Effective herbicide resistance management in Avena fatua is a crucial challenge to sustain wheat production. Using classic bioassay confirmed fenoxaprop-P-ethyl resistance in A. fatua biotypes in four districts of Punjab, Pakistan (Khushab, Mianwali, Bhakkar, and Sargodha). The efficacy testing of herbicide mixtures comprising clodinafop-propargyl plus metribuzin, pinoxaden plus sulfosulfuron, pinoxaden plus metribuzin, and sulfosulfuron plus clodinafop-propargyl had concentrations at 100%, 75%, and 50% of the recommended dose for each herbicide to control A. fatua resistant to fenoxaprop-P-ethyl. Results indicated that A. fatua displayed widespread resistance to fenoxaprop-P-ethyl, ranging from 4.12 to 5.49, in all the surveyed districts. Every mixture of herbicides demonstrated 100% mortality at 100% and 75% of the authorized dose, demonstrating high efficacy in suppressing the weeds. At 100% and 75% of the recommended dose, every tested herbicide mixture showed 100% mortality, indicating high efficacy in controlling weeds. At 50% doses, clodinafop-propargyl plus metribuzin exhibited higher efficacy in controlling weeds than other herbicide mixtures. It is the first report of A. fatua from Punjab, Pakistan, stating resistance to fenoxaprop-P-ethyl. The improved herbicide combinations will be beneficial in minimizing the possible emergence of cross-resistance, decreasing wheat production losses, and efficiently managing A. fatua.

Keywords: ACCase resistance, classical bioassay, herbicide resistance, wheat sustainability, wild oat

Key findings: Empirical studies validate the extensive dispersion of fenoxaprop-P-ethyl-resistant A. fatua in major wheat-producing regions, such as Khushab, Mianwali, Bhakkar, and Sargodha, Pakistan. All tested herbicide mixtures effectively suppressed both susceptible and fenoxaprop-P-ethyl-resistant A. fatua biotypes. The combination of metribuzin and clodinafop-propargyl displayed the best efficacy in controlling A. fatua.