The effect of Candidatus Liberibacter infection on the microbiome of Bactericera cockerelli and Diaphorina citri, vectors of zebra chip and Huanglongbing

Candidatus Liberibacter species have recently been implicated as causative agents in both Zebra Chip (ZC) and Huanglongbing (HLB), diseases of potatoes and citrus respectively. ZC and HLB are limiting factors in the production of these crops and intense research of the vectors, the potato psyllid (Bactericera cockerelli) and the Asian citrus psyllid (Diaphorina citri), is ongoing. An insect’s microbiome consists of the microbial flora present in the body and may serve as a possible avenue of biological control. In this study, the microbial flora associated with B. cockerelli and D. citri was evaluated. A comprehensive study of the microbiome of four life stages (egg, early instars, 5th instars and adults) was determined by pyrosequencing of 16S ribosomal DNA using the bTEFAP methodology. The resulting sequences were compared to a curated high quality 16S rDNA database derived from NCBI’s GenBank. Some of the bacteria identified in this report are initial discoveries; species from the genera Wolbachia, Rhizobium, Gordonia, Mycobacterium, Xanthomonas and many others were detected and an assessment of the microbiome associated with B. cockerelli was established for each lifestage. Next, microbial flora associated with adult B. cockerelli and D. citri (both positive and negative for Candidatus Liberibacter sp.) were analyzed and compared.