Department of Environment and Biodiversity, Paris Lodron University of Salzburg, 5020, Salzburg, Austria.
Department of Limnology, University of Kassel, 34127, Kassel, Germany.
Sci Rep. 2022 Mar 24;12(1):5086. doi: 10.1038/s41598-022-08196-y.
Insect-pollinated plants often release complex mixtures of floral scents to attract their pollinators. Yet scent compounds eliciting physiological or behavioural responses in pollinators have only been identified in few plant species. The sapromyiophilous aroid Arum maculatum releases a highly diverse dung-like scent with overall more than 300 different compounds recorded so far to attract its psychodid and other fly pollinators. The volatiles' role in pollinator attraction is mostly unknown. To identify potential behaviourally active compounds, we recorded electroantennographic responses of four Psychodidae and one Sphaeroceridae species to (1) inflorescence scents of A. maculatum and (2) the scents released by cow dung, likely imitated by the plant species. Here we show that these flies are sensitive to 78 floral volatiles of various chemical classes, 18 of which were also found in cow dung. Our study, which for the first time determined physiologically active compounds in the antennae of Psychoda spp. and Sphaeroceridae, identified various volatiles not known to be biologically active in any floral visitors so far. The obtained results help deciphering the chemical basis that enables A. maculatum and other plants, pollinated by psychodids and sphaerocerids, to attract and deceive their pollinators.
传粉昆虫的植物通常会释放复杂的花香混合物来吸引传粉者。然而，在少数植物物种中，只鉴定出了能引起传粉者生理或行为反应的气味化合物。食腐性天南星科植物 Arum maculatum 释放出高度多样化的类似粪便的气味，到目前为止，已经记录到超过 300 种不同的化合物，以吸引其双翅目和其他蝇类传粉者。挥发物在传粉者吸引中的作用大多未知。为了鉴定潜在的行为活性化合物，我们记录了四种双翅目和一种鳞翅目物种对（1）Arum maculatum 花序气味和（2）可能被植物模仿的牛粪释放气味的触角电生理反应。在这里，我们表明这些苍蝇对各种化学类别的 78 种花香挥发物敏感，其中 18 种也存在于牛粪中。我们的研究首次确定了 Psychoda spp. 和鳞翅目触角中的生理活性化合物，鉴定出了各种迄今为止在任何花卉访客中都没有被认为具有生物活性的挥发物。获得的结果有助于破译使 Arum maculatum 和其他由双翅目和鳞翅目授粉的植物能够吸引和欺骗其传粉者的化学基础。
