, Volume 45, Issue 4, pp 467–477 | Cite as

Density-dependent negative responses by bumblebees to bacteria isolated from flowers

  • Robert R. JunkerEmail author
  • Tanja Romeike
  • Alexander Keller
  • Daniela Langen
Original article


Flowers offer habitats for bacterial communities that are often characterized by low diversities but high densities. The composition of these communities and the dissemination of bacteria between flowers receive increasing attention, whereas the ecological functions of flower-associated but non-phytopathogenic bacteria remain understudied. We screened bacteria isolated from nectar, petals and leaves of two plant species for their potential to affect flower–visitor interactions. We took advantage of the proboscis extension reflex (PER) of bumblebees evoked by sugar and investigated whether bacteria associated with the reward may interrupt this reflex. Cultivated bacteria were transferred into a watery glucose solution in increasing densities and their effect on the proportion of bumblebees displaying the PER after antennal contact with glucose solutions and bacteria was scored. In all but one trial, the proportion of bumblebees that accepted the watery glucose solution was negatively correlated with the bacterial density. Nearly half of the bacteria tested evoked avoidance at naturally occurring densities. Our results suggest that bacteria colonizing flowers have the potential to negatively affect the reproduction of plants via reduced visits by pollinators.


aversion Bacilli Bombus terrestris plant–bacteria–animal interactions proboscis extension reflex 



We thank Christina Loewel for helpful advices and Karl Köhrer for technical support. The project was supported by the Deutsche Forschungsgemeinschaft (DFG, JU 2856/1-1).


