title: Chemical marker for ALS-inhibitor herbicides: 2-aminobutyric acid proportional in sub-lethal applications.
abstract: A chemical profiling technique for sub-lethal acetolactate synthase (ALS)-inhibitor herbicides (e.g., sulfonylureas, imidazolines, triazolopyrimidine sulfonanilides, and pyrimidyloxy salicylic) was developed using 2-aminobutyric acid, and was found to be directly proportional to application rates in field studies on two varieties of potato plants. An uncomplicated, benign-by-design analytical method for the determination of 2-aminobutyric acid in plant tissue was developed. The method is simple, fast, and automated, entailing a water-trichloroacetic acid extraction followed by precolumn on-line derivatization using o-phthalaldehyde (OPA) solution and liquid chromatographic analyses. Use of reagents and chlorinated organic solvents, and generation of waste, are minimized as compared to other ALS-inhibitor herbicide analytical techniques. Recoveries for a series of fortified plant tissues ranged from 82 to 103%. Two 20-day field trials on two potato varieties, Russet Burbank and Shepody, were conducted during the 2000 and 2001 growing seasons. The study demonstrated that the 2-aminobutyric acid method is an excellent, selective chemical marker technique for ALS-inhibitor herbicides for real world plant matrixes.
authors.affiliation: Food Safety and Environmental Stewardship Program, Environmental and Molecular Toxicology Department, 1007 Agricultural Life Sciences Building, Oregon State University, Corvallis, OR 97331-7301, USA.
authors.forename: Bob R
authors.initials: BR
authors.lastname: Loper
authors.forename: William T
authors.initials: WT
authors.lastname: Cobb
authors.forename: Kim A
authors.initials: KA
authors.lastname: Anderson
mesh_terms: D000095:Acetolactate Synthase / Q000037:antagonists & inhibitors*; D000613:Aminobutyrates / Q000032:analysis*; D001322:Autoanalysis; D002853:Chromatography, Liquid / Q000379:methods; D004791:Enzyme Inhibitors / Q000008:administration & dosage*; D006540:Herbicides / Q000008:administration & dosage*; D007700:Kinetics; D011198:Solanum tuberosum / Q000737:chemistry*; D014238:Trichloroacetic Acid; D009764:o-Phthalaldehyde
chemical_list: D000613:Aminobutyrates; D004791:Enzyme Inhibitors; D006540:Herbicides; D014238:Trichloroacetic Acid; D009764:o-Phthalaldehyde; C012223:alpha-aminobutyric acid; D000095:Acetolactate Synthase