Nucleotide sequences are disclosed that may be used to impart herbicide resistance to green plants. The sources of novel herbicide resistance were originally isolated in mutant rice plants. The sequences impart pre-emergence resistance, post-emergence resistance, or both pre-emergence resistance and post-emergence resistance to multiple herbicides. To date, resistance has been demonstrated against at least the following herbicides: imazethapyr, imazapic, imazapyr, imazamox, sulfometuron methyl, imazaquin, chlorimuron ethyl, metsulfuron methyl, rimsulfuron, thifensulfuron methyl, pyrithiobac sodium, tribenuron methyl, and nicosulfuron. Green plants transformed with these sequences are resistant to these herbicides and to derivatives of these herbicides, and to at least some of the other herbicides that normally inhibit acetohydroxyacid synthase (AHAS), particularly imidazolinone and sulfonylurea herbicides.