  1. Adler, L.S. (2000) The ecological significance of toxic nectar. Oikos 91, 409–420CrossRefGoogle Scholar
  2. Alvarez-Perez, S., Herrera, C.M. (2013) Composition, richness and nonrandom assembly of culturable bacterial-microfungal communities in floral nectar of Mediterranean plants. FEMS Microbiol. Ecol. 83, 685–699PubMedCrossRefGoogle Scholar
  3. Alvarez-Perez, S., Herrera, C.M., de Vega, C. (2012) Zooming-in on floral nectar: a first exploration of nectar-associated bacteria in wild plant communities. FEMS Microbiol. Ecol. 80, 591–602PubMedCrossRefGoogle Scholar
  4. Anfora, G., Rigosi, E., Frasnelli, E., Ruga, V., Trona, F., Vallortigara, G. (2011) Lateralization in the invertebrate brain: left-right asymmetry of olfaction in bumble bee, Bombus terrestris. Plos One 6, e18903PubMedCentralPubMedCrossRefGoogle Scholar
  5. Belisle, M., Peay, K.G., Fukami, T. (2012) Flowers as islands: spatial distribution of nectar-inhabiting microfungi among plants of Mimulus aurantiacus, a hummingbird-pollinated shrub. Microb. Ecol. 63, 711–718PubMedCrossRefGoogle Scholar
  6. Brysch-Herzberg, M. (2004) Ecology of yeasts in plant–bumblebee mutualism in Central Europe. FEMS Microbiol. Ecol. 50, 87–100PubMedCrossRefGoogle Scholar
  7. Buban, T., Orosz-Kovacs, Z., Farkas, A. (2003) The nectary as the primary site of infection by Erwinia amylovora (Burr.). Plant Syst. Evol. 238, 183–194Google Scholar
  8. Carter, C., Thornburg, R.W. (2004) Is the nectar redox cycle a floral defense against microbial attack? Trends Plant Sci. 9, 320–324PubMedCrossRefGoogle Scholar
  9. Crawley M. J. (2005) Statistics - An introduction using R. John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England.Google Scholar
  10. Davis, T.S., Crippen, T.L., Hofstetter, R.W., Tomberlin, J.K. (2013) Microbial volatile emissions as insect semiochemicals. J. Chem. Ecol. 39, 840–859PubMedCrossRefGoogle Scholar
  11. Ercolani, G.L. (1991) Distribution of epiphytic bacteria on olive leaves and the influence of leaf age and sampling time. Microb. Ecol. 21, 35–48PubMedCrossRefGoogle Scholar
  12. Evangelista, C., Kraft, P., Dacke, M., Reinhard, J., Srinivasan, M.V. (2010) The moment before touchdown: landing manoeuvres of the honeybee Apis mellifera. J. Exp. Biol. 213, 262–270PubMedCrossRefGoogle Scholar
  13. Ezenwa, V.O., Gerardo, N.M., Inouye, D.W., Medina, M., Xavier, J.B. (2012) Animal behavior and the microbiome. Science 338, 198–199PubMedCrossRefGoogle Scholar
  14. Fouks, B., Lattorff, H.M.G. (2011) Recognition and avoidance of contaminated flowers by foraging bumblebees (Bombus terrestris). Plos One 6, e26328PubMedCentralPubMedCrossRefGoogle Scholar
  15. Fridman, S., Izhaki, I., Gerchman, Y., Halpern, M. (2012) Bacterial communities in floral nectar. Environ. Microbiol. Rep. 4, 97–104PubMedCrossRefGoogle Scholar
  16. Fuernkranz, M., Lukesch, B., Müller, H., Huss, H., Grube, M., Berg, G. (2012) Microbial diversity inside pumpkins: microhabitat-specific communities display a high antagonistic potential against phytopathogens. Microb. Ecol. 63, 418–428CrossRefGoogle Scholar
  17. Haupt, S.S. (2004) Antennal sucrose perception in the honey bee (Apis mellifera L.): behaviour and electrophysiology. J. Comp. Physiol. A Neuroethol. Sens. Neural. Behav. Physiol. 190, 735–745PubMedCrossRefGoogle Scholar
  18. Herrera, C.M., Garcia, I.M., Perez, R. (2008) Invisible floral larcenies: microbial communities degrade floral nectar of bumble bee-pollinated plants. Ecology 89, 2369–2376PubMedCrossRefGoogle Scholar
  19. Herrera, C.M., Pozo, M.I., Medrano, M. (2013) Yeasts in nectar of an early-blooming herb: sought by bumble bees, detrimental to plant fecundity. Ecology 94, 273–279PubMedCrossRefGoogle Scholar
  20. Huang, M., Sanchez-Moreiras, A.M., Abel, C., Sohrabi, R., Lee, S., Gershenzon, J., Tholl, D. (2012) The major volatile organic compound emitted from Arabidopsis thaliana flowers, the sesquiterpene (E)-b-caryophyllene, is a defense against a bacterial pathogen. New Phytol. 193, 997–1008PubMedCrossRefGoogle Scholar
  21. Jensen, G.B., Hansen, B.M., Eilenberg, J., Mahillon, J. (2003) The hidden lifestyles of Bacillus cereus and relatives. Environ. Microbiol. 5, 631–640PubMedCrossRefGoogle Scholar
  22. Johnson, K.B., Stockwell, V.O., Mclaughlin, R.J., Sugar, D., Loper, J.E., Roberts, R.G. (1993) Effect of Antagonistic Bacteria on Establishment of Honey Bee-Dispersed Erwinia-Amylovora in Pear Blossoms and on Fire Blight Control. Phytopathology 83, 995–1002CrossRefGoogle Scholar
  23. Junker, R.R., Tholl, D. (2013) Volatile organic compound mediated interactions at the plant-microbe interface. J. Chem. Ecol. 39, 810–825PubMedCrossRefGoogle Scholar
  24. Junker, R.R., Loewel, C., Gross, R., Dötterl, S., Keller, A., Blüthgen, N. (2011) Composition of epiphytic bacterial communities differs on petals and leaves. Plant Biol. 13, 918–924PubMedCrossRefGoogle Scholar
