Oecologia

, Volume 173, Issue 3, pp 985–996

The diversity and fitness effects of infection with facultative endosymbionts in the grain aphid, Sitobion avenae

  • Piotr Łukasik
  • Maciej A. Dawid
  • Julia Ferrari
  • H. Charles J. Godfray
Community ecology - Original research

DOI: 10.1007/s00442-013-2660-5

Cite this article as:
Łukasik, P., Dawid, M.A., Ferrari, J. et al. Oecologia (2013) 173: 985. doi:10.1007/s00442-013-2660-5

Abstract

Mutualisms with facultative, non-essential heritable microorganisms influence the biology of many insects, and they can have major effects on insect host fitness in certain situations. One of the best-known examples is found in aphids where the facultative endosymbiotic bacterium Hamiltonella defensa confers protection against hymenopterous parasitoids. This symbiont is widely distributed in aphids and related insects, yet its defensive properties have only been tested in two aphid species. In a wild population of the grain aphid, Sitobion avenae, we identified several distinct strains of endosymbiotic bacteria, including Hamiltonella. The symbiont had no consistent effect on grain aphid fecundity, though we did find a significant interaction between aphid genotype by symbiont status. In contrast to findings in other aphid species, Hamiltonella did not reduce aphid susceptibility to two species of parasitoids (Aphidius ervi and Ephedrus plagiator), nor did it affect the fitness of wasps that successfully completed development. Despite this, experienced females of both parasitoid species preferentially oviposited into uninfected hosts when given a choice between genetically identical individuals with or without Hamiltonella. Thus, although Hamiltonella does not always increase resistance to parasitism, it may reduce the risk of parasitism in its aphid hosts by making them less attractive to searching parasitoids.

Keywords

Acyrthosiphon pisumSecondary endosymbiontAPSERegiella insecticolaSerratia symbiotica

Supplementary material

442_2013_2660_MOESM1_ESM.doc (540 kb)
Supplementary material (DOC 540 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Piotr Łukasik
    • 1
    • 3
  • Maciej A. Dawid
    • 1
  • Julia Ferrari
    • 1
    • 2
  • H. Charles J. Godfray
    • 1
  1. 1.Department of ZoologyUniversity of OxfordOxfordUK
  2. 2.Department of BiologyUniversity of YorkYorkUK
  3. 3.Department of BiologyDrexel UniversityPhiladelphiaUSA