Genome editing:
Achieving robust varieties faster
With a new legal framework, the European Union is creating the conditions for using genome editing in plant breeding – an important addition to the breeding toolbox.
Only a few millimeters in size and unremarkable at first glance, the cabbage-stem flea beetle can cause substantial yield losses. In just a few years, this pest has become a serious challenge for oilseed rape cultivation in many regions. At the same time, fewer and fewer effective crop protection products are available in the EU.
“Milder temperatures make it much easier for the cabbage-stem flea beetle to overwinter,” says Dr. Anja Matzk, Head of Regulatory Affairs at KWS. “We need new solutions to the growing pest pressure, and we need them as quickly as possible.”
A faster, more targeted approach to breeding
The first step is to search for genes or gene variants that influence a specific trait. In the case of the cabbage-stem flea beetle, scientists at KWS identified relevant “susceptibility genes” – S genes for short. They influence processes in the plant that can make it easier for the pest to infest it. Once the significance of such genes is understood, they can be specifically switched off using genome editing. “Genome editing allows us to introduce specific traits into high-performing varieties much faster and in a more targeted way,” explains Anja Matzk. “Compared to conventional breeding methods, this can accelerate variety development by 20 to 30 percent, depending on the crop.”
We need new solutions to the growing pest pressure, and we need them as quickly as possible.
Anja Matzk | Head of Regulatory Affairs at KWS
Testing under field conditions
In oilseed rape, this approach is showing initial promising results: In greenhouse trials, the cabbage-stem flea beetle caused significantly less feeding damage to the genome-edited plants than to conventional varieties. If this effect is confirmed under field conditions, it could lead to the development of varieties with greater resilience to the pest.
The next step is therefore to test the plants in the field — in England, where oilseed rape is regularly affected by severe cabbage-stem flea beetle infestations. There, the genome-edited plants must demonstrate whether they can also withstand the pest pressure in agricultural practice. Multi-year trials like these, ideally at many different locations, are crucial for developing resilient varieties.
First beetles, then larvae
The cabbage-stem flea beetle affects oilseed rape throughout much of the growing season. Adult beetles move into fields from late summer onwards, feeding on young leaves and laying their eggs. From October, the emerging larvae burrow into leaf stalks and stems, where they can cause significant damage and severely weaken the plants.
Effective control requires a combination of measures throughout the growing season. KWS contributes through breeding innovation: oilseed rape varieties with InsectPROTECT have been shown to exhibit significantly lower levels of larval infestation.
New breeding opportunities
In England, field trials with genome-edited plants have already been possible for the past two years. The EU has now also paved the way for such trials: The new legal framework for New Genomic Techniques went into effect in July 2026. Following a two-year implementation phase, genome-edited plants can be tested in the field from fall 2028 at the earliest. The new requirements recognize that genome editing can introduce changes that could also occur naturally or through conventional breeding methods. For these specific applications, a distinct new regulation now applies. “We have waited a long time for this. The EU decision gives us the clarity we need to move research and development projects forward,” says Anja Matzk.
However, even after successful field trials, there is still a long way to go before a new variety can reach the market. The next steps include official variety approval, during which new variety candidates must demonstrate their performance. This step alone can take up to three years.
KWS background
How does genome editing work?
In conventional breeding, plants are crossbred, and offspring with the desired traits are selected. If a specific trait is to be introduced into high-performing breeding lines, numerous crossing and backcrossing steps are often necessary – a process that takes several years.
Genome editing offers a more direct approach: Once the function of a gene relevant for a specific trait has been identified, it can be altered in a targeted way. A “guide RNA” directs a specific protein to the desired location in the genome, where it cuts the DNA. The plant cell then repairs the cut itself. Depending on the method, DNA build-ing blocks can be precisely removed, replaced, or inserted.
