Journal article
Intraspecific variation in symbiont density in an insect-microbe symbiosis
- Abstract:
- Many insects host vertically transmitted microbes, which can confer benefits to their hosts but are costly to maintain and regulate. A key feature of these symbioses is variation: for example, symbiont density can vary among host and symbiont genotypes. However, the evolutionary forces maintaining this variation remain unclear. We studied variation in symbiont density using the pea aphid (Acyrthosiphon pisum) and the bacterium Regiella insecticola, a symbiont that can protect its host against fungal pathogens. We found that relative symbiont density varies both between two Regiella phylogenetic clades and among aphid “biotypes.” Higher density symbiont infections are correlated with stronger survival costs, but variation in density has little effect on the protection Regiella provides against fungi. Instead, we found that in some aphid genotypes, a dramatic decline in symbiont density precedes the loss of a symbiont infection. Together, our data suggest that the optimal density of a symbiont infection is likely different from the perspective of aphid and microbial fitness. Regiella might prevent loss by maintaining high within‐host densities, but hosts do not appear to benefit from higher symbiont numbers and may be advantaged by losing costly symbionts in certain environments. The standing variation in symbiont density observed in natural populations could therefore be maintained by antagonistic coevolutionary interactions between hosts and their symbiotic microbes.
- Publication status:
- Published
- Peer review status:
- Peer reviewed
Actions
Access Document
- Files:
-
-
(Preview, Accepted manuscript, 801.0KB, Terms of use)
-
- Publisher copy:
- 10.1111/mec.15821
Authors
- Publisher:
- Wiley
- Journal:
- Molecular Ecology More from this journal
- Volume:
- 30
- Issue:
- 6
- Pages:
- 1559-1569
- Publication date:
- 2021-02-11
- Acceptance date:
- 2021-01-20
- DOI:
- EISSN:
-
1365-294X
- ISSN:
-
0962-1083
- Pmid:
-
33512733
- Language:
-
English
- Keywords:
- Pubs id:
-
1159363
- Local pid:
-
pubs:1159363
- Deposit date:
-
2021-02-22
Terms of use
- Copyright holder:
- John Wiley & Sons Ltd
- Copyright date:
- 2021
- Rights statement:
- © 2021 John Wiley & Sons Ltd
- Notes:
-
This is the accepted manuscript version of the article. The final version is available from Wiley at https://doi.org/10.1111/mec.15821
If you are the owner of this record, you can report an update to it here: Report update to this record