Table 6.
The major VOCs identified in red pine needles according to contribution plot (weight > 1.0) list of OPLS-DA derived score plot
| Class according to Ca/Cb ratio | Compound Name | Chemical Class | Score Contrib (Group - Average), Weight=p1p2 |
| Class 1 | 1-Penten-3-ol | alkene | 2.50226 |
| (Intact Needle) | 2-Ethyl furan | heterocyclics | 2.28275 |
| L-Bornyl acetate | monoterpene | 1.90871 |
| (Z)-3-Hexen-1-ol | alkene | 1.25681 |
| Bicyclogermacrene | sesquiterpene | 1.09741 |
| Cyclohexene oxide | alkene | 1.0649 |
| Germacrene-D | sesquiterpene | 1.02957 |
| Class 2 | 2-Heptenal | alkene | 2.04603 |
| (Senescent Needle) | β-Myrcene | monoterpene | 1.68568 |
| 3-Methyl-2-buten-1-ol | alkene | 1.57739 |
| Spathulenol | sesquiterpene | 1.38274 |
| Class 3 | Camphor | monoterpene | 2.09959 |
| (Litter Needle) | Pinocarvone | monoterpene | 1.68045 |
| Myrtenol | monoterpene | 1.46641 |
| Caryophyllene oxide | sesquiterpene | 1.4.508 |
| p-Cymenene | monoterpene | 1.32866 |
| p-Cymene | monoterpene | 1.32645 |