The potential of eugenol as a nematicidal agent against Meloidogyne javanica (Treub) Chitwood Publié en ligne: 06 nov. 2020 Pages: 1 - 10 © 2020 Eleni Nasiou et al., published by Sciendo This work is licensed under the Creative Commons Attribution 4.0 International License.
Figure 1: Molecular structure of eugenol. Figure 2: Pot trial methodology on the contact and vapor effect of eugenol against M. javanica. Figure 3: Effect of eugenol on M. javanica hatch, after immersion of egg masses at the dose rates of 1,000, 500, 250, 125, 62.5, and 0 ppm for 35 days. Values are means of combined results from two experiments with five replicates each, since no significant differences were observed after ANOVA using the data of both experiments. Samples in boxplots contain a large amount of variation among the treatment means relative to the amount of variation within the treatment. F statistic is defined as: (variation among the treatment means)/(variation among individuals in the same treatment). F value is large indicating that the means are significantly different and is evidence against the null hypothesis that assumes equal means. F is zero only when all group means are the same. Figure 4: Effect of eugenol on contact and vapor mortality of M. javanica J2 in the soil, at the dose rates of 1,000, 500, 250, 125, and 62.5 ppm at 20 to 22°C and 30°C. Values are means of combined data from two experiments with four replicates each, since no significant differences were observed after ANOVA using the data of both experiments Error bars represent the standard deviation of mean. Bars with the same letter indicate no significant differences according to LSD test; upper case letters refer to the contact bioassay, lower case letters to the vapor bioassay. Figure 5: Numbers of females of M. javanica per gram of root after immersion in eugenol solutions at the dose rates of 0, 33.75, 67.5, 135, and 270 ppm for 24, 48, and 96 hr. Error bars represent the standard deviation of mean (n = 5). Bars having the same pattern with the same letter indicate no significant differences according to LSD test (P < 0.001). Effect of eugenol on the motility of Meloidogyne javanica J2 after immersion in test solutions at the doses of 1,000, 500, 250, 125, 62.5, and 0 ppm for 12, 24, 48, and 96 hr.
Exposure time (hr)
12
24
48
96
Dose (ppm)
Dead J2 (%)
Dead J2 (%)
Dead J2 (%)
Dead J2 (%)
0
0 d
0.8 d
1.3 d
4.7 e
62.5
0.4 d
1.6 d
2.4 d
10.7 d
125
0.7 d
2 d
6.4 c
19.8 c
250
6.5 c
6.9 c
24.5 b
80.8 b
500
74.1 b
92.2 b
99.8 a
100 a
1000
99.5 a
100 a
100 a
100 a
Effect of eugenol on the differentiation of Meloidogyne javanica eggs, after immersion of undifferentiated eggs at different doses of 1,000, 500, 250, 125, 62.5, and 0 ppm.
Exposure time (21 days)
Dose (ppm)
Eggs differentiation (%)
0
92.1 a
62.5
90.6 a
125
90.5 a
250
82.1 a
500
66.2 b
1000
21.4 c