Aleochara bipustulata
The microbiote of the root maggot and of its natural enemies

The microbiote of the root maggot and of its natural enemies: rich, but not shared

The root maggot Delia radicum is a major pest of cole crops and its main natural enemies are the predator and parasitoid rove beetles Aleochara bilineata, Aleochara bipustulata and the parasitoid wasp Trybliographa rapae.

To prepare the study of the impact of micro-organisms harbored by the interacting species of this trophic network we have sequenced the microbiotes of the four species involved, using 4-5-4 technology on pools of 20 individuals and two populations per species. The bacterial communities revealed are rich (approx. 100-200 OTU per host species) but only marginally shared: in particular, no OTU is found in all four species. Host phylogeny – and not trophic interactions – is thus the main driver structuring the microbiote here. Each microbiote is strongly dominated by one or two taxa. Finally, at least three genus of vertically transmitted symbionts have been found in this trophic network (Wolbachia, Rickettsia and Spiroplasma). The root maggot and the two rove beetles all harbor Wolbachia, but their bacterial variants are different, which excludes a recent horizontal transfer.

We will now study how the microbiote of the root maggot is established during its development, and the impact of this bacterial community on its host.

Bili M., Cortesero A.M., Mougel C., Gauthier J.P., Ermel G., Simon J.C., Outreman Y., Terrat S., Mahéo F. & Poinsot D. (2016). Bacterial Community Diversity Harboured by Interacting Species. PLoS ONE, 11(6): e0155392. pdf