Gut Bacterial Community Structure and Function Prediction of Lygus pratensis at Different Developmental Stages

L. pratensis is a significant pest of cotton. Clarifying the intestinal bacterial structure of L. pratensis can provide a theoretical basis for the development of new pest biological control strategies. In this study, high-throughput sequencing was employed to characterize the intestinal bacterial communities across five L. pratensis populations, and the functions of their core metabolic pathways were predicted. The results showed that the intestinal bacterial communities of the five L. pratensis populations comprised 16 phyla, 25 classes, 54 orders, 85 families, 133 genera, and 187 species. Diversity analysis revealed that the diversity of the intestinal bacterial community exhibited a dynamic trend of first increasing and then decreasing during the pest's growth and development. Specifically, the Shannon and Simpson diversity indices of the nymphal stage were significantly higher than those of the egg and adult stages (p < 0.05). The dominant phylum, class, order, family, genus and species shared by the five groups were Proteobacteria (93.17%), Gammaproteobacteria (48.71%), Rickettsiales (43.83%), Anaplasmataceae (49.39%), Wolbachia (43.83%) and Wolbachia (43.82%). Among them, Acinetobacter was mainly found in the first instar nymph stage, and Serratia was mainly distributed in the fifth instar nymph and female and male adults. Functional prediction results showed that the intestinal bacterial community was mainly enriched in core pathways, including metabolism, genetic information processing, and environmental information processing. This study provides a new target for green prevention and control of L. pratensis and also provides a theoretical basis for further elucidating the succession law and functional mechanism of its gut microbiota.