Evolution of herbicide resistance in mugwort (Ambrosia artemisiifolia L.): search for genetic determinisms and application to molecular diagnosis

Common ragweed (Ambrosia artemisiifolia L.), a particularly troublesome and allergenic weed, is mainly controlled in agricultural fields using ALS inhibitor herbicides. Recent cases of herbicide resistance have been reported in France and are jeopardising the efficacy of this mode of action. Both target site resistance (TSR, structural mutation in ALS gene) and non target site resistance (NTSR, regulatory and/or structural mutations in secondary metabolism) are involved. The fundamental aim of this work was to identify the genetic determinisms of resistance to ALS inhibitors that have evolved in common ragweed populations in France. As an applied objective, this work also aimed to prepare t…