What can we learn from practical examples of greenhouse testing?
Current knowledge shows: New resistance mechanisms are not expected.
Each weed species – whether black-grass, ryegrass, or silky-bent grass – has its own repertoire of resistance mechanisms.
These are not evenly distributed but vary from field to field.
Therefore, knowing the individual resistance profile of your field is the critical foundation for sustainable and economically successful management.
Why a resistance profile is crucial
If you know the resistance profile of your field – for example, against black-grass – you also know which herbicides are still effective and what flexibility you have in your weed control strategy.
Together with your crop production advisor, you can then analyze and adapt your farming system to preserve these options in the long term.
Even if your greenhouse test shows no current resistance, prevention is both sensible and necessary.
Because known resistance mechanisms could theoretically develop on any field if selection pressure is present.
Goal: Reduce herbicide pressure – avoid selection
The strategy is clear:
Relieve herbicides, strengthen agronomic measures, and actively prevent the selection of resistant biotypes:
Steps to take:
- Create a resistance profile
→ Which problem species (e.g., black-grass) are present? What resistances have been detected? - Define your options
→ Which herbicides are still reliably effective? - Rethink crop rotation
→ Are there meaningful adjustments to reduce pressure? - Adapt sowing dates and farming systems
→ Options include delayed sowing, cover crops, soil cultivation, etc. - Interim testing if deviations occur
→ If field observations differ from expectations, conduct an interim test.
Conclusion: Know, analyze, act
Those who maintain full flexibility („full toolbox“) can react quickly and secure weed control over the long term.
However, this requires openness, expertise, and active dialogue.
Yes – it takes work. But it pays off.
Locally adapted agronomic modifications need experienced advice.
We support you in creating the resistance profile and interpreting the greenhouse test results.
Your crop production advisor supports you in choosing suitable strategies – with and without herbicides.
Together with your advisor, we help safeguard your herbicide effectiveness – and thus the economic viability of your farm.
