First Glimpse of Gut Microbiota of Quarantine Insects in China

Quarantine insects are economically important pests that frequently invade new habitats. A rapid and accurate monitoring method to trace the geographical source of invaders is therefore needed for prevention, detection, and eradication. Current methods based on insect genetics are often too slow. We developed a novel tracing method based on insect gut microbiota. The source location of microbiota of insects can be used to rapidly determine the insects geographic origin. We analyzed 179 gut microbiota samples belonging to 591 individuals of 22 quarantine insect species collected from 36 regions in China and abroad. The gut microbiotas of these insects mainly included Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, Proteobacteria, and Tenericutes. The diversity of the insect gut microbiota was closely related to geographic and environmental factors. Different insect species could be distinguished at the phylum level of microbiota. Populations of individual insect species from different regions could be distinguished at the genus level of microbiota. A method for determining the geographical origin of invasive insect species was tentatively established, but its practical applicability requires further study.