The present invention is directed to plants having increased tolerance to
an imidazolinone herbicide. More particularly, the present invention
includes rice plants containing at least one variant AHAS nucleic acid
such as an imidazolinone tolerant IMINTA 1, 4 or 5 lines comprising an
alanine to threonine substitution as compared to the wild-type AHAS. The
present invention also includes seeds produced by these rice plants and
methods of controlling weeds in the vicinity of these rice plants.