Effects of Heavy Metals on the Metabolome of Pinus sylvestris (Pinaceae)

The effects of Cu, Ni, and Cd on the Pinus sylvestris metabolome was studied in experimental conditions by gas chromatography–mass spectrometry (GC–MS). Structural changes in plant metabolite network became detectable on day 6 of exposure to the metals, 3–6 days earlier than visual signs of toxicity developed. Differences at the metabolome level arose earlier in a control group of plants, and specific effects of particular metals on the plant metabolome became distinct on day 9. Both nature and concentration of a metal equally contributed to the plant metabolome clustering. Plant responses (changes in concentrations of individual metabolites) to metal exposure substantially differed depending on the metal concentration (1 or 5 mM) and nature. The effects of Cd and Cu were generally similar, while the effect of Ni was often different. Dynamic changes visualized in plant metabolite matrix reflected the changes in its correlation structure, rather than depending on the set of particular compounds.