Floral scent emitted by white and coloured morphs in orchids.

摘要: Polymorphism of floral signals, such as colour and odour, is widespread in flowering plants often considered to be adaptive, reflecting various pollinator preferences for particular traits. Several authors have recently hypothesized that associations exist between scent, which would result from shared biochemistry these two In this study, we compared the chemical composition volatiles emitted by white- purple-flowered morphs three different orchid species, including food-deceptive species (Orchis mascula Orchis simia) a food-rewarding (Anacamptis coriophora fragrans). We found clear interspecific differences odours. As expected their pollination strategy, deceptive orchids showed high inter-individual variation volatiles, whereas A. c. fragrans low scent. Floral did not differ overall coloured-flowered O. fragrans, while simia exhibited volatile profiles morphs. However, detailed analysis restricted benzenoid compounds (which are associated with production anthocyanin pigments) white inflorescences more shikimic pathway than coloured ones, both simia. These results consistent current hypothesis creates pleiotropic links Whether intraspecific signals actually affects attraction influences reproductive success remains determined.