Table 1. AHAS mutations in field Kochia scoparia populations along with their experimentally determined resistance to tribenuron methyl and thifensulfuron methyl.

Mutation type	Residue substitution		Activity	Reference
Wild type	None		Sa	33,34
Single mutation	Pro197	Ala	Rb	33
		Arg	R	33–35
		Gln	R	33–35
		Glu	R	30
		Leu	R	33
		Lys	R	33,34
		Met	R	33
		Ser	R	33,35
		Thr	R	33,34
		Trp	R	33
	Val225	Ile	R	33
	Gly268	Asp	S	33,34
	Glu284	Val	S	33,34
	Asp376	Glu	R	33–35
	Asn434	Lys	S	33
	Trp574	Leu	R	33–35
		Arg	R	33
Double mutation	Pro197Ala+Trp574Leu		R	34
	Pro197Gln+Asp376Glu		R	33
	Pro197Ser+Asp376Glu		R	33
	Pro197Thr+Asp376Glu		R	33
	Pro197Arg+Trp574Leu		R	33
	Pro197Gln+Trp574Arg		R	33
	Pro197Gln+Trp574Leu		R	33–35
	Pro197Leu+Trp574Leu		R	33
	Pro197Ser+Trp574Leu		R	33,34
	Pro197Thr+Trp574Leu		R	33,34
	Asp376Glu+Trp574Leu		R	33,35

^aR = resistant

^bS = susceptible