Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Apdo. 1095, E-41080 Sevilla, Spain.
Phytochemistry. 2011 May;72(7):601-9. doi: 10.1016/j.phytochem.2011.02.001. Epub 2011 Mar 2.
Scent emission is important in nocturnal pollination systems, and plant species pollinated by nocturnal insects often present characteristic odor compositions and temporal patterns of emission. We investigated the temporal (day/night; flower lifetime) and spatial (different flower parts, nectar) pattern of flower scent emission in nocturnally pollinated Dianthusinoxianus, and determined which compounds elicit physiological responses on the antennae of the sphingid pollinator Hyles livornica. The scent of D.inoxianus comprises 68 volatile compounds, but is dominated by aliphatic 2-ketones and sesquiterpenoids, which altogether make up 82% of collected volatiles. Several major and minor compounds elicit electrophysiological responses in the antennae of H. livornica. Total odor emission does not vary along day and night hours, and neither does along the life of the flower. However, the proportion of compounds eliciting physiological responses varies between day and night. All flower parts as well as nectar release volatiles. The scent of isolated flower parts is dominated by fatty acid derivatives, whereas nectar is dominated by benzenoids. Dissection (= damage) of flowers induced a ca. 20-fold increase in the rate of emission of EAD-active volatiles, especially aliphatic 2-ketones. We suggest that aliphatic 2-ketones might contribute to pollinator attraction in D. inoxianus, even though they have been attributed an insect repellent function in other plant species. We also hypothesize that the benzenoids in nectar may act as an honest signal ('nectar guide') for pollinators.
气味散发对于夜间授粉系统非常重要，而由夜间昆虫授粉的植物物种通常具有特征性的气味组成和散发的时间模式。我们研究了夜间授粉的石竹属植物 Dianthusinoxianus 的花气味散发的时间（白天/夜晚；花的寿命）和空间（不同的花部分、花蜜）模式，并确定了哪些化合物会在鳞翅目传粉者 Sphingid 触角上引起生理反应。D.inoxianus 的香气由 68 种挥发性化合物组成，但以脂肪族 2-酮和倍半萜为主，总共占收集到的挥发物的 82%。几种主要和次要化合物会在 H. livornica 的触角上引起电生理反应。总气味散发量在白天和夜晚之间没有变化，在花朵的寿命期间也没有变化。然而，引起生理反应的化合物比例在白天和夜晚之间有所不同。所有的花部分以及花蜜都会释放挥发性物质。分离的花部分的气味主要由脂肪酸衍生物主导，而花蜜则以苯类化合物为主。花朵的解剖（= 损伤）导致 EAD 活性挥发物的释放速率增加约 20 倍，特别是脂肪族 2-酮。我们认为，脂肪族 2-酮可能有助于 D. inoxianus 中的传粉者吸引，尽管它们在其他植物物种中被归因于昆虫驱避功能。我们还假设花蜜中的苯类化合物可能作为传粉者的诚实信号（“花蜜指南”）。
