| Title: | Subtle Chemical Variations with Strong Ecological Significance: Stereoselective Responses of Male Orchid Bees to Stereoisomers of Carvone Epoxide |
| Author(s): | Brandt K; Dotterl S; Fuchs R; Navarro D; Machado ICS; Dobler D; Reiser O; Ayasse M; Milet-Pinheiro P; |
| Address: | "Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany. Department of Biosciences, University of Salzburg, Salzburg, Austria. Departamento de Quimica Fundamental, Universidade Federal de Pernambuco, Recife, Brazil. Departamento de Botanica, Universidade Federal de Pernambuco, Recife, Brazil. Institute of Organic Chemistry, University of Regensburg, Regensburg, Germany. Departamento de Botanica, Universidade Federal de Pernambuco, Recife, Brazil. miletpinheiro@hotmail.com" |
| DOI: | 10.1007/s10886-019-01072-6 |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
| Abstract: | "Different enantiomers of chiral compounds within floral perfumes usually trigger distinct responses in insects; however, this has frequently been neglected in studies investigating semiochemicals in plant-pollinator interactions. Approximately 1000 neotropical plants produce floral perfumes as the only reward for pollinators, i.e. male euglossine bees. The chiral compound carvone epoxide is a key component of the scent bouquet of many perfume-rewarding plants that are pollinated by males of Eulaema. Here, we tested the biological activity of the four carvone epoxide stereoisomers to four Eulaema species occurring in the Atlantic Rainforest of NE-Brazil. We determined the stereochemistry of carvone epoxide in the floral scent of several Catasetum species, tested whether the antennae of bees respond differentially to these stereoisomers and investigated if there is a behavioural preference for any of the stereoisomers. We found that 1) Catasetum species emit only the (-)-trans-stereoisomer of carvone epoxide, 2) for E. atleticana and E. niveofasciata antennal responses to the (-)-trans-carvone epoxide were significantly stronger than those to (-)-cis-carvone epoxide, 3) the strength and pattern of antennal responses to all 4 stereoisomers (separately tested) did not differ among Eulaema species, and 4) there were significant differences in attractiveness of the four stereoisomers to the bees species with the (-)-trans-stereoisomer being particularly attractive. We assume (-)-trans-carvone epoxide to be the dominant isomer in perfume-rewarding plants pollinated by Eulaema. The universal occurrence of carvone epoxide in Catasetum species pollinated by Eulaema, suggests that this compound has evolved in perfume-rewarding as a specific attractant for Eulaema bees as pollinators" |
| Keywords: | "Animals Bees/*physiology Behavior, Animal/drug effects Chromatography, Gas Cyclohexane Monoterpenes Epoxy Compounds/chemistry Flowers/chemistry/metabolism Male Monoterpenes/*chemistry/pharmacology Orchidaceae/chemistry/metabolism Stereoisomerism Catasetum;" |
| Notes: | "MedlineBrandt, Katharina Dotterl, Stefan Fuchs, Roman Navarro, Daniela Maria do Amaral Ferraz Machado, Isabel Cristina Sobreira Dobler, Daniel Reiser, Oliver Ayasse, Manfred Milet-Pinheiro, Paulo eng (AY 12/12-1)/Deutsche Forschungsgemeinschaft/ 57210526/Deutscher Akademischer Austauschdienst/ Finance Code 001/Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior/ BCT - 0288-2.05/17/Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco/ CNPq/PDJ -152077/2016-2/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (BR)/ 2019/05/22 J Chem Ecol. 2019 Jun; 45(5-6):464-473. doi: 10.1007/s10886-019-01072-6. Epub 2019 May 21" |
