Parasitoids as vectors of facultative bacterial endosymbionts in aphids.
ABSTRACT Heritable bacterial endosymbionts play an important role in aphid ecology. Sequence-based evidence suggests that facultative symbionts such as Hamiltonella defensa or Regiella insecticola also undergo horizontal transmission. Other than through male-to-female transfer during the sexual generation in autumn, the routes by which this occurs remain largely unknown. Here, we tested if parasitoids or ectoparasitic mites can act as vectors for horizontal transfer of facultative symbionts. Using symbiont-specific primers for diagnostic PCR, we demonstrate for the first time, to our knowledge, that parasitoids can indeed transfer H. defensa and R. insecticola by sequentially stabbing infected and uninfected individuals of their host, Aphis fabae, establishing new, heritable infections. Thus, a natural route of horizontal symbiont transmission is also available during the many clonal generations of the aphid life cycle. No transmissions by ectoparasitic mites were observed, nor did parasitoids that emerged from symbiont-infected aphids transfer any symbionts in our experiments.
Article: Arthropods and inherited bacteria: from counting the symbionts to understanding how symbionts count.BMC Biology 01/2013; 11:45. · 5.75 Impact Factor
Article: Correction: Male-killing Wolbachia and mitochondrial selective sweep in a migratory African insect.[show abstract] [hide abstract]
ABSTRACT: Following publication of our work (Graham and Wilson, BMC Evol Biol, 2012, 12:204), it was brought to our attention that seven of the mitochondrial COI haplotypes described in this manuscript as Spodoptera exempta haplotypes were in fact other species. As a result, we cannot now support one of our original conclusions suggesting that the Spodoptera genus was not monophyletic. However, it should be clearly stated that the main findings of the article, namely that the presence of three Wolbachia species appear to be driving a mitochondrial selective sweep within S. exempta, still holds true. Indeed, the new analysis strengthens the extent of the host mitochondrial skew (94.3% prevalence of haplo1).BMC Evolutionary Biology 01/2013; 13(1):6. · 3.52 Impact Factor