Laboratoire d'Ecologie Alpine, UMR CNRS 5553, Université Joseph Fourier, Grenoble, France.
New Phytol. 2010 Oct;188(2):451-63. doi: 10.1111/j.1469-8137.2010.03317.x. Epub 2010 Jun 9.
• Floral scents and visual cues of the globeflower Trollius europaeus may play a key role in the attraction of Chiastocheta flies, involved in a highly specific nursery pollination mutualism. • Here, headspace collection and GC-MS were used to identify and quantify the volatile organic compounds emitted by the globeflower. • Scents are produced in three different floral parts by four structures: secretory glands and flat epidermis cells in the abaxial sepal epidermis, conical cells in the adaxial sepal epidermis, and pollen. The blend is made up of 16 compounds commonly found in floral scents. Geographical variation among populations is low compared with variation amongst individuals within populations. Electroantenno-graphic analyses revealed that six compounds emitted by both anthers and sepals are detected by Chiastocheta flies. Removing the anthers hidden inside the globe from flowers in the field decreased the number of fly visits to globeflowers. • A multivariate analysis of the effect of several floral traits on pollinator visitation rate conducted in the field showed that both floral scents and visual flower cues play a role in pollinator attraction. However, their relative roles and the intensity of the selective pressures exerted on floral traits by pollinators appear to vary in time and space.
• 毛茛科银莲花属植物的花部气味和视觉线索可能在Chiastocheta 蝇吸引中起关键作用，Chiastocheta 蝇参与了高度特化的幼龄传粉互惠关系。 • 本研究采用顶空收集和 GC-MS 分析鉴定和量化了毛茛科银莲花属植物释放的挥发性有机化合物。 • 花朵的三个不同部位的四个结构产生气味：远轴萼片表皮的分泌腺和平坦表皮细胞、近轴萼片表皮的锥形细胞和花粉。该混合物由 16 种常见的花部气味化合物组成。与种群内个体间的变异相比，种群间的气味变异程度较低。触角电位分析显示，由花药和萼片释放的 6 种化合物被 Chiastocheta 蝇检测到。在野外，从花朵中去除隐藏在球体内的花药会减少蝇访问毛茛科银莲花的次数。 • 在野外进行的几种花部特征对传粉者访问率影响的多元分析表明，花部气味和视觉花朵线索都在传粉者吸引中起作用。然而，它们的相对作用以及传粉者对花部特征施加的选择压力的强度似乎随时间和空间而变化。
