High prevalence of Wolbachia in the azuki bean beetle Callosobruchus chinensis (Coleoptera, Bruchidae)

Members of the family Bruchidae (Insecta, Coleoptera) were examined for Wolbachia infection. Out of seven species investigated, which represented three subfamilies and five genera, amplified bands were detected only from Callosobruchus chinensis by diagnostic PCR with Wolbachia-specific primers. Bacterial 16S rDNA was amplified by PCR, cloned and sequenced from the total DNA of C. chinensis. Molecular phylogenetic analysis demonstrated that the sequence belongs to a monophyletic group of the genus Wolbachia in the cc-Proteobacteria. The Wolbachia was detected from all tissues and body parts such as ovary, gut, fat body, muscle, wing, leg, head and antenna. In six geographic populations from central Japan, all the individuals examined, more than 400 in total, possessed the Wolbachia, indicating high prevalence of Wolbachia among natural populations of C. chinensis.