Researchers have found that some UK populations of sterile brome (Bromus sterilis) have reduced sensitivity to glyphosate and are in the process of evolving resistance.
Results from the research, led by Laura Davies, based at ADAS Boxworth in Cambridgeshire, and published in Weed Science, indicate that control of sensitive populations of sterile brome using glyphosate ranged from 49 per cent to 82 per cent and suspected resistant populations, from 21 per cent to 30 per cent.
Suspected resistant populations were incompletely controlled at the recommended field rate of glyphosate (540g/ha), while adjacent unexposed populations were completely controlled, according to the research report.
The authors say: “We conclude that some UK populations of B. sterilis have reduced glyphosate sensitivity and are in the process of evolving resistance. This is the first reported case of reduced glyphosate sensitivity in any UK weed species and in B. sterilis worldwide. This, coupled with increasing glyphosate use, highlights the need for increased vigilance and monitoring for glyphosate resistance in the United Kingdom.”