@article{Voulgari‐KokotaAnkenbrandGrimmeretal.2019,
  author    = {Voulgari-Kokota, Anna and Ankenbrand, Markus J. and Grimmer, Gudrun and Steffan-Dewenter, Ingolf and Keller, Alexander},
  title     = {Linking pollen foraging of megachilid bees to their nest bacterial microbiota},
  series = {Ecology and Evolution},
  volume    = {2019},
  journal   = {Ecology and Evolution},
  number    = {9},
  issn      = {00},
  doi       = {10.1002/ece3.5599},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201749},
  pages     = {10788-10800},
  year      = {2019},
  abstract  = {Solitary bees build their nests by modifying the interior of natural cavities, and they provision them with food by importing collected pollen. As a result, the microbiota of the solitary bee nests may be highly dependent on introduced materials. In order to investigate how the collected pollen is associated with the nest microbiota, we used metabarcoding of the ITS2 rDNA and the 16S rDNA to simultaneously characterize the pollen composition and the bacterial communities of 100 solitary bee nest chambers belonging to seven megachilid species. We found a weak correlation between bacterial and pollen alpha diversity and significant associations between the composition of pollen and that of the nest microbiota, contributing to the understanding of the link between foraging and bacteria acquisition for solitary bees. Since solitary bees cannot establish bacterial transmission routes through eusociality, this link could be essential for obtaining bacterial symbionts for this group of valuable pollinators.},
  language  = {en}
}
@article{VoulgariKokotaSteffanDewenterKeller2020,
  author    = {Voulgari-Kokota, Anna and Steffan-Dewenter, Ingolf and Keller, Alexander},
  title     = {Susceptibility of Red Mason Bee Larvae to Bacterial Threats Due to Microbiome Exchange with Imported Pollen Provisions},
  series = {Insects},
  volume    = {11},
  journal   = {Insects},
  number    = {6},
  issn      = {2075-4450},
  doi       = {10.3390/insects11060373},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207948},
  year      = {2020},
  abstract  = {Solitary bees are subject to a variety of pressures that cause severe population declines. Currently, habitat loss, temperature shifts, agrochemical exposure, and new parasites are identified as major threats. However, knowledge about detrimental bacteria is scarce, although they may disturb natural microbiomes, disturb nest environments, or harm the larvae directly. To address this gap, we investigated 12 Osmia bicornis nests with deceased larvae and 31 nests with healthy larvae from the same localities in a 16S ribosomal RNA (rRNA) gene metabarcoding study. We sampled larvae, pollen provisions, and nest material and then contrasted bacterial community composition and diversity in healthy and deceased nests. Microbiomes of pollen provisions and larvae showed similarities for healthy larvae, whilst this was not the case for deceased individuals. We identified three bacterial taxa assigned to Paenibacillus sp. (closely related to P. pabuli/amylolyticus/xylanexedens), Sporosarcina sp., and Bacillus sp. as indicative for bacterial communities of deceased larvae, as well as Lactobacillus for corresponding pollen provisions. Furthermore, we performed a provisioning experiment, where we fed larvae with untreated and sterilized pollens, as well as sterilized pollens inoculated with a Bacillus sp. isolate from a deceased larva. Untreated larval microbiomes were consistent with that of the pollen provided. Sterilized pollen alone did not lead to acute mortality, while no microbiome was recoverable from the larvae. In the inoculation treatment, we observed that larval microbiomes were dominated by the seeded bacterium, which resulted in enhanced mortality. These results support that larval microbiomes are strongly determined by the pollen provisions. Further, they underline the need for further investigation of the impact of detrimental bacterial acquired via pollens and potential buffering by a diverse pollen provision microbiome in solitary bees.},
  language  = {en}
}