Effects of Antibiotic Treatment on the Development and Bacterial Community of the Wolbachia-Infected Diamondback Moth

Based on the important role of antibiotic treatment in the research of the interaction between Wolbachia and insect hosts, this study aimed to identify the most suitable antibiotic and concentration for Wolbachia elimination in the P. xylostella, and to investigate the effect of Wolbachia and antibiotic treatment on the bacterial community of P. xylostella. Our results showed that the Wolbachia-infected strain was plutWB1 of supergroup B in the P. xylostella population collected in Nepal in this study; 1 mg/mL rifampicin could remove Wolbachia infection in P. xylostella after 1 generation of feeding treatment and the toxic effect was relatively low; among the 29 samples of adult P. xylostella in our study (10 WU samples, 10 WA samples, and 9 WI samples), 52.5% of the sequences were of Firmicutes and 47.5% were of Proteobacteria, with the dominant genera being mainly Carnobacterium (46.2%), Enterobacter (10.1%), and Enterococcus (6.2%); Moreover, antibiotic removal of Wolbachia infection in P. xylostella and transfer to normal conditions for 10 generations no longer significantly affected the bacterial community of P. xylostella. This study provides a theoretical basis for the elimination method of Wolbachia in the P. xylostella, as well as a reference for the elimination method of Wolbachia in other Wolbachia-infected insect species, and a basis for the study of the extent and duration of the effect of antibiotic treatment on the bacterial community of the P. xylostella.