Bactrocera dorsalis and Its Gut Microbiota: An Emerging Insect Model

The gut microbiota influences host health, development, nutrition, and behavior, positioning it as a frontier research area in life sciences. Bactrocera dorsalis is a major agricultural pest, with a short life cycle, ease of laboratory rearing, and the availability of germ-free larvae. The gut microbiota of B. dorsalis is complex and relatively insensitive to environmental influences. Due to these advantages, B. dorsalis has emerged as a promising model organism for gut microbiota research. This review synthesizes the advantages of B. dorsalis as a model organism, detailing its gut structure and the composition of its microbiota across developmental stages, sexes, diets, and geographical populations—highlighting the dominance of Enterobacteriaceae as a core component. Key functional roles of gut microbiota in B. dorsalis are elucidated, including nutrient provisioning, regulation of development and reproduction, enhancement of environmental adaptability, behavioral modulation, pesticide resistance, and immune interactions. The mechanisms underpinning gut microbiota homeostasis, involving the host Duox/ROS system, NOX enzymes, and the Imd pathway, are also discussed. Limitations are addressed, alongside future directions for leveraging genetic tools to dissect host–microbe interplay. Furthermore, the potential applications of gut microbiota research—including probiotics for Sterile Insect Technique optimization, microbial-based attractants, and paratransgenesis for pest control—are emphasized. Collectively, B. dorsalis offers a platform for understanding intricate host–microbe interplay and inspires novel pest management strategies.