@article{ScheinerStraussThammetal.2020,
  author    = {Scheiner, Ricarda and Strauß, Sina and Thamm, Markus and Farr{\´e}-Armengol, Gerard and Junker, Robert R.},
  title     = {The bacterium Pantoea ananatis modifies behavioral responses to sugar solutions in honeybees},
  series = {Insects},
  volume    = {11},
  journal   = {Insects},
  number    = {10},
  issn      = {2075-4450},
  doi       = {10.3390/insects11100692},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216247},
  year      = {2020},
  abstract  = {1. Honeybees, which are among the most important pollinators globally, do not only collect pollen and nectar during foraging but may also disperse diverse microbes. Some of these can be deleterious to agricultural crops and forest trees, such as the bacterium Pantoea ananatis, an emerging pathogen in some systems. P. ananatis infections can lead to leaf blotches, die-back, bulb rot, and fruit rot. 2. We isolated P. ananatis bacteria from flowers with the aim of determining whether honeybees can sense these bacteria and if the bacteria affect behavioral responses of the bees to sugar solutions. 3. Honeybees decreased their responsiveness to different sugar solutions when these contained high concentrations of P. ananatis but were not deterred by solutions from which bacteria had been removed. This suggests that their reduced responsiveness was due to the taste of bacteria and not to the depletion of sugar in the solution or bacteria metabolites. Intriguingly, the bees appeared not to taste ecologically relevant low concentrations of bacteria. 4. Synthesis and applications. Our data suggest that honeybees may introduce P.ananatis bacteria into nectar in field-realistic densities during foraging trips and may thus affect nectar quality and plant fitness.},
  language  = {en}
}
@article{SchilcherThammStrubeBlossetal.2021,
  author    = {Schilcher, Felix and Thamm, Markus and Strube-Bloss, Martin and Scheiner, Ricarda},
  title     = {Opposing actions of octopamine and tyramine on honeybee vision},
  series = {Biomolecules},
  volume    = {11},
  journal   = {Biomolecules},
  number    = {9},
  issn      = {2218-273X},
  doi       = {10.3390/biom11091374},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246214},
  year      = {2021},
  abstract  = {The biogenic amines octopamine and tyramine are important neurotransmitters in insects and other protostomes. They play a pivotal role in the sensory responses, learning and memory and social organisation of honeybees. Generally, octopamine and tyramine are believed to fulfil similar roles as their deuterostome counterparts epinephrine and norepinephrine. In some cases opposing functions of both amines have been observed. In this study, we examined the functions of tyramine and octopamine in honeybee responses to light. As a first step, electroretinography was used to analyse the effect of both amines on sensory sensitivity at the photoreceptor level. Here, the maximum receptor response was increased by octopamine and decreased by tyramine. As a second step, phototaxis experiments were performed to quantify the behavioural responses to light following treatment with either amine. Octopamine increased the walking speed towards different light sources while tyramine decreased it. This was independent of locomotor activity. Our results indicate that tyramine and octopamine act as functional opposites in processing responses to light.},
  language  = {en}
}