Herbicide cross resistance in weeds.pdf

at SciVerse ScienceDirect Crop Protection 35 (2012) 15e28Contents lists availableCrop Protection journal homepage: www.elsevier .com/locate/croproHerbicide cross resistance in weeds Hugh J. Beckie a,*, Fran?ois J. Tardif b a Saskatoon Research Centre, Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, Saskatchewan S7N 0X2, Canada bDepartment of Plant Agriculture, University of Guelph, Guelph, Ontario N1G 2W1, Canadaa r t i c l e i n f o Article history: Received 25 July 2011 Received in revised form 20 December 2011 Accepted 26 December 2011 Keywords: ACCase inhibitor ALS inhibitor Herbicide resistance Integrated weed management Resistance management Selection pressure* Corresponding author. Tel.: t1 306 9567251; fax: E-mail addresses: hugh.beckie@agr.gc.ca (H.J. (F.J. Tardif). 0261-2194/$ e see front matter Crown Copyright
2 doi:10.1016/j.cropro.2011.12.018a b s t r a c t With no major new site-of-action herbicide introduced into the marketplace in the last 20 years, the stagnation or decline in available herbicides in the past decade in a number of jurisdictions, and ever- increasing incidence of herbicide-resistant (HR) weeds, more efficient use of our existing herbicide tools will be required to proactively or reactively manage HR weed populations. Herbicide-resistant weed management can be aided by crop cultivars with alternative single or stacked herbicide-resistance traits, such as synthetic auxins, which will become increasingly available to growers in the future. An exami- nation of cross-resistance patterns in HR weed populations may inform proactive or reactive HR weed management through better insights into the potential for HR trait-stacked crops to manage HR weed biotypes as well as identify possible effective alternative herbicide options for growers. Clethodim is the lowest resistance risk acetyl-CoA carboxylase (ACC) inhibiting herbicide, with only two of eleven target- site mutations (amino acid substitutions) in weed populations tha