Advances in research on the chemical ecology of interactions between invasive pests and microbes
Author of the article:SONG Jia-Le1, 2** XU Yi-Juan1*** TANG Rui2***
Author's Workplace：1. College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; 2. Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China
Key Words：invasive insect pests; microbial interactions; chemical ecology; volatile organic compounds; pheromones; green pest management
Abstract：Invasive insect pests have become a major threat to global agricultural production, ecological security and biodiversity. Their rapid establishment, expansion, and outbreaks are closely associated, not only with their remarkable environmental adaptability, but also with their complex interactions with symbiotic microorganisms and sophisticated chemical communication networks. In recent years, advances in chemical ecology, microbiome research and multi-omics technologies have highlighted the pivotal roles of microorganisms in facilitating the adaptation of invasive insects to novel environments, the regulation of host behavior and the mediation of multitrophic interactions. This review systematically summarizes recent advances in microorganism-mediated chemical signal production, chemical signal perception and interaction mechanisms, as well as microorganism-based, environmentally-friendly pest management strategies. We first summarize the functions of obligate symbionts, facultative symbionts, gut microbiota, entomopathogenic microorganisms and environmental microorganisms in host nutrition, immune regulation, reproductive manipulation, insecticide resistance and ecological adaptation. We then discuss the molecular mechanisms by which microorganisms participate in the biosynthesis of insect pheromones and volatile organic compounds (VOCs), regulate plant volatile emissions and mediate chemical communication within plant-insect-microorganism multitrophic interactions, highlighting that microorganisms are not only important sources of chemical signals, but also key drivers of insect behavior and ecological interactions. Furthermore, this review outlines emerging microorganism-based, environmentally-friendly control strategies, including push-pull systems based on microbial volatile compounds, symbiont-mediated population regulation, the integration of Wolbachia-based approaches with the Sterile Insect Technique and CRISPR gene editing, and the synergistic application of entomopathogenic microorganisms with semiochemicals. Their underlying mechanisms and potential for application are also discussed. Current evidence suggests that microorganisms facilitate the adaptation of invasive insect pests to host plants and novel environments by reshaping chemical communication networks, thereby serving as critical links connecting plants, herbivores, and natural enemies across multitrophic systems. These findings provide an important theoretical foundation for developing next-generation green pest management strategies. Future research should focus on elucidating the biosynthetic mechanisms of bioactive microbial volatiles, promoting the integration of multi-omics approaches with chemical ecology, establishing artificial intelligence- assisted high-throughput, screening platforms for bioactive volatile compounds, and integrating gene editing, symbiont engineering and synthetic biology with the utilization of microbial resources. In addition, greater emphasis should be placed on field validation and ecological risk assessment to facilitate the development of innovative, environmentally-friendly management technologies for invasive insect pests, and promote sustainable agricultural development.