Screening Waterhemp for Herbicide Resistance
Herbicide-resistant waterhemp populations continue to expand into more areas of Illinois each season. Waterhemp has evolved resistance to herbicides encompassing more mechanisms of action than any other Illinois weed species, including resistance to inhibitors of acetolactate synthase (ALS), photosystem II (PSII), protoporphyrinogen oxidase (PPO), enolpyruvyl shikimate-3-phosphate synthase (EPSPS) and hydroxyphenyl pyruvate dioxygenase (HPPD). Not every individual waterhemp plant is resistant to one or more herbicides, but the majority of field-level waterhemp populations contain one or more types of herbicide resistance. …