Effect of the gut microbiota on insect reproduction: mechanisms and biotechnological prospects

The insect gut microbiota functions as a multifunctional symbiotic system that plays a central role in host reproduction. Through the production of bioactive metabolites, gut microbes interact with host hormonal pathways, immune signaling, and molecular regulatory networks, thereby shaping reproductive physiology and fitness. This review summarizes recent advances in understanding how gut microbiota regulate insect reproduction. Accumulating evidence demonstrates that microbial metabolites contribute to nutrient metabolism and the provision of essential cofactors, modulate hormone signaling pathways involved in reproductive development, and participate in pheromone biosynthesis that affects mating behavior. These processes impact both female and male reproductive functions through coordinated interactions among metabolism, endocrine regulation, and chemical communication. In females, microbial metabolites such as short-chain fatty acids and vitamins regulate insulin/TOR and juvenile hormone signaling, promoting ovarian development, vitellogenin synthesis, and oviposition. In males, gut bacteria influence spermatogenesis, sperm motility, and pheromone production, which are critical for mating success and fertility. Overall, these findings provide a mechanistic foundation for applied strategies, including Wolbachia-based population suppression, probiotic supplementation to enhance sterile insect technique (SIT) performance, and microbial manipulation of pheromone production for pest control. In addition, dietary conditions and environmental stressors can reshape gut microbial composition and metabolic activity, leading to changes in reproductive outcomes. Furthermore, this review emphasizes the complex interactions between insect gut microbiota and reproductive physiology. Key insights include: (i) the role of microbial metabolites in regulating mating behavior, oviposition, and offspring development; (ii) the potential of microbiota-based strategies for pest control, such as Wolbachia-mediated population suppression and probiotic enhancement of SIT; and (iii) the impact of external factors, including diet and environmental conditions, on reproduction through microbiota-mediated pathways. These findings deepen our understanding of insect-microbe symbiosis and its implications for evolutionary biology and sustainable pest management. © 2026 Society of Chemical Industry.