Aboveground insect herbivory shapes plant–soil feedback and ecosystem resilience

Abstract The interaction between plants and their surrounding soil ecosystems is complex, with plant–soil feedback acting as legacy effects from previous plants, influencing subsequent plant growth and insect interactions. Recent studies have shown that experiments focusing on individual factors in isolation do not accurately predict the outcomes of these complex interactions. Aboveground herbivores impact the development of root exudates and their surrounding microbiome, suggesting that herbivory indirectly shapes belowground biotic communities. Such impact of insect herbivory on plant–soil feedback is a crucial area of ecological research. Most studies focus on root-associated organisms and their influence on foliar herbivorous insects, and little attention has been given to the reverse interaction-how foliar herbivory affects the soil environment and PSF. This study explores the bidirectional influence of herbivory and PSF, revealing that aboveground insect herbivory can significantly alter plant–soil feedback mechanisms, influencing not only plant performance but also the broader community structure. A holistic approach that integrates soil microbial complexity with insect herbivory is needed to better predict community-level outcomes and enhance plant protection strategies. Our study thus highlighted the need for a community-based perspective when studying interactions among plants, insects and soil microorganisms.