A holistic approach in herbicide resistance research and management: from resistance detection to sustainable weed control

Agricultural weeds rapidly adapt to human-imposed selection, notably evolving herbicide resistance. We adopted a holistic approach—combining rapid resistance confirmation, mechanistic investigation, alternative control testing, and population modeling—to manage glyphosate-resistant Amaranthus palmeri in Argentine soybean systems. Glyphosate resistance in the studied Villa Valeria population was mainly due to a P106S target-site mutation in the EPSPS gene, with minor contributions from EPSPS gene duplication/overexpression. Alternative herbicides such as fomesafen effectively controlled resistant plants. Modeling suggested solo herbicide use primarily selects a single resistance mechanism and highlighted the importance of residual herbicides and chemical diversity for sustainability. We discuss the value of interdisciplinary research in understanding and managing evolving weeds.