Cinmethylin controls multiple herbicide resistant Lolium rigidum and its wheat selectivity is P450-based

“Cinmethylin controls multiple herbicide-resistant Lolium rigidum and its wheat selectivity is P450 based” was published in Pest Management Science, by Busi et al.

Cinmethylin is a new (old) herbicide being commercialised by BASF that is pre-emergent selective in wheat. Cinmethylin has been shown to be an inhibitor of acyl ACP thioesterase (Campe et al 2018). Cinmethylin is available in 2020 to growers in Australia and imminent elsewhere.

In this work, led by AHRI researcher Dr Roberto Busi, cinmethylin was pre-emergent pot-tested on a large number of Lolium populations, many of which have complex patterns of resistance to other pre and post-emergence herbicides.

Cinmethylin was found to control Lolium populations that have resistance to other herbicides. Wheat selectivity was evident (provided wheat seed was >than 1 cm below soil surface).   These pot studies indicate that cinmethylin pre-emergent will be effective in controlling Lolium, including populations resistant to other herbicides, in Australian wheat fields and elsewhere. Wheat possibly metabolises cinmethylin by P450s.

Of course, cinmethylin longevity will be determined by use patterns.  High dose mixtures of cinmethylin with other pre-emergent herbicides and rotation between the range of available pre-emergent herbicides will be the most sustainable way to use cinmethylin for longevity.