Alleles Contributing to ACCase-Resistance in an Italian Ryegrass (Lolium perenne ssp. multiflorum) Population from Oregon. Issue 3 (September 2014)

• Record Type: Journal Article
• Authors: Martins, Bianca A. B.; Sánchez-Olguín, Elena; Perez-Jones, Alejandro; Hulting, Andrew G.; Mallory-Smith, Carol
• Is Part Of: Weed science. Volume 62: Issue 3(2014)
• Page Start: 468
• Page End: 473
• Publication Date: 2014-09
• Subjects: Clethodim, -- clodinafop, -- pinoxaden, -- sethoxydim, -- Italian ryegrass, Lolium perenne L. ssp. multiflorum (Lam.) Husnot LOLMU, -- winter wheat, Triticum aestivum L.; Acetyl-CoA carboxylase, -- aryloxyphenoxypropionate, -- cross-resistance, -- cyclohexanedione, -- phenylpyrazolin, -- target-site resistance; 632.505
• DOI: 10.1614/WS-D-13-00169.1
• Languages: English
• ISSNs: 0043-1745

Abstract

Abstract : Acetyl-coenzyme A carboxylase (ACCase)–resistant Italian ryegrass is one of the most difficult-to-control weeds in United States wheat-production systems. Seed was collected from a suspected ACCase-resistant Italian ryegrass population in a winter wheat field with a history of ACCase-inhibitor herbicide use. This study investigated cross-resistance patterns in this Italian ryegrass population. Resistance was identified to the commercial dose of the ACCase herbicides pinoxaden, clethodim, sethoxydim, and clodinafop. Partial chloroplastic ACCase sequences revealed aspartate-to-glycine or isoleucine-to-asparagine substitutions at positions 2078 or 2041 in individuals of the resistant population. This is the first report, to our knowledge, of Asp-2078-Gly and Ile-2041-Asn substitutions in ACCase-resistant Italian ryegrass in the United States. Associating the occurrence of resistance alleles with resistance to specific active ingredients provides a better understanding of ACCase cross-resistance in Italian ryegrass and possibly options for its control.