Table 2.
Percentage inactive or dead Meloidogyne incognita second-stage juveniles (J2) in Vetiveria zizanioides (vetiver) root ethanol (VRE) extracts, Tagetes patula (French marigold cv. Durango Mix) root ethanol (FMRE) extract, and in vetiver oil (VO). Extracts were prepared from greenhouse-grown, 2-mon-old and 4-yr-old vetiver cv. Sierra, and from field-grown, 1-yr-old cv. Songkha 3.
| Percentage inactive J2 | Percentage dead J2 | ||
|---|---|---|---|
| Treatmenta | Day 1 | Day 2 | Day 3 rinsed |
| FMRE 0.95 mg/ml | 34.9 aBb | 30.7 aB | 69.1 aA |
| 2-mon VRE 0.95 mg/ml | 24.9 abcB | 28.0 abB | 38.3 bcA |
| 1-yr VRE 0.95 mg/ml | 27.6 abB | 26.5 abB | 42.4 bA |
| 4-yr VRE 0.95 mg/ml | 29.7 abB | 30.0 aB | 41.9 bA |
| VO 0.95 mg/ml | 20.3 bcdA | 12.6 cdA | 17.1 deA |
| 0.95% CTD | 12.9 dA | 8.0 dA | 11.3 eA |
| FMRE 0.095 mg/ml | 13.7 cdB | 17.0 bcdB | 35.0 bcA |
| 2-mon VRE 0.095 mg/ml | 16.2 cdA | 20.2 abcA | 24.0 cdeA |
| 1-yr VRE 0.095 mg/ml | 16.2 cdB | 13.9 cdB | 30.5 bcdA |
| 4-yr VRE 0.095 mg/ml | 14.2 cdB | 11.0 cdB | 27.8 bcdA |
| VO 0.095 mg/ml | 9.7 dA | 8.6 cdA | 9.8 eA |
| 0.095% CTD | 12.8 dA | 8.0 dA | 11.8 eA |
| Sterile distilled water | 11.8 dA | 12.4 cdA | 15.2 deA |
a2-mon VRE = vetiver root ethanol extracts from greenhouse-grown, 2-mon-old cv. Sierra; 1-yr VRE = vetiver root ethanol extracts from field-grown, 1-year-old cv. Songkha 3; 4-yr VRE = vetiver root ethanol extracts from greenhouse-grown, 4-yr-old cv. Sierra; VO = commercial vetiver oil. Treatments were prepared from 1.0 mg/ml and 0.1 mg/ml extracts that were dissolved in a solvent of equal parts castor oil, Tween 80, and dimethyl sulfoxide (CTD) and then added to J2 suspensions in the wells. Final extract dilutions in the wells are presented in the table.
bValues are means of eight replications in each of the two trials, for a total of N = 16. Differences among treatments were determined by analysis of variance (ANOVA) and means were compared using Tukey-Kramer’s adjustment for multiple comparisons (P ⩽ 0.05). Similar lower case letters indicate that the means are not significantly different within a column; similar upper case letters indicate that the means are not significantly different within a row.