Data of article entitled Volatile organic compounds diversity mediates tree diversity-insect herbivory relationships

The inconsistent associational effects of plant diversity on insect herbivory suggest underlying mediating factors. Plant volatile organic compounds (VOCs) are important intermediary in plant-plant-insect herbivore interactions, but their roles in associational effects, particularly in linking plant diversity, plant growth and insect herbivory, remain poorly understood. Here, we investigated chewing insect herbivory, leaf VOCs and tree relative growth rates across a tree diversity gradient in a Biodiversity-Ecosystem Functioning experiment in southern China. We aimed to explore whether and how VOCs can mediate the changes in insect herbivory affected by tree diversity, with a specific focus on discerning whether this mediation process primarily involves alterations in the community-level VOCs diversity or changes in VOC emissions from individual trees. Results showed that the mediating effects of VOCs were driven by community-level VOCs diversity rather than individual VOCs emissions. Tree species richness has direct effect on herbivory as well as indirectly influenced herbivory by enhancing community VOCs diversity, which subsequently suppressed tree growth and ultimately reduced insect herbivory