Rosy Apple Aphid (Whalon lab)
Rosy Apple Aphid (Whalon lab, MSU)

While nothing can match the pure undiluted awesomeness that is the parasitoid wasp/bracovirus symbiosis,1 there are other symbioses that are at least in the same ballpark.  The latest one I’ve learned about is the relationship between a densovirus and the rosy apple aphid. 2  I can’t do better than to quote the abstract:

Winged morphs of aphids are essential for their dispersal and survival. We discovered that the production of the winged morph in asexual clones of the rosy apple aphid, Dysaphis plantaginea, is dependent on their infection with a DNA virus, Dysaphis plantaginea densovirus (DplDNV). Virus-free clones of the rosy apple aphid, or clones infected singly with an RNA virus, rosy apple aphid virus (RAAV), did not produce the winged morph in response to crowding and poor plant quality. DplDNV infection results in a significant reduction in aphid reproduction rate, but such aphids can produce the winged morph, even at low insect density, which can fly and colonize neighboring plants. Aphids infected with DplDNV produce a proportion of virus-free aphids, which enables production of virus-free clonal lines after colonization of a new plant.2

So without the virus, the aphids don’t grow wings, and they’re not able to disperse to new sites. When infected, they can sprout wings, and spread to a new site. Presumably without a flying aphid to carry them the virus can’t disperse, either.

Apart from anything else, my kids, having learned about this at dinner,3 are now hoping to have their wings turned on the next time they’re infected with a virus.


  1. Bioweaponized wasps shooting mutualistic immune suppressive viruses at their prey! Pew! Pew! Pew! []
  2. Ryabov, E., Keane, G., Naish, N., Evered, C., & Winstanley, D. (2009). Densovirus induces winged morphs in asexual clones of the rosy apple aphid, Dysaphis plantaginea Proceedings of the National Academy of Sciences, 106 (21), 8465-8470 DOI: 10.1073/pnas.0901389106[][]
  3. We have interesting dinner conversations at my house[]