Table 1.

Resistance ratios towards beta-cypermethrin, matrine, and azadirachtin of field populations of O. asiaticus from Inner Mongolia compared to a susceptible strain (SS)

Insecticides	Population	χ2a	Slope ± SE	LC50 (µg L−1)	95% CL	RRb (R/S)
Beta-cypermethrin	SS	2.36*	2.30 ± 0.51	0.21	0.17–0.30	1.00
	AB	1.67*	1.83 ± 0.39	0.77	0.46–1.13	3.68
	DB	4.55*	2.67 ± 0.41	1.41	0.82–1.94	6.72
	SB	2.14*	3.13 ± 0.58	1.65	0.73–2.15	7.85
	XC	0.97*	1.16 ± 0.36	0.78	0.46–1.14	3.74
	XB	2.18*	2.34 ± 0.42	0.99	0.49–1.36	4.76
	ZB	1.45*	1.68 ± 0.33	1.13	0.67–1.45	5.64
Matrine	SS	0.83*	1.63 ± 0.38	0.43	0.42–0.65	1.00
	AB	1.97*	1.97 ± 0.41	1.71	1.32–3.75	3.98
	DB	2.34*	1.82 ± 0.36	2.05	1.75–4.25	4.76
	SB	1.20*	2.63 ± 0.47	2.55	2.30–4.16	5.92
	XC	3.19*	2.06 ± 0.41	2.74	2.43–4.70	6.38
	XB	4.15*	1.89 ± 0.39	0.92	0.83–2.27	2.13
	ZB	1.74*	2.24 ± 0.41	1.49	1.31–3.75	3.46
Azadirachtin	SS	2.13*	3.34 ± 0.64	0.54	0.31–0.59	1.00
	AB	3.62*	3.22 ± 0.61	1.25	0.62–1.74	2.32
	DB	2.27*	3.01 ± 0.54	1.31	0.67–1.59	2.41
	SB	5.01*	2.15 ± 0.46	1.39	0.73–1.66	2.57
	XC	0.92*	1.79 ± 0.29	1.05	0.29–1.82	1.95
	XB	1.67*	1.68 ± 0.28	0.95	0.35–1.57	1.76
	ZB	2.54*	2.10 ± 0.31	0.85	0.32–1.62	1.56

^*Meant pass the χ² test.

^bPearson chi-square, goodness-of-fit test.

^cRR: resistance ratio = LC₅₀ of the field strain/LC₅₀ of the susceptible strain.