FLORAL FRAGRANCE DISPARITY BETWEEN 3 TAXA OF LADYSLIPPER CYPRIPEDIUM-CALCEOLUS (ORCHIDACEAE)

The flower fragrances of three geographically separated intraspecific orchid taxa of Cypripedium calceolus, viz. the Eurasian subspecies calceolus and the North American varieties parviflorum and pubescens, were isolated by sorption on synthetic polymers and analysed by GC-MS. The three taxa were found to have distinctly different fragrances composed mainly of fatty acid derivatives, isoprenoids, and phenyl derivatives, respectively. Sexual reproduction is dependent on the deception of pollinating solitary bees, and the three taxon-specific chemical compositions most probably reflect functional evolution in relation to different bee faunas. This study suggests that floral fragrance analysis provides a useful taxonomic tool in Cypripedium.