What is the leaf-test?
In our leaf-test, the genetic material of a plant is analyzed. Target-site resistance can be diagnosed using the leaf-test. The – so called – single nucleotide polymorphisms (SNPs) in the target gene are analyzed and used in the diagnosis.
When is the the leaf-test used?
The test is used if, after applying the herbicides and completing reaction in the field, resistance is indicated. Reduced efficacy of herbicides can have many causes. An application error perhaps? If you suspect herbicide resistance in your field, you should take a moment and to perform a diagnosis by exclusion (see under: http://www.hracglobal.com/pages/detectingherbicideresistance.aspx the chapter „Field Observation“).
In order to proof target-site resistance, PlantaLyt provides tests for various plant species and herbicides in different cropping systems. A leaf – test is also suitable for epidemiological studies, e.g. to find out the variations of resistances distributed in a region.
- Testing target-site resistance of grasses to ACCase inhibitors (HRAC A) in cereals, oilseed rape, sugar beet, and further crops
- Testing target-site resistance of weeds and grass to ALS inhibitors (HRAC B) in cereals and maize
- Examining target-site resistance of weeds and weed grasses to PS II inhibitors (HRAC C) in cereals, maize and sugar beet
How long does the leaf Test take?
Upon receipt of the samples, we immediately begin analysis in the laboratory. The Analysis takes ten working days.
What Information does the leaf-test provide and how do you benefit from this?
Using the leaf-test, you can determine whether target-site resistance has occured and how far the resistance has progressed in the field using relatively simple sampling (leaf samples from eight plants of the species to be tested are required). A diagnosis by means of the leaf-test will help you and your advisor to rethink your weed management. A conclusion can be drawn regarding the application of herbicides with the same mechanism of action in subsequent cultures. Target-site resistance can exist alone or can be a part of a complex of different resistance mechanisms within a population.
If there is no target-site resistance, this raises the question as to whether other mechanisms of resistance are present or if in fact a simple application error has occured. This requires obtaining further information on resistance or cross-resistance to other products and the underlying mechanisms. Here we can assist by preparing a Resistance Profile, for example.
What sample material is required for the leaf-test?
About 5 to 10 cm long pieces of leaves are required. Each leaf must come from an individual plant. Therefore, we need one peace of leaf from each of eight individual plants! It is best to collect these from within the hotspot for the suspected resistance.
We provide tests for various weeds and crop situations. Please contact us for further information (info@plantalyt.com).
Please find general instructions for sampling and shipping in the following Video:
