Individual and combined impact of nuclear polyhedrosis virus and spinosad to control the tropical armyworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), in cotton in Pakistan

Egyptian Journal of Biological Pest Control

Table 2 LT₅₀ values of Spodoptera litura larvae exposed to various concentrations of V-SpltNPV

Larval instars	Concentrations OBs/ml	LT₅₀ (days)	Fiducial limit (95%) lower-upper	Slope ± S.E.	χ2	Df	P
2^nd	1 × 10⁸ OBs/ml	4.99	4.23–5.64	1.27 ± 0.11	6.76	6	0.34
	1 × 10⁷ OBs/ml	6.43	5.45–7.25	1.04 ± 0.11	9.75	6	0.13
	1 × 10⁶ OBs/ml	7.40	6.32–8.31	0.96 ± 0.11	3.02	6	0.80
	1 × 10⁵ OBs/ml	8.73	7.71–9.64	1.04 ± 0.11	1.58	6	0.95
	1 × 10⁴ OBs/ml	11.13	10.15–12.15	1.19 ± 0.11	2.03	6	0.91
3^rd	1 × 10⁸ OBs/ml	6.61	5.76–7.33	1.21 ± 0.14	1.65	4	0.79
	1 × 10⁷ OBs/ml	8.17	7.31–8.97	1.23 ± 0.15	1.53	4	0.82
	1 × 10⁶ OBs/ml	9.57	8.70–10.52	1.32 ± 0.16	2.93	4	0.56
	1 × 10⁵ OBs/ml	11.73	10.63–13.34	1.38 ± 0.19	0.97	4	0.91
	1 × 10⁴ OBs/ml	12.35	11.30–13.87	1.65 ± 0.21	0.37	4	0.98
4^th	1 × 10⁸ OBs/ml	7.49	6.88–8.13	1.88 ± 0.25	3.57	2	0.16
	1 × 10⁷ OBs/ml	8.18	7.54–8.98	1.94 ± 0.27	4.58	2	0.10
	1 × 10⁶ OBs/ml	9.13	8.35–10.32	1.95 ± 0.30	5.53	2	0.06
	1 × 10⁵ OBs/ml	10.19	9.25–11.82	2.24 ± 0.35	5.42	2	0.06
	1 × 10⁴ OBs/ml	11.11	9.96–13.37	2.44 ± 0.41	7.55	2	0.02