Title: | The impact of biochemistry vs. population membership on floral scent profiles in colour polymorphic Hesperis matronalis |
Author(s): | Majetic CJ; Raguso RA; Ashman TL; |
Address: | "Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA. cmajetic@allegheny.edu" |
ISSN/ISBN: | 1095-8290 (Electronic) 0305-7364 (Print) 0305-7364 (Linking) |
Abstract: | "BACKGROUND AND AIMS: Studies of floral scent evolution often attribute variation in floral scent to differences in pollinator behaviour, ignoring the potential for shared biochemistry between floral scent and floral colour to dictate patterns of phenotypic variation in scent production. To determine the relative effects of shared biochemistry and/or localized population-level phenomena on floral scent phenotype, floral scent composition and emission rate were examined in five wild populations of colour polymorphic Hesperis matronalis (Brassicaceae). METHODS: Floral scent was collected by in situ dynamic headspace extraction on purple and white colour morphs in each of five wild populations. Gas chromatography-mass spectroscopy of extracts allowed determination of floral scent composition and emission rate for all individuals, which were examined by non-metric multidimensional scaling and analysis of variance (ANOVA), respectively, to determine the contributions of floral colour and population membership to scent profile variation. KEY RESULTS: Despite the fact that colour morph means were very similar in some populations and quite different in other populations, colour morphs within populations did not differ from each other in terms of scent composition or emission rate. Populations differed significantly from one another in terms of both floral scent composition and emission rate. CONCLUSIONS: Shared biochemistry alone cannot explain the variation in floral scent phenotype found for H. matronalis. Such a result may suggest that the biochemical association between floral scent and floral colour is complex or dependent on genetic background. Floral scent does vary significantly with population membership; several factors, including environmental conditions, founder effects and genetics, may account for this differentiation and should be considered in future studies" |
Keywords: | "Analysis of Variance *Biochemistry Brassicaceae/*physiology Flowers/*physiology Models, Biological *Odorants Pigmentation/*physiology Population Dynamics;" |
Notes: | "MedlineMajetic, Cassie J Raguso, Robert A Ashman, Tia-Lynn eng Comparative Study Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England 2008/09/30 Ann Bot. 2008 Dec; 102(6):911-22. doi: 10.1093/aob/mcn181. Epub 2008 Sep 26" |