Abstract
The study included 15 lichen species analysed for volatile substances by
gas chromatography/mass spectrometry after collection by an adsorption
technique. We show that lichens emit characteristic blends of volatile
compounds, such as: fatty acid derivatives, isoprenoids and benzenoids.
We detected 104 volatiles, the most widespread being toluene and nonanal
(found in all 18 accessions), thereafter 1,4-xylene and β-pinene (17
accessions), decanal (16 accessions) and 3-methoxy-1,2-propanediol (15
accessions). 23 volatiles were restricted to just a single accession,
thus not informative in grouping the species. We did not find any clear
phylogenetic signal with respect to the mycobiont or the phycobiont. In
several cases, congeneric species displayed strongly divergent volatiles
spectra, indicating divergent selection. We discuss possible biotic
explanations for the observed volatiles diversity. Fruiting bodies of
lichens, so called apothecia, are often eaten by various small organisms
such as mites and collembola and one function of the volatiles could be
for protection or attraction. The present study connects to earlier work
on plant volatiles, insect pheromones and analytical techniques.