Plant–pollinator interactions are mediated by floral signals and by the quantity and quality of floral rewards. Biotic and abiotic disturbances can influence plant reproductive success through both direct effects on plant performance and indirect effects on pollinator attraction. In this study, we examined the effects of drought on buckwheat (Fagopyrum esculentum Moensch), a globally cultivated plant that is prone to drought stress, dependent on insect pollinators for reproduction, and increasingly utilized in on‐farm conservation. Between drought‐stressed and control plants, we compared: nectar quantity and chemical composition, pollen quantity, floral volatile emissions, visits by both managed and wild pollinators, and plant reproductive success. Drought‐stressed plants produced significantly fewer flowers and less nectar per flower, though pollen quantity per flower was unaffected. Nectar from drought‐stressed plants had a lower proportion of sucrose relative to total sugars, though overall sugar concentration was unaffected. Significantly fewer bumble bees, honey bees, and flies were recorded on drought‐stressed plants. While there was no significant difference in the quantity of total floral volatile emissions, volatile compositions differed, with drought‐stressed plants having higher emissions of (Z)‐3‐hexenol, isobutyraldehyde, 2‐methylbutanal, and 3‐methylbutanal. Finally, drought stress had negative effects on seed set and total seed mass per plant. Our results show that drought stress can have significant effects on floral traits and pollinator attraction, reducing plant reproductive success, and the nectar resources available to pollinators. Thus, the potential value of this plant in pollinator conservation and as a honey plant may be reduced under drought stress.

中文翻译：

---

干旱胁迫会改变花卉的挥发物，并减少全球植物中的花卉奖励，传粉媒介活动和结实种子

植物-授粉媒介之间的相互作用是由花卉信号以及花卉奖励的数量和质量所介导的。生物和非生物干扰可以通过对植物生长的直接影响和对传粉媒介吸引力的间接影响来影响植物的繁殖成功。在这项研究中，我们研究了干旱对荞麦（Fagopyrum esculentum（Moensch），一种全球种植的植物，极易遭受干旱胁迫，依靠昆虫传粉媒介繁殖，并越来越多地用于农场保护中。在干旱植物和对照植物之间，我们比较了：花蜜的数量和化学成分，花粉的数量，花卉挥发物的排放，有管理的传粉者和野生传粉者的访问以及植物的繁殖成功。受干旱胁迫的植物产生的花少得多，每朵花的花蜜少，尽管每朵花的花粉量不受影响。尽管总糖浓度不受影响，但干旱胁迫植物的花蜜相对于总糖的蔗糖比例较低。在干旱胁迫的植物上记录到的大黄蜂，蜜蜂和苍蝇明显减少。Z）-3-己烯醇，异丁醛，2-甲基丁醛和3-甲基丁醛。最后，干旱胁迫对种子结实和单株总种子量有负面影响。我们的结果表明，干旱胁迫可能对花性状和授粉媒介吸引力产生显着影响，从而降低植物繁殖成功率，以及授粉媒介可获得的花蜜资源。因此，在干旱胁迫下，该植物在授粉媒介保护和作为蜂蜜植物中的潜在价值可能会降低。