The sesquiterpene alpha-copaene is induced in tomato leaves infected by Botrytis cinerea

Explorative experiments were done to investigate the possibility that tomato plants infected by Botrytis cinerea have a different emission of volatile organic compounds (VOC) than healthy plants. This was done by headspace analysis of volatiles emitted by detached leaves of infected and healthy plants. Principal component analysis (PCA) of GC-FID chromatograms revealed clearly separated clusters between infected and control leaves and identification of an interesting compound. In further analysis by GC-MS, the significantly distinctive component (p <= 0.05) was identified as the sesquiterpene alpha-copaene. In previous work on herbivore damage, alpha-copaene was not distinctive, which may suggest that alpha-copaene may be specifically associated to fungal infections in tomato.