ranges from important arable crops, such as maize, rice, wheat and rapeseed, to various vegetables and fruit. These examples show that many of the advantages claimed for NGTs can be achieved using conventional methods.
In addition, some of these traits are located on so-called 'quantitative trait loci' (QTLs), i.e. several different units of genetic information within a specific chromosome segment, which are important for the expression of certain traits, such as yield or stress resistance. The exact genetic basis of these traits is often not precisely defined at the DNA level, and can be significantly influenced by the genetic background of the respective variety. Conventional breeding requires extensive genetic diversity - which is already present in the available varieties and can be increased by random mutagenesis if necessary. In contrast, NGTs can only be used to produce new traits if the precise information relevant to the DNA regions are known in advance. In many cases, it is therefore much easier to use conventional breeding methods to achieve complex traits based on QTLs.
Conventional breeding methods (including random mutagenesis) can be used to produce many of the traits which have a positive impact on sustainable agriculture and climate change mitigation. There is continuous further development of these methods yielding a whole range of interesting approaches with promising results (e.g. SMART breeding or marker-assisted selection (MAS), speed breeding or population breeding). In addition, by now it is common knowledge that future challenges such as climate change can best be met by increasing biodiversity in the fields. If, in the future, research and politics prioritise NGTs above conventional breeding, as currently proposed by the EU Commission to achieve European "Green Deal" goals and implement the "Farm-to-Fork" policy, this could slow down or even prevent urgently needed solutions that actually generate real benefits.
Under these circumstances - especially when it comes to the question of sustainability - traditional breeding methods should be given priority where there is any uncertainty, as plants (and animals) derived from conventional breeding are usually less hazardous with fewer risks than those obtained from NGTs. Alternative approaches in classical breeding should, therefore, always be considered and prioritised in the technology assessment of NGT plants. It is also important to ensure that conventionally-bred plants are not patented in order to keep access to biodiversity open for small and medium-sized breeders.