Fig. 1.

Volatile emission from flowers of A. lyrata ssp. petraea. GC–MS chromatograms of volatiles collected from flowers of two individual plants 4A2 (a) and 2B1 (b) of a German A. lyrata ssp. petraea population (Plech). Volatiles were collected from six (a) or eight (b) detached flowers for 2 h (between 11 a.m. and 1 p.m.) in a closed-loop stripping system as described under “Materials and methods”. 1 benzaldehyde, 2 phenylacetaldehyde, 3 acetophenone, 4 nonanal, 5 decanal, S internal standard 1-bromodecane. Nonanal and decanal are background volatile contaminants. The chemical structures of benzaldehyde and phenylacetaldehyde are shown. c Emission rates of benzaldehyde and phenylacetaldehyde from different individuals of the Plech population. Calculations are based on volatile collections from three separate sets of flowers per plant