ACCase (HG 1) Herbicide Injury in Corn
Published: 09/07/2023
DOI: doi://18374jdf83f3
Acetyl-coa carboxylase (ACCase) inhibitors, Group 1 herbicides, inhibit the ACCase enzyme that aids in the production of fatty acids and lipid production.
Corn is very susceptible to ACCase inhibitor herbicides. Enlist corn hybrids are resistant to aryloxyphenoxypropionate or FOP herbicides such as quizalofop, but are still very susceptible to the cyclohexanediones or DIM herbicides such as clethodim. Injury often occurs from contaminated sprayers, physical drift from adjacent fields, or applications to fields during planting or prior to planting when the minimum replant interval is not followed. Symptoms include bands of chlorotic (yellowing) or bleaching of tissue on leaves at lower concentrations. At lethal concentrations, the growing point is killed and rots in the whorl. In the instance a Group 1 herbicide is applied prior to or at planting, a loss in stand can occur.
Sethoxydim injury to corn.
Cal Shumway, Bob Scott, and John Boyd, www.uada.edu
Cyhalofop injury to corn.
Cal Shumway, Bob Scott, and John Boyd, www.uada.edu
Symptoms of ACCase herbicide injury may resemble injury from other herbicides, such as ALS-inhibitor herbicide injury. Initial symptoms, or responses to a moderate dose, can appear similar to drought stress. ACCase injury is indicated when the top growth can be easily pulled from the plant and the base is rotten.
See the Herbicide Classification Chart from Take Action for herbicide selection information to help slow the development of resistant weeds.
Prepared and reviewed by Dr. Thomas (Tommy) Butts, University of Arkansas; Dr. Joe Ikley, North Dakota State University; the Integrated Pest Management Program at Iowa State University; Dr. Sarah Lancaster, Kansas State University; Dr. Travis Legleiter, University of Kentucky; and Dr. Rodrigo Werle, University of Wisconsin-Madison.
Cyhalofop injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Cyhalofop injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Cyhalofop injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Sethoxydim injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Fluazifop injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Sethoxydim injury to corn. By Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Gallery images courtesy Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
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