Adaptation for herbicide tolerance in populations of Avena fatua

Abstract

A study was conducted to determine whether recurrent treatment of wild oat populations with triallate results in increased tolerance of this herbicide. Among several parameters of seedling growth investigated, percentage emergence, seedling survival, and length of the first leaf were found to be most useful in assessing response to this compound. The results revealed a substantial within-population variability for tolerance. Evidence is presented that recurrent herbicide treatment of wild oat populations by the methods commonly used in the control of this weed species in western Canada results in increased tolerance of triallate.