Submitted to: Agrichemical and Environmental News
Publication Type: Trade Journal
Publication Acceptance Date: January 1, 2001
Publication Date: February 1, 2001
Citation: BOYDSTON, R.A. HERBICIDE MODE OF ACTION PRIMER. AGRICHEMICAL AND ENVIRONMENTAL NEWS, WSU COOP EXT NO 178. FEB 2001. Technical Abstract: Common herbicides used in Washington State were discussed according to mode of action. Knowledge of a herbicide's mode of action can be useful in selecting and applying the proper herbicide for a given weed control problem and in helping to understand herbicide resistance and designing strategies to delay or prevent the development of herbicide resistant weeds. Herbicides with similar modes of action should be rotated or tank mixed with herbicides having different modes of action to prevent continuous selection of naturally occurring herbicide resistant weeds. Knowing an herbicide's mode of action can also prove useful in resolving problems with herbicide carryover or drift. Herbicides that inhibit different functions or enzymes in the plant often cause distinct injury symptoms. The following groups of herbicides were discussed: Acetyl CoA carboxylase (ACCase) inhibitors (lipid synthesis inhibitors), acetolactate synthase (ALS) inhibitors, microtubule assembly inhibitors, synthetic auxins (phenoxys, benzoics, picolinic acids), photosystem II inhibitors (triazines and uracils, benzothiadiazoles and nitriles, ureas), photosystem I inhibitors, lipid synthesis inhibitors (not ACCase), EPSP synthase inhibitors, glutamine synthetase inhibitors, chloroacetamides, benzofuran, protoporphyrinogen oxidase (Protox) inhibitors, and carotenoid synthesis inhibitors.