The pivotal roles of gut microbiota in insect plant interactions for sustainable pest management

Abstract

The gut microbiota serves as a critical "organ" in the life cycle of animals, particularly in the intricate interplay between herbivorous pests and plants. This review summarizes the pivotal functions of the gut microbiota in mediating the insect-plant interactions, encompassing their influence on host insects, modulation of plant physiology, and regulation of the third trophic level species within the ecological network. Given these significant functions, it is plausible to harness these interactions and their underlying mechanisms to develop novel eco-friendly pest control strategies. In this context, we also outline some emerging pest control methods based on the intestinal microbiota or bacteria-mediated interactions, such as symbiont-mediated RNAi and paratransgenesis, albeit these are still in their nascent stages and confront numerous challenges. Overall, both opportunities and challenges coexist in the exploration of the intestinal microbiota-mediated interactions between insect pests and plants, which will not only enrich the fundamental knowledge of plant-insect interactions but also facilitate the development of sustainable pest control strategies.

Fig. 1. Known functions of insect gut bacteria that directly influence insect behavior and physiology.

a Gut bacteria mediate insects’ plant selection preference; b Gut bacteria assist insects in overcoming feeding obstacles; c Plant defense-induced dysbiosis of gut microbiota is lethal to insects.

Fig. 2. Gut bacteria participate in plant–insect interactions.

The purple circle represents an example of gut bacteria promoting plant growth directly. The yellow one represents an example of gut bacteria regulating SA/JA signaling pathways of plants. And the brown circle shows an example of gut bacteria inducing the production of plant VOCs to attract/repel natural enemies of insects.

Fig. 3. Gut bacteria participate in plant–insect interactions by exerting an influence on the third trophic-level species.

a Some gut bacteria show synergistic effects with entomopathogens to kill insects; b gut bacteria in several insects possess antagonistic effects against pathogens; c the VOCs produced by insects’ gut bacteria can attract natural enemies; d VOCs produced by gut bacteria of insects may also repel their natural enemies.

Fig. 4

The vast potential of gut microbiota for pest management.