CYP94D ‐2 enhances haloxyfop‐R‐methyl metabolism and confers herbicide resistance in Polypogon fugax

BACKGROUND: Polypogon fugax is a problematic annual grass weed that severely threatens oilseed rape and wheat production by competing for essential resources and reducing crop yields. Haloxyfop-R-methyl has been widely used for its effective control; however, its intensive and prolonged application has driven the rapid evolution of resistance in P. fugax populations. RESULTS: In this study, a CYP94 family gene, designated CYP94D-2, was identified from a previously characterized haloxyfop-R-methyl-resistant P. fugax population and showed markedly elevated expression. Functional analysis revealed that rice plants overexpressing CYP94D-2 showed significantly reduced growth inhibition after haloxyfop-R-methyl treatment, accompanied by enhanced herbicide-metabolizing capacity. Molecular docking analysis further supported a strong interaction between CYP94D-2 and haloxyfop-R-methyl, consistent with its potential to catalyze efficient herbicide metabolism. CONCLUSION: These results demonstrate that CYP94D-2 is involved in haloxyfop-R-methyl resistance via a metabolism-based mechanism. This study expands our understanding of the CYP94 family's role in herbicide resistance and provides new insights into the molecular basis of non-target-site resistance in weeds.