File:T--Goettingen--competitionassay overview als jpg mithintergrund.png.jpg

The basic principle of the competition assay for glyphosate detection. In the absence of glyphosate (no selective pressure), both strains grow with the same rate. When glyphosate is present, the herbicide-resistant strain (expressing an orange fluorophore gene) will outcompete the wild type strain. Thus, the velocity at which the wild type strain is eliminated from the co-culture is indicative for the glyphosate present in the culture or test sample.