Institute of Experimental Ecology, University of Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2013 Sep;199(9):751-61. doi: 10.1007/s00359-013-0835-5. Epub 2013 Jun 21.
Specialist and generalist bees use olfactory and visual cues to find and recognise flowering plants. Specialised (oligolectic) bees rely on few host plants for pollen collection. These bee species are suggested to use specific volatiles, but it is unknown whether they have dedicated adaptations for these particular compounds compared to bees not specialised on the same plants. In the present study, we investigated the perception of host odorants and its neuronal substrate with regard to host-plant finding behaviour in oligolectic bees. We reconstructed the antennal lobes (AL) in the Salix specialist, Andrena vaga, and counted about 135 glomeruli and thereby less than the approximately 160 in honeybees. Using calcium imaging experiments to measure neural activity in the bee brain, we recorded odorant-evoked activity patterns in the AL of A. vaga and, for comparison, in the generalist honeybee, Apis mellifera. Our physiological experiments demonstrated that A. vaga bees were particularly sensitive to 1,4-dimethoxybenzene, a behaviour-mediating odorant of Salix host flowers. We found more sensitive glomeruli in the specialised bees as compared to generalist honeybees. This neural adaptation might allow oligolectic A. vaga bees to effectively locate host plants from distances.
专业蜂和通用蜂利用嗅觉和视觉线索来寻找和识别开花植物。专门化（寡食性）的蜜蜂依赖少数几种花粉收集的宿主植物。这些蜜蜂物种被认为使用特定的挥发物，但尚不清楚它们是否与不专门针对同一植物的蜜蜂相比，对这些特定化合物具有专门的适应能力。在本研究中，我们研究了寡食性蜜蜂在寻找宿主植物行为中对宿主气味的感知及其神经元基质。我们重建了柳属专家 Andrena vaga 的触角叶（AL），并计算出约 135 个神经节，而不是大约 160 个在蜜蜂中。使用钙成像实验来测量蜜蜂大脑中的神经活动，我们记录了 A. vaga 的 AL 中的气味诱发活动模式，并进行了比较，在通用的蜜蜂 Apis mellifera 中。我们的生理实验表明，A. vaga 蜜蜂对 1,4-二甲氧基苯特别敏感，这是柳属宿主花的一种行为介导气味。与通用的蜜蜂相比，我们在专门化的蜜蜂中发现了更敏感的神经节。这种神经适应可能使寡食性的 A. vaga 蜜蜂能够有效地从远处定位宿主植物。
