Rapid leaf testing
Rapid leaf testing identifies herbicide resistance at any point in the season
Starting in 2026, ADAS offers leaf herbicide resistance testing for broad-leaved weeds and annual meadow grass. With results available within 21 days, this test enables you to alter herbicide and weed management decisions mid-season if needed.
Leaf tissue herbicide resistance testing can be carried out on Mayweed, Poppy, Fat hen, Groundsel, Chickweed, Sow thistle and annual Meadowgrass.
This leaf tissue herbicide resistance test costs £200.
We can also test oilseed rape and sugar beet to check for the presence of ALS tolerant volunteers. If you are interested, please contact weeds@adas.co.uk.
Order your leaf tissue herbicide resistance testCollecting a broad-leaved weed sample for leaf testing
Sample requirements
- The weed plants need to be healthy and green.
- Take a 3cm long sample from each plant or snip off the leaves from the base of the plant using scissors.
- If the weed is small, you can submit the whole plant if it is 2g or more.
Preparing your sample
- Lay out the samples on a clean, dry surface.
- Blot dry or allow them to dry naturally.
- Keep individual plant samples separate.
Use sheets of paper folded into a concertina shape to keep samples separate, fix the bundles so that leaves don’t fall out. Alternatively, you could sandwich the individual leaves/plants between separate sheets of blue-roll, tissue paper or printer paper.
Ready to send your sample?
When you have collected your sample, post your sample along with the order form to:
Herbicide Resistance Tests, ADAS Boxworth, Cambridge, CB23 4NN
If you require an oilseed rape and sugar beet test to check for the presence of ALS tolerant volunteers, please contact weeds@adas.co.uk.
How we carry out leaf tissue testing
The rapid test is offered only for weed species where the resistance mechanism is a simple target-site mutation.
When these weeds develop resistance to acetolactate synthase (ALS) herbicides (or PS-II herbicides in the case of fat hen), a change occurs in the DNA sequence of the gene that controls the herbicide target site. This genetic change prevents the herbicide from working correctly.
On all the samples we receive, the DNA from each leaf/plant is extracted, and we assess changes at the herbicide target site.
If results confirm resistance, growers are advised to adjust their current weed management as soon as possible. If no mutation is found, growers can continue with the current herbicide programme. If poor control remains a problem, it is likely because of other factors, such as timing or application quality.