Comparative microbiome analysis reveals bacterial communities associated with Candidatus Liberibacter asiaticus infection in the Huanglongbing insect vector Diaphorina citri

Abstract

• Candidatus Profftella, Wolbachia , and Candidatus Carsonella were the most abundant genera in all samples. • C Las-infected samples harboured more OTUs and showed higher alpha diversity metric. • Candidatus Profftella was more abundant in the non-infected group. • The relationship between Candidatus Profftella and C Las was co-exclusion. • The relationship among C Las, Wolbachia and multiple other bacteria were co-existed. The Asian citrus psyllid ( Diaphorina citri ) is a major pest of the citrus industry and is also the vector for Candidatus Liberibacter asiaticus ( C Las), a destructive Huanglongbing (HLB) disease of citrus trees. Insect endosymbionts and gut bacteria play important roles in vector-pathogen interactions and host immunity. Thus, our aim was to evaluate the correlation between C Las infection and the microbiome in D. citri by conducting 16S rRNA amplification sequencing on insects successfully and unsuccessfully infected with C Las ( C Las-infected and non-infected). Genera Candidatus Profftella, Wolbachia , and Candidatus Carsonella were highly abundant genera in all tested samples. Compared with the non-infected and control groups, C Las-infected samples harboured more observed OTUs and showed higher alpha diversity metrics. Principal coordinate analysis based on beta-diversity metrics indicated two distinct clusters between the C Las-infected samples and non-infected/control samples. Subsequent LEfSe analysis revealed that Candidatus Profftella was more abundant in the non-infected group than in the control and C Las-infected groups. The interaction network also indicated a co-exclusion relationship between Candidatus Profftella and C Las, while C Las co-existed with Wolbachia , several Enterobacteriaceae spp . , and multiple other bacteria. Our study provides insight into the interaction between the microbiome community in D. citri and C Las, which can facilitate the management of this pest and its associated pathogen.