Differences in bacterial communities associated with cotton fleahopper on two host plants across Texas

Background/Question/Methods

Herbivorous insects are known to harbor microbial symbionts that provide several ecological advantages. For example, bacterial symbionts in some insects allow them to use otherwise inadequate plants. Such mutualistic associations can lead to the formation of genetically divergent host-associated insect populations. Previous studies have indicated the presence of host associated genetic differentiation (HAD) in the cotton fleahopper (CFH), Pseudatomoscelis seriatus, associated with two host plants: Cotton and horsemint. In this study, we investigate the role of  microbial diversity in HAD. To this end we performed a barcoded 454 pyrosequencing on pooled samples of CFH from the two host plants across Texas. We used pyrosequencing statistical analyses to characterize bacterial communities of CFH.

Results/Conclusions

The bacterial diversity associated with CFH differed on cotton and horsemint. The facultative bacteria, Wolbachia, which is thought to be widespread in most insects was absent in all populations except one population in Texas. Further phylogenetic analysis of Wolbachia sequences indicated the presence of two strains of Wolbachia occurring between cotton-associated and horsemint-associated CFH populations. This study indicates that symbiotic associations of insects might play important role when investigating genetic structure in herbivorous populations.