Rossoni Sergio, Parkinson Rachel H, Niven Jeremy E, Nicholls Elizabeth
Department of Ecology and Evolution, University of Sussex, Brighton, East Sussex, UK.
Department of Biology, University of Oxford, Oxford, Oxfordshire, UK.
R Soc Open Sci. 2025 May 7;12(5):250465. doi: 10.1098/rsos.250465. eCollection 2025 May.
Bees rely on amino acids from nectar and pollen for essential physiological functions. While nectar typically contains low (less than 1 mM) amino acid concentrations, levels in pollen are higher but variable (10-200 mM). Behavioural studies suggest bumblebees have preferences for specific amino acids but whether such preferences are mediated via gustatory mechanisms remains unclear. This study explores bumblebees' () gustatory sensitivity to two essential amino acids found in nectar and pollen, valine and lysine, using electrophysiological recordings from gustatory sensilla on their mouthparts. Valine elicited a concentration-dependent response from 0.1 mM, indicating that bumblebees could perceive valine at concentrations found naturally in nectar and pollen. By contrast, lysine failed to evoke a response across tested concentrations (0.1-500 mM). The absence of lysine detection raises questions about the specificity and diversity of amino acid-sensitive receptors in bumblebees. Bees responded to valine at lower concentrations than sucrose, suggesting comparatively higher sensitivity (EC: 0.7 mM versus 3.91 mM for sucrose). Our findings indicate that bumblebees can evaluate the amino acid content of pollen and nectar using pre-ingestive cues, rather than relying on post-ingestive cues or feedback from their nestmates. Such sensory capabilities probably impact foraging strategies, with implications for plant-bee interactions and pollination.
蜜蜂依靠花蜜和花粉中的氨基酸来维持基本的生理功能。虽然花蜜中的氨基酸浓度通常较低（低于1毫摩尔/升），但花粉中的氨基酸水平较高且存在差异（10 - 200毫摩尔/升）。行为学研究表明，大黄蜂对特定氨基酸有偏好，但这种偏好是否通过味觉机制介导仍不清楚。本研究利用对大黄蜂口器味觉感受器的电生理记录，探索了大黄蜂对花蜜和花粉中发现的两种必需氨基酸缬氨酸和赖氨酸的味觉敏感性。缬氨酸从0.1毫摩尔/升开始引发浓度依赖性反应，这表明大黄蜂能够感知花蜜和花粉中天然存在浓度的缬氨酸。相比之下，赖氨酸在所有测试浓度（0.1 - 500毫摩尔/升）下均未引发反应。无法检测到赖氨酸引发了关于大黄蜂中氨基酸敏感受体的特异性和多样性的问题。蜜蜂对缬氨酸的反应浓度低于蔗糖，表明其敏感性相对较高（缬氨酸的半最大效应浓度为0.7毫摩尔/升，而蔗糖为3.91毫摩尔/升）。我们的研究结果表明，大黄蜂可以利用摄食前的线索来评估花粉和花蜜中的氨基酸含量，而不是依赖摄食后的线索或巢友的反馈。这种感官能力可能会影响觅食策略，对植物与蜜蜂的相互作用和授粉产生影响。
