Gut bacterial communities of Lymantria xylina and their associations with host development and diets

The gut microbiota of insects have a wide range of effects on host nutrition, physiology, and behavior. The structure of gut microbiota might also be shaped by their environment causing them to adjust to their hosts; thus, the objective of this study was to examine variations in the morphological traits and gut microbiota of Lymantria xylina in response to natural and artificial diets using high-throughput pyrosequencing. Regarding morphology, the head width for larvae fed on a sterilized artificial diet was smaller than for larvae fed on a non-sterilized host-plant diet in the early instars. The gut microbiota diversity of L. xylina fed on different diets was significantly different but did not change during different development periods. This seemed to indicate vertical inheritance occurred in L. xylina mutualistic symbionts. Acinetobacter and Enterococcus were dominant in eggs. In first instar larvae, Acinetobacter accounted for 33.52% for the sterilized artificial diet treatment, while Enterococcus (67.88%) was the predominant bacteria for the non-sterilized host-plant diet treatment. Gut microbe structures were adapted to both diets through vertical inheritance and self-regulation. This study clarified the impacts of microbial symbiosis on L. xylina and may provide new possibilities for improving the control of these bacteria.