Metabolic differentiation of Teucrium montanum L. (Lamiaceae) from serpentinite and calcareous habitats

Plant secondary metabolites are ubiquitous in plants and play many physiological and ecological roles. Their species-specific qualitative and quantitative composition can vary within and among populations, and as influenced by environmental and genetic factors. Teucrium montanum L. is defined as a facultative serpentinophyte because, besides serpentinite (SER), it inhabits calcareous (CAL) habitats, where it experiences different physical-chemical soil characteristics (e.g. amount of trace elements, water, thermal regime). This research is conducted towards understanding the influence of the edaphic characteristics of SER and CAL habitats on the variability of methanol-soluble metabolites in T. montanum , aiming to identify high-resolution chemical markers to discriminate between ecotypes. Non-targeted metabolomics resulted in the identification of 95 compounds, mainly organic acids, phenolics, and terpenoids. Qualitative phytochemical composition is clearly differentiated in samples from CAL and SER habitats. The inter-population variability of twenty native populations from CAL and SER soils was investigated by metabolic profiling of aboveground parts targeting seventeen phenolic compounds. The quantitative composition of targeted metabolites varies among populations and is significantly influenced by edaphic factors. However, differences between SER and CAL habitats were statistically significant only for a few metabolites. CAL populations are characterized by higher chlorogenic and syringic acids content, while SER populations contain higher catechin, quercetin and isoquercitrin amounts. These compounds can be used as a fingerprint for a serpentinite/calcareous type of habitat and indicators of corresponding ecotypes of T. montanum . • Edaphic factors shape T. montanum phenolic profiles. • CAL and SER habitats show distinct phenolic fingerprints. • LC/MS reveals ecotype-specific bioactive compounds in T. montanum . • T. montanum exhibits substrate-driven metabolic plasticity and resilience.