Table 4.

Parameter estimates for logistic analysis of glufosinate dose required to cause 50% inhibition of GS activity in susceptible (S) and resistant (R) E. indica and in purified yeast recombinant wild-type (WT) and mutant (R59) EiGS1-1 protein.

Sample		C	D	b	I50 (mM)	P-value (I50)	I50 ratio (R59/WT, R/S)
Yeast recombinant protein	EiGS1-1-WT	0.28 ± 0.27	98 ± 0.18	−1.43 ± 0.02	0.15 ± 0.001	P<0.0001	/
	EiGS1-1-R59	−1.5 ± 0.29	98 ± 0.16	−1.39 ± 0.02	0.35 ± 0.003	P<0.0001	2.3
Leaf extract of E. indica	EiGS-S	0.007 ± 1.97	99 ± 2.25	−1.21 ± 0.12	0.059 ± 0.005	P<0.001	/
	EiGS-R	0.17 ± 2.7	100 ± 2.34	−1.05 0.11	0.09 ± 0.009	P<0.001	1.5

The I₅₀ values estimated for WT and R59 lines, and S and R populations are significantly different according to the t-test, P<0.0001.