Frédéric Hénin
Whether conventional or not, plant breeding creates biodiversity. Available plant biotechnologies expedite this process. Researchers are relying on the European Commission’s proposal regarding new genomic techniques (NGTs) to have the means to create new varieties capable of withstanding abiotic and biotic stresses and improving nitrogen fixation to achieve the world’s food sovereignty and input and energy efficiency goals.
Biotechnologies have become highly precise genetic tools. Researchers keep discovering their advantages. However, they also continue to fuel debates about their acceptability.
The European Commission’s proposed regulation on certain NGTs would facilitate researchers’ work once it is adopted. However, it has also sparked numerous controversies (see sidebar).
Moreover, biodiversity has multiple definitions related to the societal issues it carries. Even though both ecologists and “pro-GMO” proponents claim to be fierce advocates, they do not have the same conception of biodiversity at all!
Resisting Late Blight
However, the facts remain. Plant biotechnologies promote the growth of ecologically intensive, input-efficient agriculture. In Africa, a local potato variety was rendered resistant to late blight through cisgenesis (inserting gene(s) from a donor plant into a sexually compatible receiving plant) by adding the three resistance genes present in the genetic heritage of wild varieties widespread in the Andes Cordillera. Over the course of selections and crosses, these characteristics had disappeared from the potato genome in favor of other more attractive agronomic criteria (e.g., temperature, yields).
“Reintroducing these resistance genes through conventional breeding would have been very difficult, if not impossible,” claims Georges Freyssinet, president of the French Association of Plant Biotechnologies (AFBV). “It would have required numerous backcrosses, with no guarantee of success, to obtain a new potato variety combining the characteristics of the original variety with resistance to late blight of wild varieties.”
Avoiding Being Outpaced by Climate Change
At the “Plant Biotechnologies and Biodiversity” symposium organized by the AFBV’s scientific council, invited researchers demonstrated that some biotechnologies decode the genomes of ancient plants, sometimes extinct, from their pollen buried in sedimentary layers or thawed permafrost. Climate change is happening so rapidly that plants do not have the means to adapt to the new temperature and precipitation conditions they are subjected to in ecosystems where they have been developing for millennia. However, plant biotechnologies provide effective solutions to address these endemic problems. They contribute to strengthening biodiversity conservation, which previously relied solely on conventional selection techniques. By comparing genomes, it is possible to understand gene evolution over time, as well as their disappearance or appearance.
Cisgenesis and targeted mutagenesis tools make it possible to reintroduce or modify the most interesting genes in the current plant selection game. Until now, researchers could only rely on cell and microplant cultures or cryopreservation to conserve biodiversity.
Obtaining genetically modified plants increases biodiversity because new plant varieties with new characteristics are grown. At the same time, they promote the development of a new microbiota.
Indeed, the cultivation of GM Bt maize varieties, which are resistant to insects, requires fewer plant protection treatments. Additionally, they promote, on their scale, the growth of an ecosystem without having to fear the pathogen destroyed by the GM plant, whereas the multitude of previously performed broad-spectrum treatments destroyed it. This observation is also made in Bt cotton fields or in virus-resistant papaya plantations.
As a result, plant biotechnologies could make biotopes and microbiota more balanced since organisms favorable to plant growth would be rid of harmful pathogens. On the scale of legume root mycorrhizae, it is possible to significantly increase the absorption of atmospheric nitrogen by bacteria by ridding them of other organisms and viruses that impair their function. This would significantly increase crop yields and consequently plant protein production.
New Prospects for Increasing Biodiversity?
“The European Commission’s publication of a proposal covering plants resulting from new genomic techniques (NGTs) in July last year is, according to the French Association of Plant Biotechnologies (AFBV), an important step in helping to develop sustainable agriculture in Europe that can adapt more rapidly to the challenges of climate change.” Until now, they were subject to the 2001/18/EC directive on GMOs. This includes targeted mutagenesis and cisgenesis, for example.
If this new European regulation is accepted, it will differentiate NGT plants based on modifications made to their genome, not the techniques used to obtain them, as is currently the case. NGT-1 plants would be NGT plants that could naturally occur or be conventionally bred. They would be obtained by making fewer than twenty modifications to the genome of the plant they originate from. These modifications must meet one of the five required criteria. For example, it would involve having modified a gene in the target plant to replicate a gene that exists in nature as is.
For these NGT-1 plants, “the rules applicable to GMOs would not apply.” They would be subject to the rules for plants resulting from conventional breeding. In contrast, all other NGT plants, called NGT-2, would remain subject to the rules and requirements of GMO legislation. However, the authorization procedure for these plants would be simplified.
New Commercial Opportunities
The rise of NGT plants is part of the objectives of the European Commission’s Green Deal. With access to them, “farmers will benefit from innovative seeds that require fewer fertilizers, plant protection products, and water to grow,” says AFBV. New markets will open up to them. Until now, for plants sold worldwide, most of the modifications made through targeted mutagenesis have focused on product quality (taste, vitamin content). Consumed foods will be healthier and tastier.
“Europe, which is already missing out on the benefits of GMOs, will also deprive itself of the benefits that targeted mutagenesis should bring,” AFBV wonders. On its website, it is surprised “by the refusal to use NGT-1 plants for agriculture and the organic market when they could benefit from the benefits of these stress-resistant plants, both biotic and abiotic.”
Legislative Path
In the best case, the European Commission’s proposal for NGT plants cannot be applied until after the election of the new European Parliament in June of next year.
The examination of the project is already on the agenda of the Spanish presidency of the European Union. The European Council of Heads of State would adopt it in a few weeks. The agriculture and environment committees of the European Parliament are well on track to approve the text on December 5, before going to plenary session in January 2024. In 2025, a trilogue between representatives of the new Parliament, the European Council, and the European Commission will try to find a compromise to definitively adopt the legislative text.