FLORAL FRAGRANCE VARIATION IN CYPRIPEDIUM - IMPLICATIONS FOR EVOLUTIONARY AND ECOLOGICAL-STUDIES

The floral fragrance compositions of eight species (including two puta tive varieties) of Cypripedium were determined by GC-mass spectrometry . Substantial diversity in fragrance compound skeletal type was detect ed and included benzenoid, terpenoid and fatty alcohol derivatives. Qu alitative fragrance variation was investigated within and between two populations of Cypripedium calceolus var. parviflorum. The clustering algorithm, unweighted pair group method arithmetic average (UPGMA) was used as an objective analytical means to assess population-level frag rance variation relative to species-level variation. Members from two populations of C. calceolus var. parviflorum formed a single cluster w ith similarity values ranging from 0.36 to 1.0, indicating a high degr ee of biogenetic uniformity among some individuals as well as substant ial relative divergence between others. The results of this study indi cate that conclusions about taxonomic or pollinator relationships, bas ed upon limited infraspecific sampling of floral fragrance, should be considered tentative until the extent of population variation is inves tigated. Copyright (C) 1997 Elsevier Science Ltd.