Fig. 2

Highly expressed genes in the core region were correlated with the content of monoterpenes. a KEGG enrichment analysis of differentially expressed genes in peels, leaves and roots from the core region compared with the non-core region. The upper part of the figure displays the metabolic pathway enriched by the upregulated genes in core regions, and the lower part represents metabolic pathways enriched by the upregulated genes in non-core regions. Node size represents the number of upregulated genes within the pathway, and colour represents the significance of the pathway. ‘Gene count’ represents the number of genes enriched in a pathway. b Correlation-based network between root gene expression (nodes) and monoterpenes (triangles). Node size corresponds to the degree of each monoterpene. The thickness and colour of the edges denote the strength and significance, respectively. Solid and dashed edges indicate positive and negative correlations, respectively. c Cumulative relative abundance of six genes enriched in root samples. Significance is indicated between core and non-core regions by the Wilcoxon rank sum test