Table 3.
Mean (± SE) emission rates (ng g−1 h−1) for the compounds with PLS-DA VIP scores over or equal to 1.0 for component 1. The C1 and C2 in brackets indicate VIP scores for component 1 and component 2, respectively. The main effects of ozone (O3), herbivory (HB), and their interaction (O3 × HB) were tested with generalised linear models. RI indicates retention indices of unknown compounds, and n the number of replicates. Simple main effects and interactions are emboldened. ns = P > 0.1
| AB | O3 | HB | O3+HB | Ozone (O3) | Herbivory (HB) | HB × O3 | |
|---|---|---|---|---|---|---|---|
| B. vulgaris | n = 4 | n = 4 | n = 4 | n = 4 | |||
| (E)-β-Ocimene (C1:1.6; C2:1.1) | 0.0 ± 0.0 | 1.1 ± 0.7 | 25.1 ± 5.9 | 16.5 ± 3.1 | ns | 0.022 | ns |
| (Z)-β-Ocimene (C1:1.5; C2:1.0) | 0.0 ± 0.0 | 1.5 ± 1.5 | 48.9 ± 11.5 | 38.5 ± 12.1 | ns | 0.057 | ns |
| (E)-DMNT (C1:1.3; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 140.3 ± 37.3 | 68.9 ± 35.6 | ns | < 0.001 | ns |
| α-Bergamotene (C1:1.2; C2:0.9) | 0.0 ± 0.0 | 0.4 ± 0.4 | 2.2 ± 0.8 | 1.2 ± 0.3 | ns | ns | ns |
| (E,E)-α-Farnesene (C1:1.0; C2:0.9) | 2.3 ± 0.9 | 6.9 ± 4.3 | 61.4 ± 17.0 | 23.6 ± 7.5 | ns | 0.084 | ns |
| B. nigra | n = 5 | n = 5 | n = 4 | n = 5 | |||
| (E)-DMNT (C1:1.5; C2:1.4) | 0.0 ± 0.0 | 3.0 ± 3.0 | 26.6 ± 21.9 | 32.3 ± 6.6 | ns | 0.090 | ns |
| Sesquiterpene RI 1530 (C1:1.4; C2:1.7) | 3.4 ± 1.2 | 6.4 ± 2.1 | 23.9 ± 8.9 | 53.3 ± 45.6 | ns | 0.008 | ns |
| Sesquiterpene RI 1347 (C1:1.4; C2:1.1) | 1.1 ± 0.3 | 1.9 ± 0.5 | 1.3 ± 0.1 | 2.2 ± 0.3 | ns | ns | ns |
| Sesquiterpene RI 1409 (C1:1.4; C2:1.1) | 1.1 ± 0.3 | 2.0 ± 0.6 | 1.8 ± 0.2 | 2.3 ± 0.3 | 0.029 | ns | ns |
| 3-Butenenitrile (C1:1.3; C2:1.4) | 0.9 ± 0.4 | 2.1 ± 1.1 | 14.5 ± 5.5 | 13.4 ± 4.4 | ns | 0.032 | ns |
| (Z)-γ-Bisabolene (C1:1.3; C2:1.0) | 0.2 ± 0.2 | 0.7 ± 0.2 | 0.5 ± 0.2 | 0.9 ± 0.1 | ns | ns | ns |
| 1,8-Anhydro-(E)-α-copaene-8-ol (C1:1.3; C2:1.0) | 1.5 ± 1.3 | 5.2 ± 2.5 | 4.2 ± 1.8 | 6.7 ± 1.0 | ns | ns | ns |
| (Z)-2-Hexenal (C1:1.3; C2:1.0) | 3.0 ± 3.0 | 9.3 ± 6.5 | 113.2 ± 31.0 | 38.3 ± 5.4 | ns | ns | ns |
