Abstract:  Wolbachia is a group of intracellular symbionts ubiquitous in arthropods. To investigate the Wolbachia infection in Chinese aphids, we amplified the wsp gene of Wolbachia in different geographical populations of three wheat aphids (Sitobion miscanthi, Schizaphis graminum and Rhopalosiphum padi) and one soybean aphid (Aphis glycines) in this study. The results showed that Wolbachia was not detected in the three wheat aphids. In A. glycines, Wolbachia was only detected in two geographical populations of Beijing and Hangzhou, with the infection rates of 95.8% and 22.9%, respectively. Moreover, the sequenced samples were infected with single Wolbachia strain. The Blastn search results showed that wsp gene sequences are similar among Wolbachia strains isolated from A. glycines and from some distantly related host insect species. The wsp gene phylogeny revealed that Wolbachia strains isolated from A. glycines belong to Wolbachia B supergroup, CauB group. This study provides the data for further investigation on host range and strain diversity of Wolbachia in Chinese aphid species.

Key words:  Sitobion miscanthi, Schizaphis graminum, Rhopalosiphum padi; Aphis glycines, Wolbachia, mitochondrial gene, wsp gene, phylogenetic analysis