Pro-197-Ser Mutation and Cytochrome P450-Mediated Metabolism Conferring Resistance to Flucarbazone-Sodium in .

In crop fields, resistance to acetolactate synthase (ALS)-inhibiting herbicides found in many troublesome weed species, including Thunb, is a worldwide problem. In particular, the development of herbicide resistance in is a severe threat to wheat production in China. The purpose of this research was to investigate the physiological and molecular basis of resistance to flucarbazone-sodium. Dose-response analysis demonstrated that, compared with the susceptible (S) population, the resistant (R) population exhibited a 120-fold increase in flucarbazone-sodium resistance. Nucleotide sequence alignment of the ALS gene indicated that the Pro-197-Ser mutation in ALS was associated with resistance to flucarbazone-sodium in the R population. The results of a malathion pretreatment study showed that might also have remarkable cytochrome P450 monooxygenase (P450)-mediated metabolic resistance. This is the first report of a Pro-197-Ser mutation and P450-mediated metabolism conferring resistance to flucarbazone-sodium in .