| Caryophyllene (C1:1.3; C2:1.0) | 0.5 ± 0.3 | 3.4 ± 2.3 | 3.3 ± 1.5 | 3.8 ± 0.9 | ns | ns | ns |
| Hexanol (C1:1.2; C2:1.0) | 0.1 ± 0.1 | 0.3 ± 0.1 | 1.2 ± 0.2 | 0.8 ± 0.2 | ns | ns | ns |
| β-Pinene (C1:1.2; C2:1.0) | 0.3 ± 0.1 | 0.5 ± 0.1 | 0.3 ± 0.1 | 0.5 ± 0.1 | |||
| α-Longipinene (C1:1.1; C2:1.1) | 1.1 ± 0.4 | 2.7 ± 1.1 | 1.3 ± 0.5 | 2.8 ± 0.3 | ns | ns | ns |
| Sesquiterpene RI 1374 (C1:1.1; C2:1.1) | 3.0 ± 0.7 | 5.4 ± 1.6 | 3.7 ± 0.5 | 5.6 ± 0.6 | 0.013 | ns | ns |
| Allyl isothiocyanate (C1:1.0; C2:0.9) | 58.0 ± 24.9 | 57.9 ± 19.5 | 281.3 ± 88.9 | 285.5 ± 65.9 | ns | 0.008 | ns |
| S. arvensis | n = 5 | n = 5 | n = 3 | n = 4 | |||
| (E)-3-Hexenol (C1:1.6; C2:1.7) | 4.4 ± 3.6 | 10.4 ± 3.7 | 9.0 ± 4.2 | 17.4 ± 2.3 | ns | ns | ns |
| (E)-3-Hexenyl acetate (C1:1.6; C2:1.7) | 20.5 ± 15.8 | 29.2 ± 12.3 | 49.5 ± 29.9 | 75.3 ± 26.0 | ns | ns | ns |
| (Z)-2-Hexenal (C1:1.5; C2:1.4) | 5.6 ± 4.5 | 7.5 ± 4.1 | 16.6 ± 9.1 | 23.2 ± 5.4 | ns | ns | ns |
| Sesquiterpene RI 1411 (C1:1.4; C2:1.3) | 7.7 ± 3.4 | 13.1 ± 5.1 | 13.3 ± 6.5 | 16.8 ± 4.2 | ns | ns | ns |
| Caryophyllene (C1:1.4; C2:1.3) | 3.0 ± 2.0 | 14.4 ± 8.5 | 5.0 ± 2.4 | 3.8 ± 1.0 | ns | ns | ns |
| 1,8-Cineole (C1:1.2; C2:1.1) | 8.8 ± 8.8 | 18.0 ± 11.5 | 11.2 ± 6.1 | 42.1 ± 21.9 | ns | ns | ns |
| R. raphanistrum | n = 3 | n = 4 | n = 4 | n = 4 | |||
| Methyl sulfone (C1:1.6; C2:1.7) | 9.3 ± 5.2 | 0.3 ± 0.3 | 1.5 ± 1.1 | 0.0 ± 0.0 | ns | ns | ns |
| Sesquiterpene RI 1376 (C1:1.6; C2:1.4) | 0.0 ± 0.0 | 2.2 ± 0.9 | 0.6 ± 0.4 | 2.5 ± 0.2 | 0.086 | ns | ns |
| Sesquiterpene RI 1416 (C1:1.4; C2:1.1) | 0.0 ± 0.0 | 1.2 ± 0.7 | 1.9 ± 1.4 | 2.4 ± 0.3 | ns | ns | ns |
| (E)-DMNT (C1:1.4; C2:1.2) | 0.0 ± 0.0 | 0.0 ± 0.0 | 1.2 ± 1.2 | 6.2 ± 4.1 | ns | ns | ns |
| Caryophyllene (C1:1.3; C2:1.1) | 0.0 ± 0.0 | 0.2 ± 0.2 | 0.6 ± 0.4 | 2.0 ± 0.9 | ns | ns | ns |
| (E)-3-Hexenol (C1:1.3; C2:1.1) | 3.8 ± 3.8 | 25.6 ± 14.9 | 23.5 ± 8.7 | 34.6 ± 15.6 | ns | ns | ns |
| Dehydroaromadendrene (C1:1.3; C2:1.2) | 1.0 ± 1.0 | 5.5 ± 2.3 | 1.4 ± 0.8 | 5.4 ± 0.5 | ns | ns | ns |
