Enhanced Metabolism Evolved High-Level Resistance to Fenoxaprop-P-Ethyl in Alopecurus japonicus

Alopecurus japonicus has been a serious weed across China and developed resistance to the acetyl-CoA carboxylase (ACCase)-inhibiting herbicide. The A. ACCase gene mutations accounting for target-site (TSR) have clarified, while non-target-site (NTSR) is not distinct. Here, dose–response testing indicated that an population (R) was resistant four ACCase-inhibiting herbicides fenoxaprop-P-ethyl, sethoxydim, clethodim, pinoxaden. Compared with herbicide-susceptible (S), no known TSR in were identified R using sequencing. To investigate NTSR mechanism, increased metabolism of fenoxaprop-P-ethyl detected high-performance liquid chromatography (HPLC) analysis. Notably, cannot be reversed by P450 GST inhibitors. RNA-seq performed further explore mechanisms, eight candidate contigs (four glycosyl transferases (GT) ATP-binding cassette (ABC) transporters) chosen their expression patterns validated RT-qPCR. Three GT three ABC transporter constitutively upregulated population. In short, six expressed highly causing enhanced appear involved resistance.