| Title: | Floral scent in a sexually deceptive Ophrys orchid: from headspace collections to solvent extractions |
| Author(s): | Zito P; Rosselli S; Bruno M; Maggio A; Sajeva M; |
| Address: | "a Department of Biological, Chemical and Pharmaceutical Sciences and Technologies , University of Palermo , Palermo , Italy. b Department of Agricultural, Food and Forest Sciences , University of Palermo , Palermo , Italy" |
| DOI: | 10.1080/15592324.2018.1552056 |
| ISSN/ISBN: | 1559-2324 (Electronic) 1559-2316 (Print) 1559-2316 (Linking) |
| Abstract: | "Sexually deceptive orchid flowers use visual, tactile and olfactory cues of female insects in order to attract males of one or a few closely related species as pollinators. Ophrys L. is the most species-rich genus of sexually deceptive orchids in the Mediterranean Basin. Despite Ophrys pollinated by Andrena male bees use alkanes and mainly alkenes with specific double-bond positions as key signals that trigger pseudocopulatory behavior, some volatile organic compounds (VOCs) with low molecular weight were found as long-range attractants non-eliciting copulatory behavior. Since floral scents in Ophrys have been extensively studied by solvent extractions here we aimed to understand which floral volatiles are found when two different collection methods are used in Ophrys panormitana flowers. By knowing their chemical composition, we could better understand the scent chemistry of this Ophrys species without overlooking VOCs which could also have a function in its pollination biology. Scent samples collected by dynamic headspace and by solvent extraction were analyzed by gas chromatography/mass spectrometry (GC/MS). The floral scent of O. panormitana is composed by a bouquet of VOCs with lower and higher molecular weights. The headspace samples contained VOCs with higher volatility (mainly one aliphatic alcohol and two aliphatic ketones) whereas the solvent extracts were composed by VOCs with lower volatility (exclusively long-chain alkanes and alkenes). Overlapping in VOCs between headspace and solvent samples were not found. For the first time Andrena nigroaenea was observed during the pseudocopulation and removing the pollinaria of a flower of O. panormitana. Abbreviations: VOCs, volatile organic compounds; GC/MS, gas chromatography-mass spectrometry; KRI, Kovats Retention Indices" |
| Keywords: | Flowers/metabolism Gas Chromatography-Mass Spectrometry Odorants Orchidaceae/*metabolism Pollination/physiology Volatile Organic Compounds/analysis/*metabolism Andrena Ophrys panormitana Orchidaceae pollination volatile organic compounds; |
| Notes: | "MedlineZito, Pietro Rosselli, Sergio Bruno, Maurizio Maggio, Antonella Sajeva, Maurizio eng Research Support, Non-U.S. Gov't 2018/12/07 Plant Signal Behav. 2019; 14(1):1552056. doi: 10.1080/15592324.2018.1552056. Epub 2018 Dec 3" |