  25. Kai, M., Haustein, M., Molina, F., Petri, A., Scholz, B., Piechulla, B. (2009) Bacterial volatiles and their action potential. Appl. Microbiol. Biotechnol. 81, 1001–1012PubMedCrossRefGoogle Scholar
  26. Knuth, P. (1908) Handbook of flower pollination. Clarendon, OxfordGoogle Scholar
  27. Krimm, U., Abanda-Nkpwatt, D., Schwab, W., Schreiber, L. (2005) Epiphytic microorganisms on strawberry plants (Fragaria ananassa cv. Elsanta): identification of bacterial isolates and analysis of their interaction with leaf surfaces. FEMS Microbiol. Ecol. 53, 483–492PubMedCrossRefGoogle Scholar
  28. Lachance, M.A., Starmer, W.T., Rosa, C.A., Bowles, J.M., Barker, J.S.F., Janzen, D.H. (2001) Biogeography of the yeasts of ephemeral flowers and their insects. Fems Yeast Res. 1, 1–8PubMedCrossRefGoogle Scholar
  29. Leroy P. D., Sabri A., Heuskin S., Thonart P., Lognay G., Verheggen F. J., Francis F., Brostaux Y., Felton G. W., Haubruge E. (2011) Microorganisms from aphid honeydew attract and enhance the efficacy of natural enemies. Nat Commun 2, doi: 10.1038/ncomms1347
  30. Lindow, S.E., Brandl, M.T. (2003) Microbiology of the phyllosphere. Appl. Environ. Microb. 69, 1875–1883CrossRefGoogle Scholar
  31. Lunau, K., Unseld, K., Wolter, F. (2009) Visual detection of diminutive floral guides in the bumblebee Bombus terrestris and in the honeybee Apis mellifera. J. Comp. Physiol. A Neuroethol. Sens. Neural. Behav. Physiol. 195, 1121–1130PubMedCrossRefGoogle Scholar
  32. Maccagnani, B., Giacomello, F., Fanti, M., Gobbin, D., Maini, S., Angeli, G. (2009) Apis mellifera and Osmia cornuta as carriers for the secondary spread of Bacillus subtilis on apple flowers. Biocontrol 54, 123–133CrossRefGoogle Scholar
  33. Mattila, H.R., Rios, D., Walker-Sperling, V.E., Roeselers, G., Newton, I.L.G. (2012) Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse. Plos One 7 Google Scholar
  34. Ondov B. D., Bergman N. H., Phillippy A. M. (2011) Interactive metagenomic visualization in a Web browser. Bmc Bioinforma. 12, doi: 10.1186/1471-2105-1112-1385
  35. Ponnusamy, L., Xu, N., Nojima, S., Wesson, D.M., Schal, C., Apperson, C.S. (2008) Identification of bacteria and bacteria-associated chemical cues that mediate oviposition site preferences by Aedes aegypti. Proc. Natl. Acad. Sci. U. S. A. 105, 9262–9267PubMedCentralPubMedCrossRefGoogle Scholar
  36. Pozo, M.I., Lachance, M.A., Herrera, C.M. (2012) Nectar yeasts of two southern Spanish plants: the roles of immigration and physiological traits in community assembly. FEMS Microbiol. Ecol. 80, 281–293PubMedCrossRefGoogle Scholar
  37. R Development Core Team (2011) R: A language and environment for statistical computing. ed.^eds.), p.^pp. R Foundation for Statistical Computing, Vienna.Google Scholar
  38. Sanchez, M.G.D. (2011) Taste Perception in Honey Bees. Chem. Senses 36, 675–692CrossRefGoogle Scholar
  39. Schulz, S., Dickschat, J. (2007) Bacterial volatiles: the smell of small organisms. Nat. Prod. Rep. 24, 814–842PubMedCrossRefGoogle Scholar
  40. Shade, A., McManus, P.S., Handelsman, J. (2013) Unexpected diversity during community succession in the apple flower microbiome. mBio 4, e00602–e00612PubMedCentralPubMedCrossRefGoogle Scholar
  41. Stensmyr, M.C., Dweck, H.K.M., Farhan, A., Ibba, I., Strutz, A., Mukunda, L., Linz, J., Grabe, V., Steck, K., Lavista-Llanos, S., Wicher, D., Sachse, S., Knaden, M., Becher, P.G., Seki, Y., Hansson, B.S. (2012) A conserved dedicated olfactory circuit for detecting harmful microbes in Drosophila. Cell 151, 1345–1357PubMedCrossRefGoogle Scholar
  42. van der Steen, J.J.M., Langerak, C.J., van Tongeren, C.A.M., Dik, A.J. (2004) Aspects of the use of honeybees and bumblebees as vector of antagonistic micro-organisms in plant disease control. Proc. Neth. Entomol. Soc. 15, 41–46Google Scholar
  43. Vannette, R.L., Gauthier, M.-P.L., Fukami, T. (2012) Nectar bacteria, but not yeast, weaken a plant–pollinator mutualism. Proc. R. Soc. B 280, 20122601PubMedCrossRefGoogle Scholar
  44. Wang, Q., Garrity, G.M., Tiedje, J.M., Cole, J.R. (2007) Naive Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy. Appl. Environ. Microbiol. 73, 5261–5267PubMedCentralPubMedCrossRefGoogle Scholar
  45. Yang, C.-H., Crowley, D.E., Borneman, J., Keen, N.T. (2001) Microbial phyllosphere populations are more complex than previously realized. Proc. Natl. Acad. Sci. U. S. A. 98, 3889–3894PubMedCentralPubMedCrossRefGoogle Scholar

Copyright information

© INRA, DIB and Springer-Verlag France 2014

Authors and Affiliations

  • Robert R. Junker
    • 1
    • 2
    Email author
  • Tanja Romeike
    • 1
  • Alexander Keller
    • 3
  • Daniela Langen
    • 1
  1. 1.Institute of Sensory Ecology, Department BiologyHeinrich-Heine University DüsseldorfDüsseldorfGermany
  2. 2.Present Address: Department of Organismic BiologyUniversity SalzburgSalzburgAustria
  3. 3.DNA Analytics Core Facility, Department of Animal Ecology and Tropical BiologyUniversity WürzburgWürzburgGermany

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