The broad-scale accumulated and regulated patterns of leaf functional metabolites in two populations of the medicine-industrial plant Viola philippica

Owing to the limited natural distributions and special medicine-industrial values of Viola philippica, it's urgently needed to explore its population-level differences for promoting the resource utilization efficiencies of this plant. The hypothesis of this study was that different populations of V. philippica plants would have broad-scale differences and interactions of leaf-accumulated metabolites and leaf-colonized bacteria. Hence, two populations (vi-p and vi-j) of this plant were typically collected in China for analyzing multiomics. At first, vi-p and vi-j leaf metabolomes (LMs) were presented with 1,003 metabolites; in contrast of vi-p-LMs, 445 differently accumulated metabolites (DAMs) were identified in vi-j-LMs, with the only up-regulated lipids, vitamin and ketone compounds, the only down-regulated aldehyde compounds, the most up-regulated flavonoids, and the most downregulated phenylpropanoid compounds. In comparative of vi-p leaf transcriptomes (LTs), 4,645 differently expressed genes (DEGs) were identified in vi-j-LTs, which were typically involved in a series of extracellular defenses and secondary metabolic pathways; the DEGs were frequently co-enriched with DAMs in three biosynthesis pathways of phenylpropanoid, flavonoid, and alpha-linolenic acid. Furthermore, these DAMs were also found to have the significant correlations with some different types or/and abundances of leaf-assembled bacteria (DTAB) between vi-p and vi-j leaf-assembled bacterial communities (LABCs). Taken together, this study reveals the broad-scale patterns of regulating vi-p and vi-j leaf DAMs with DEGs and DTAB, suggesting that it's essential of keeping plant-population and -habitat diversities for harvesting population-level DAMs in V. philippica.