Analysis of the bacterial communities of four predatory natural enemies collected from a Northern China Bt cotton field

Predatory natural enemies are major insect species in cotton field ecosystems. Microbes that live inside these insects play essential roles in vital host activities, however, the microbiota of these insects have not been well characterized. In this study, we used Illumina 16S rRNA amplicon sequencing to investigate microbial diversity of the natural enemies Chrysoperla sinica, Harmonia axyridis, Propylaea japonica and Orius similis from a cotton field in northern China. The microbial diversity of C. sinica was low and its dominant bacterial community were Rickettsia (87.78%) and Wolbachia (6.29%). The microbial community of O. similis was more diverse than that of C. sinica. The microbial diversity of H. axyridis and P. japonica was higher, and they had similar dominant phyla, which included Firmicutes, Proteobacteria and Bacteroidetes. Their common dominant bacterial community were Romboutsia, Escherichia-Shigella, Bacteroides, Terrisporobacter, Enterobacter, Lactobacillus, Fusobacterium, Actinobacillus, Sphaerochaeta, Bacteroidales_S24-7_group and Cyanobacteria. This study also forms the basis for further study on the microbiota of natural enemies from different habitats.