Strain Gri From the Tea Geometrid Moth Contributes to Its Host's Fecundity.

Members of the genus manipulate insect-host reproduction and are the most abundant bacterial endosymbionts of insects. The tea Geometrid moth (Warren) (Lepidoptera: Geometridae) is the most devastating insect pest of tea plants [ (L.) O. Kuntze] in China. However, limited data on the diversity, typing, or phenotypes of in are available. Here, we used a culture-independent method to compare the gut bacteria of and other tea Geometridae moths. The results showed that the composition of core gut bacteria in larvae of the three Geometridae moth species was similar, except for the presence of . Moreover, was also present in adult female samples. A strain was isolated from and designated as Gri. Comparative analyses showed that this strain shared multilocus sequence types and surface protein hypervariable region profiles with cytoplasmic incompatibility (CI)-inducing strains in supergroup B; however, the Gri-associated phenotypes were undetermined. A reciprocal cross analysis showed that -uninfected females mated with infected males resulted in 100% embryo mortality (0% eggs hatched per female). Eggs produced by mating between uninfected males and infected females hatched normally. These findings indicated that Gri induces strong unidirectional CI in . Additionally, compared with uninfected females, -infected females produced approximately 30-40% more eggs. Together, these results show that this strain induces reproductive CI in and enhances the fecundity of its female host. We also demonstrated that Gri potential influences reproductive communication between and through CI.