BASF Canada has developed a lentil line tolerant to imidazolinone herbicides. This L. culinaris line, designated line RH44, exhibited no significant injury when treated with imidazolinone herbicides at normal field application rates. This will allow the use of imidazolinones in postemergence on lentil crops, thus providing an alternative means of weed control in lentil production.<br>The development of line RH44 was accomplished using chemically induced seed mutagenesis. The herbicide tolerance trait is conferred by a single point mutation modification of the acetohydroxyacid synthase (AHAS) gene such that this enzyme, the target of imidazolinone herbicides, is no longer affected by imidazolinones.