Effects of bacterial secondary symbionts on host plant use in pea aphids. (2011)

First Author: McLean AH

Attributed to:  Aphid secondary symbionts: a eukaryote horizontal gene pool funded by NERC


Aphids possess several facultative bacterial symbionts that have important effects on their hosts' biology. These have been most closely studied in the pea aphid (Acyrthosiphon pisum), a species that feeds on multiple host plants. Whether secondary symbionts influence host plant utilization is unclear. We report the fitness consequences of introducing different strains of the symbiont Hamiltonella defensa into three aphid clones collected on Lathyrus pratensis that naturally lack symbionts, and of removing symbionts from 20 natural aphid-bacterial associations. Infection decreased fitness on Lathyrus but not on Vicia faba, a plant on which most pea aphids readily feed. This may explain the unusually low prevalence of symbionts in aphids collected on Lathyrus. There was no effect of presence of symbiont on performance of the aphids on the host plants of the clones from which the H. defensa strains were isolated. Removing the symbiont from natural aphid-bacterial associations led to an average approximate 20 per cent reduction in fecundity, both on the natural host plant and on V. faba, suggesting general rather than plant-species-specific effects of the symbiont. Throughout, we find significant genetic variation among aphid clones. The results provide no evidence that secondary symbionts have a major direct role in facilitating aphid utilization of particular host plant species.

Bibliographic Information

Digital Object Identifier: http://dx.doi.org/10.1098/rspb.2010.1654

PubMed Identifier: 20843842

Publication URI: http://europepmc.org/abstract/MED/20843842

Type: Journal Article/Review

Volume: 278

Parent Publication: Proceedings. Biological sciences

Issue: 1706

ISSN: 0962-8452