Horizontal transfers of feminizing versus non‐feminizing W olbachia strains: from harmless passengers to pathogens

Abstract

Summary The endosymbiont W olbachia pipientis infects various hosts in which it navigates vertically from mothers to offspring. However, horizontal transfers of W olbachia can occur between hosts. The virulence of the horizontally acquired W olbachia can change in the new host as it has been illustrated by the case of the feminizing strain w V ul C from the woodlouse A rmadillidium vulgare that turns to a pathogen when introduced into P orcellio dilatatus dilatatus. In the present study, we aim to show whether symbiotic traits, such as (i) host sex manipulation and (ii) colonization patterns, which differ between eight isopod W olbachia strains, are connected to their virulence towards the recipient host P . d. dilatatus . Among the transferred W olbachia , some feminizing strains gradually differing in feminizing intensity in their native hosts induced different levels of pathogenicity to P . d. dilatatus . Not a single feminizing strain passed vertically with high titres to the next generation. The non‐feminizing W olbachia strains, even if they reached high densities in the host, did not impact host life‐history traits and some vertically passed with high titres to the offspring. These results suggest that a potential link between the manners W olbachia manipulates its native host reproduction, its virulence and its ability to vertically infect the offspring.

Bibliographic Information