Chlorsulfuron

T. aestivum's close relative Lolium rigidum was found to be using the same mechanism by Christopher et al 1991 and Cotterman & Saari 1992.

[9] A North American population of Stellaria media was found by Hall and Devine 1990 to be resistant by way of an ALS target mutation rather than by improved disposal.

[10] Another such mechanism - the acetolactate synthase target-site mutation Pro-197–Ser - was found by Roux et al 2004 to be accompanied by a 37% recessive fitness cost in a model (Arabidopsis thaliana).

[14] Crops have also been deliberately made resistant, for example in maize/corn by McCabe et al 1988 using bombardment with the relevant gene attached to tungsten particles.

[16] The estimated use in US agriculture is mapped by the US Geological Service and shows that from 1992 to 2017, the latest date for which figures are available, up to 120,000 pounds (54,000 kg) were applied each year.

US Geological Survey estimate of chlorsulfuron use in the USA to 2017