| β-Pinene (C1:1.2; C2:1.0) | 0.0 ± 0.0 | 0.3 ± 0.2 | 0.2 ± 0.1 | 0.4 ± 0.2 | ns | ns | ns |
| Sesquiterpene RI 1386 (C1:1.2; C2:1.0) | 0.3 ± 0.3 | 1.1 ± 0.7 | 0.3 ± 0.3 | 1.2 ± 0.1 | ns | ns | ns |
| Δ-3-Carene (C1:1.1; C2:1.7) | 0.0 ± 0.0 | 0.1 ± 0.1 | 0.0 ± 0.0 | 0.2 ± 0.2 | 0.082 | ns | ns |
| B. juncea | n = 5 | n = 5 | n = 5 | n = 5 | |||
| β-Pinene (C1:2.9; C2:1.7) | 0.1 ± 0.1 | 0.4 ± 0.1 | 0.3 ± 0.1 | 0.5 ± 0.2 | ns | ns | ns |
| (Z)-2-Hexenal (C1:2.8; C2:1.6) | 0.0 ± 0.0 | 8.8 ± 8.8 | 5.3 ± 5.3 | 7.7 ± 3.7 | ns | ns | ns |
| Tert-Butyl isothiocyanate (C1:1.4; C2:1.0) | 12.5 ± 3.2 | 13.0 ± 3.6 | 15.7 ± 4.2 | 32.1 ± 14.2 | ns | 0.026 | ns |
| (E)-Ocimene (C1:1.3; C2:1.0) | 0.8 ± 0.6 | 2.0 ± 0.8 | 0.6 ± 0.6 | 3.6 ± 2.6 | ns | ns | ns |
| Benzonitrile (C1:1.3; C2:1.0) | 1.5 ± 0.8 | 0.9 ± 0.3 | 3.8 ± 1.7 | 0.5 ± 0.3 | ns | ns | ns |
| Sesquiterpene RI 1436 (C1:1.2; C2:1.5) | 0.4 ± 0.3 | 1.3 ± 0.4 | 1.5 ± 0.6 | 0.6 ± 0.4 | ns | ns | ns |
| Allyl isothiocyanate (C1:1.2; C2:0.9) | 3.1 ± 1.0 | 3.6 ± 0.8 | 6.1 ± 1.7 | 8.4 ± 3.7 | ns | 0.072 | ns |
| (E)-3-Hexenol (C1:1.1; C2:0.8) | 4.3 ± 1.4 | 5.7 ± 1.6 | 41.4 ± 28.2 | 12.5 ± 3.5 | 0.062 | 0.003 | 0.039 |
| Δ-3-Carene (C1:1.1; C2:1.0) | 2.3 ± 1.1 | 4.6 ± 1.8 | 3.4 ± 1.4 | 8.1 ± 6.0 | ns | ns | ns |
| B. napus | n = 5 | n = 5 | n = 5 | n = 5 | |||
| β-Myrcene (C1:1.7; C2:1.2) | 0.0 ± 0.0 | 0.2 ± 0.2 | 6.4 ± 1.3 | 6.7 ± 1.0 | ns | 0.006 | ns |
| (Z)-2-Hexenal (C1:1.5; C2:1.6) | 0.0 ± 0.0 | 0.0 ± 0.0 | 1.2 ± 1.2 | 5.8 ± 2.4 | ns | ns | ns |
| 1,8-Cineole (C1:1.4; C2:1.0) | 0.4 ± 0.2 | 0.6 ± 0.2 | 6.7 ± 1.3 | 10.5 ± 4.6 | ns | 0.051 | ns |
| α-Selinene (C1:1.3; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 9.1 ± 3.7 | 5.6 ± 0.5 | ns | < 0.001 | ns |
| (E)-DMNT (C1:1.3; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 176.9 ± 14.0 | 117.6 ± 36.2 | ns | < 0.001 | ns |
| Sesquiterpene RI 1438 (C1:1.3; C2:1.0) | 0.1 ± 0.1 | 0.2 ± 0.2 | 2.7 ± 0.3 | 1.4 ± 0.6 | ns | < 0.001 | ns |
