The Essential Oils Compounds of Lippia multiflora Moldenke and Cymbopogon schoenanthus (L.) Spreng Repel and Affect the Survival of the Maize Pest Spodoptera frugiperda (Lepidoptera: Noctuidae) Larvae
Table 3
Lethal concentrations 50 and 90 (LC50 and LC90), their 95% confidence intervals, and regression parameters for Spodoptera frugiperda larvicidal activity (L2) of essential oils of Lippia multiflora, Cymbopogon. schoenanthus, and their combinations.
Essential oils
Exposure time (h)
LC50 (%)
CI95 (%)
LC90 (%)
CI95 (%)
-value
Chi2
L. multiflora
24
1.91
(0.35–2.23)
2.74
(2.47–3.71)
<0.0001
70.69
C. schoenanthus
1.71
(0.70–2.31)
3.14
(2.55–4.00)
<0.0001
39.40
Lm + Cs (1 : 1)
1.60
(0.34–2.11)
3.10
(2.63–4.12)
<0.0001
38.21
Lm + Cs (1/4 : 3/4)
2.07
(0.42–2.52)
3.70
(3.10–7.05)
<0.001
31.31
Lm + Cs (3/4 : 1/4)
2.04
(0.00–2.57)
3.77
(3.14–7.30)
<0.0001
29.27
L. multiflora
48
1.59
(1.01–1.92)
2.49
(2.14–2.89)
<0.0001
72.76
C. schoenanthus
1.43
(0.73–1.92)
2.66
(2.18–3.30)
<0.0001
50.28
Lm + Cs (1 : 1)
1.20
(0.43–1.58)
2.31
(1.97–2.79)
<0.0001
57.08
Lm + Cs (1/4 : 3/4)
1.57
(0.81–1.92)
2.80
(2.46–3.56)
<0.001
51.59
Lm + Cs (3/4 : 1/4)
1.71
(0.70–2.18)
3.25
(2.77–4.32)
<0.0001
36.87
L. multiflora
72
1.47
(0.93–1.79)
2.27
(1.96–2.66)
<0.0001
78.83
C. schoenanthus
1.37
(0.74–1.79)
2.42
(2.00–2.94)
<0.0001
60.49
Lm + Cs (1 : 1)
1.02
(0.33–1.35)
1.92
(1.63–2.32)
<0.0001
68.82
Lm + Cs (1/4 : 3/4)
1.25
(0.38–1.74)
2.62
(2.16–3.24)
<0.001
44.44
Lm + Cs (3/4 : 1/4)
1.40
(0.56–1.88)
2.85
(2.39–3.56)
<0.0001
41.58
LC: lethal concentration, CI: confident interval, Lm: Lippia multiflora; Cs: Cymbopogon. schoenanthus; Lm + Cs (1 : 1): combination of Lm and Cs at 1 : 1 ratio; Lm + Cs (1/4 : 3/4): combination of Lm and Cs at the ratio 1/4 : 3/4 respectively; Lm + Cs (3/4 : 1/4): combination of Lm and Cs at the ratio 3/4 : 1/4, respectively.