PPO Inhibitor (HG 14) Herbicide Injury in Corn
Published: 09/08/2023
Protoporphyrinogen oxidase (PPO) inhibitors, or Group 14 herbicides, limit the ability of the plant to create chlorophyll needed for the photosynthesis.
Direct application of PPO herbicides to corn is the most common cause of injury; however, some herbicides may occasionally cause carryover injury. As well as causing rapid tissue death, PPO inhibitor injury symptoms resulting from foliar applications may also cause leaf burning and damage to leaves within the whorl, preventing the unfurling of new leaves. Symptoms from carryover of PPO-inhibiting herbicides include veinal chlorosis and a weakened or collapsed tissue at the midrib. Fomesafen carryover is a common issue regarding PPO injury in corn.
PPO inhibitor herbicide injury to corn.
Kristine Schaefer.
Fomesafen inury to corn.
Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
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.
Fomesafen injury to corn. Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Flumioxazin injury to corn. Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
Carfentrazone injury to corn. Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
PPO inhibitor herbicide injury to corn. By Kristine Schaefer.
PPO inhibitor herbicide injury to corn. By Kristine Schaefer.
Gallery images courtesy Kristine Schaefer, Iowa State University and Cal Shumway, Bob Scott, and John Boyd, www.uada.edu.
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