| (E,E)-α-Farnesene (C1:1.3; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 9.2 ± 2.4 | 4.6 ± 0.8 | ns | <0.001 | ns |
| α-Thujene (C1:1.2; C2:0.8) | 0.2 ± 0.2 | 0.3 ± 0.2 | 4.8 ± 0.9 | 5.6 ± 0.7 | ns | 0.050 | ns |
| Menthol (C1:1.1; C2:1.2) | 4.4 ± 2.9 | 2.1 ± 1.3 | 5.3 ± 5.3 | 0.0 ± 0.0 | ns | ns | ns |
| β-Pinene (C1:1.1; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 1.1 ± 0.2 | 1.0 ± 0.2 | ns | 0.030 | ns |
| Sesquiterpene RI 1506 (C1:1.1; C2:1.0) | 0.0 ± 0.0 | 0.0 ± 0.0 | 2.9 ± 0.8 | 1.7 ± 0.3 | ns | < 0.001 | ns |
| (E)-3-Hexenol (C1:1.0; C2:1.0) | 0.0 ± 0.0 | 0.0 ± 0.0 | 11.5 ± 2.4 | 9.5 ± 2.6 | ns | < 0.001 | ns |
| S. alba | n = 5 | n = 4 | n = 4 | n = 5 | n = 5 | ||
| Sabinene (C1:1.6; C2:1.4) | 0.0 ± 0.0 | 0.0 ± 0.0 | 1.3 ± 0.5 | 3.4 ± 0.5 | ns | < 0.001 | ns |
| α-Pinene (C1:1.6; C2:1.7) | 0.0 ± 0.0 | 1.2 ± 0.7 | 0.5 ± 0.5 | 1.1 ± 0.3 | ns | ns | ns |
| (E)-DMNT (C1:1.5; C2:1.2) | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.9 ± 0.9 | 2.0 ± 0.8 | ns | 0.055 | ns |
| 1,8-Cineole (C1:1.4; C2:1.2) | 0.1 ± 0.1 | 5.2 ± 5.2 | 0.7 ± 0.3 | 2.2 ± 0.4 | ns | ns | ns |
| Germacrene-D (C1:1.4; C2:1.3) | 0.0 ± 0.0 | 0.0 ± 0.0 | 12.4 ± 2.9 | 16.4 ± 5.5 | ns | < 0.001 | ns |
| Hexanal (C1:1.1; C2:1.0) | 0.1 ± 0.1 | 1.1 ± 0.7 | 1.2 ± 0.7 | 17.1 ± 6.0 | ns | ns | ns |
| Methyl salicylate (C1:1.0; C2:0.9) | 0.0 ± 0.0 | 0.0 ± 0.0 | 1.1 ± 0.9 | 1.8 ± 0.8 | ns | 0.050 | ns |
| R. sativus | n = 5 | n = 4 | n = 5 | n = 4 | |||
| (Z)-β-ocimene (C1:2.0; C2:1.9) | 2.9 ± 0.6 | 0.4 ± 0.4 | 6.3 ± 0.9 | 5.2 ± 1.2 | ns | ns | ns |
| β-Pinene (C1:1.7; C2:1.5) | 0.0 ± 0.0 | 1.9 ± 0.9 | 2.6 ± 2.6 | 2.3 ± 1.0 | ns | ns | ns |
| (E)-DMNT (C1:1.5; C2:1.3) | 0.0 ± .0.0 | 0.0 ± 0.0 | 8.3 ± 3.1 | 36.5 ± 9.5 | ns | ns | ns |
| Methyl isothiocyanate (C1:1.2; C2:1.1) | 7.0 ± 2.3 | 4.0 ± 2.2 | 5.7 ± 0.8 | 4.9 ± 3.3 | ns | ns | ns |
| Limonene (C1:1.2; C2:1.2) | 0.2 ± 0.2 | 0.7 ± 0.7 | 0.0 ± 0.0 | 1.1 ± 0.5 | ns | ns | ns |
| Δ-3-Carene (C1:1.1; C2:1.0) | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.2 ± 0.1 | 0.6 ± 0.3 | ns | 0.099 | ns |