Abstract：
BACKGROUND: The flowers of some species of orchids produce nectar as a reward for pollination, the process of transferring pollen from flower to flower. Epipactis albensis is an obligatory autogamous species, does not require the presence of insects for pollination, nevertheless, it has not lost the ability to produce nectar, the chemical composition of which we examined by gas chromatography-mass spectrometry (GC-MS) method for identification of potential insect attractants.
RESULTS: During five years of field research, we did not observe any true pollinating insects visiting the flowers of this species, only accidental insects as ants and aphids. As a result of our studies, we find that this self-pollinating orchid produces in nectar inter alia aliphatic saturated and unsaturated aldehydes such as nonanal (pelargonal) and 2-pentenal as well as aromatic ones (i.e., syringaldehyde, hyacinthin). The nectar is low in alkenes, which may explain the absence of pollinating insects. Moreover, vanillin and eugenol derivatives, well-known as important scent compounds were also identified, but the list of chemical compounds is much poorer compared with a closely related species, insect-pollinating E. helleborine.
CONCLUSIONS: Autogamy is a reproductive mechanism employed by many flowering plants, including the orchid genus Epipactis, as an adaptation to growing in habitats where pollinating insects are rarely observed due to the lack of nectar-producing plants they feed on. The production of numerous chemical attractants by self-pollinated E. albensis confirms the evolutionary secondary process, i.e., transition from ancestral insect-pollinating species to obligatory autogamous.
RESULTS: During five years of field research, we did not observe any true pollinating insects visiting the flowers of this species, only accidental insects as ants and aphids. As a result of our studies, we find that this self-pollinating orchid produces in nectar inter alia aliphatic saturated and unsaturated aldehydes such as nonanal (pelargonal) and 2-pentenal as well as aromatic ones (i.e., syringaldehyde, hyacinthin). The nectar is low in alkenes, which may explain the absence of pollinating insects. Moreover, vanillin and eugenol derivatives, well-known as important scent compounds were also identified, but the list of chemical compounds is much poorer compared with a closely related species, insect-pollinating E. helleborine.
CONCLUSIONS: Autogamy is a reproductive mechanism employed by many flowering plants, including the orchid genus Epipactis, as an adaptation to growing in habitats where pollinating insects are rarely observed due to the lack of nectar-producing plants they feed on. The production of numerous chemical attractants by self-pollinated E. albensis confirms the evolutionary secondary process, i.e., transition from ancestral insect-pollinating species to obligatory autogamous.
摘要：
背景：一些兰花的花产生花蜜作为授粉的奖励，花粉在花与花之间转移的过程。AlbensisEpipactisalbensis是一种强制性的自恋物种，不需要昆虫的存在进行授粉，然而，它没有失去产生花蜜的能力，我们通过气相色谱-质谱（GC-MS）方法检查了其化学成分，以鉴定潜在的昆虫引诱剂。
结果：在五年的实地研究中，我们没有观察到任何真正的授粉昆虫参观这个物种的花朵，只有偶然的昆虫像蚂蚁和蚜虫.作为我们研究的结果,我们发现这种自花授粉兰花在花蜜中产生，尤其是脂肪族饱和和不饱和醛，例如壬醛（pelargonal）和2-戊烯醛以及芳香族醛（即，丁香醛,风信子)。花蜜的烯烃含量低，这可以解释没有授粉昆虫。此外，香草醛和丁香酚衍生物，还鉴定了众所周知的重要气味化合物，但是与密切相关的物种相比，化合物的清单要差得多，昆虫授粉E.helleborine。
结论：Autogomy是许多开花植物采用的生殖机制，包括兰花属Epipactis，作为适应在栖息地中生长的一种适应，在这些栖息地中，由于缺乏以花蜜为食的生产植物，很少观察到授粉昆虫。自花授粉的阿尔伯斯产生了许多化学引诱剂，证实了进化的次要过程，即，从祖先的昆虫授粉物种过渡到强制性的自交。
结果：在五年的实地研究中，我们没有观察到任何真正的授粉昆虫参观这个物种的花朵，只有偶然的昆虫像蚂蚁和蚜虫.作为我们研究的结果,我们发现这种自花授粉兰花在花蜜中产生，尤其是脂肪族饱和和不饱和醛，例如壬醛（pelargonal）和2-戊烯醛以及芳香族醛（即，丁香醛,风信子)。花蜜的烯烃含量低，这可以解释没有授粉昆虫。此外，香草醛和丁香酚衍生物，还鉴定了众所周知的重要气味化合物，但是与密切相关的物种相比，化合物的清单要差得多，昆虫授粉E.helleborine。
结论：Autogomy是许多开花植物采用的生殖机制，包括兰花属Epipactis，作为适应在栖息地中生长的一种适应，在这些栖息地中，由于缺乏以花蜜为食的生产植物，很少观察到授粉昆虫。自花授粉的阿尔伯斯产生了许多化学引诱剂，证实了进化的次要过程，即，从祖先的昆虫授粉物种过渡到强制性的自交。
