Synergistic interaction of thymol with Piper ribesioides (Piperales: Piperaceae) extracts and isolated active compounds for enhanced insecticidal activity against Spodoptera exigua (Lepidoptera: Noctuidae)

Chemical and Biological Technologies in Agriculture

Table 4 Impact on detoxification enzymes activity¹ in survived 2nd instar S. exigua after topical application of P. ribesioides extracts post-24 h treatment

Binary mixtures	CE activity	CF2	GST activity	CF2	AChE activity	CF2
Control	1.012^d	–	1.004^de	–	0.939^de
Thymol (LD₁₀) + hexane extract (LD₁₀) 1.21 + 0.65	0.066^a	15.33	0.124^b	8.10	0.323^c	2.91
Thymol (LD₃₀) + hexane extract (LD₁₀) 9.54 + 0.65	0.106^a	9.55	0.074^a	13.57	0.026^a	36.12
Thymol (LD₃₀) + hexane extract (LD₃₀) 9.54 + 3.21	0.451^bc	2.24	0.324^c	3.10	0.227^b	4.14
Thymol (LD₁₀) + CH₂Cl₂ extract (LD₃₀) 1.21 + 1.73	0.923^d	1.10	0.676^cd	1.49	1.036^de	0.91
Thymol (LD₃₀) + CH₂Cl₂ extract (LD₁₀) 9.54 + 0.32	1.114^d	0.91	1.513^e	0.66	0.768^d	1.22
Thymol (LD₃₀) + CH₂Cl₂ extract (LD₃₀) 9.54 + 1.73	0.625^c	1.62	0.651^cd	1.54	2.061^g	0.46
Thymol (LD₁₀) + EtOAc extract (LD₁₀) 1.21 + 0.57	1.044^d	0.97	2.096^f	0.48	1.580^f	0.59
Thymol (LD₃₀) + EtOAc extract (LD₃₀) 9.54 + 1.60	1.947^e	0.52	1.691^ef	0.59	2.140^g	0.44
Thymol (LD₁₀) + MeOH extract (LD₁₀) 1.21 + 2.52	0.439 ^b	2.31	0.697^cd	1.44	0.917^de	1.02
Thymol (LD₁₀) + MeOH extract (LD₃₀) 1.21 + 39.74	0.661^c	1.53	1.082^de	0.93	1.141^e	0.82
Thymol (LD₃₀) + MeOH extract (LD₁₀) 9.54 + 2.52	1.040^d	0.97	0.821^d	1.22	0.443^c	2.12
Thymol (LD₃₀) + MeOH extract (LD₃₀) 9.54 + 39.94	1.117^d	0.91	0.911^d	1.10	1.974^fg	0.48
F-value	140.863		27.678		33.076
P-value	< 0.0001		< 0.0001		< 0.0001

1 Mean values within the same column followed by the same letter of each treatment are not significantly different (P > 0.05) by Tukey's test. The reaction of CE were measured as nM p-nitrophenol/min/mg; GST as nM glutathione conjugated product/min/mg; AChE as µM/min/mg of protein
2 CF is correction factor (detoxification enzyme activity of control / detoxification enzyme activity of treatment)