Aldehyde volatiles emitted in succession from mechanically damaged leaves of poplar cuttings

摘要

Plant aldehydes are volatiles necessary to defenses against environmental stress. To explore their emissions in response to wounding, we performed gas chromatography-mass spectrometry (GC-MS) on cuttings from poplar (Populus simonii x P. pyramidalis 'Opera 8277) that were mechanically damaged to mimic herbivore attack. We detected 16 aldehydes, including 11 linear saturated alldehydes, 3 linear unsaturated alldehydes, and 2 non-linear aldehydes. Emissions of these aldehydes were clearly enhanced by such treatment, and exhibited a similar pattern of change, i.e., increasing in the first 2 h, then sharply decreasing before rising again at about 12 h. Two release peaks for these alldehydes were observed. Therefore, we propose two pathways for the mediation of aldehyde emissions following damage. The first peak may represent emissions from plant storage pools, whereas the second release peak might result from greater formation de novo through an activated synthesis pathway.