Molecular characterization and ecological survey of Wolbachia in Florida Diaphorina citri (Hemiptera: Liviidae) populations

Due to their ability to influence host reproduction, endosymbiotic bacteria of the genus Wolbachia have been studied extensively across a broad range of species. Manipulation of Wolbachia spp. in some insect vectors has shown potential for mediating pathogen transmission. The Asian citrus psyllid, Diaphorina citri Kuwayama, is a vector of Ca. Liberibacter asiaticus, the causal agent of citrus greening (huanglongbing, HLB). Although Wolbachia occur naturally in D. citri, little is known about the factors that regulate Wolbachia density in insect hosts. In the present study, we assessed the within-host densities of Florida D. citri populations and characterized Wolbachia sequence types via multi locus sequence typing (MLST). Analysis of Wolbachia gene loci indicated the predominance of one sequence type among all Florida D. citri populations. Differences in the with-in host density of the primary Wolbachia sequence type were observed in field populations. Laboratory assays suggest that within-host Wolbachia density was affected by temperature, sex and host age.