Table 6.
Oviposition inhibition activity of isobutyrylshikonin and isovalerylshikonin on Tetranychus urticae females.
| Dose (μg·cm−2) | Isobutyrylshikonin | Isovalerylshikonin | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Eggs/Female ± SD a | Inhibition Oviposition (% ± SD) b | ED50 (CI95) c | ED90 (CI95) c | Chi d | Eggs/Female ± SD a | Inhibition Oviposition (% ± SD) b | ED50 (CI95) c | ED90 (CI95) c | Chi d | |
| 13.5 | 2.6 ± 0.3 | 91.1 ± 3.2 | 2.71 (1.79–3.96) |
9.31 (8.97–15.56) |
2.524 | 0.3 ± 0.1 | 98.8 ± 2.1 | 1.15 (0.02–1.29) |
2.75 (2.38–3.34) |
2.253 |
| 6.8 | 4.3 ± 1.1 | 85.9 ± 5.5 | 0.9 ± 0.2 | 97.0 ± 3.5 | ||||||
| 3.4 | 11.2 ± 0.9 | 62.7 ± 4.3 | 2.5 ± 0.8 | 91.7 ± 2.8 | ||||||
| 1.7 | 19.3 ± 1.1 | 36.1 ± 4.6 | 7.5 ± 0.8 | 75.1 ± 3.1 | ||||||
| 0.8 | 28.4 ± 2.1 | 5.4 ± 0.9 | 21.6 ± 1.8 | 28.1 ± 1.7 | ||||||
| Control | 30.1 ± 4.5 | - | 30.1 ± 4.5 | - | ||||||
a Average number of eggs laid per female ± standard deviation (S.D.); b Mean inhibition of oviposition (in %) in comparison with the control ± standard deviation; c Effective dose ED50 (ED90) in μg·cm−2 causing 50% (90%) inhibition of egg laying by females T. urticae, compared with untreated control; CI95 = 95% confidence intervals, the activity is considered significantly different when the 95% CI fail to overlap; d Chi-square value, not significant at p > 0.05 level.