The year-round dynamic of metabolites accumulation in Pinus sylvestris needles in permafrost zone

Key message Pinus sylvestris growing in permafrost areas demonstrates an ability to support active metabolic processes at temperatures lower than -20℃ as a result of accumulation of certain cryoprotectants and sucrose transport. The year-round dynamics of metabolites in the needles of Pinus sylvestris L. was examined, which may help to assess the biochemical mechanisms of adaptation to the extreme climatic conditions of the permafrost zone. Determination of primary and secondary metabolites with GC–MS, flavonoids with HPLC and temperature logging were performed throughout the year. The metabolomic approach allowed to define the metabolites accumulation of which varied with the naturally occurring seasonal changes. According to that, the metabolic profiles were divided into 4 groups each corresponding to the specific season. This division was mainly caused by the metabolites which contents were high at winter and low at summer, such as melibiose, galactinol, alanine, leucine, and glycine. We suggest a specific importance of sucrose transport in the plant metabolism during both early and late stages of climatic winter. Flavonoids were found to have a protective role at high insolation levels during spring time in the permafrost zone. The results of this study on the year-round dynamics of the content of primary and secondary metabolites in P. sylvestris needles suggest specific changes in biochemical processes because of plant adaptation to the extreme climatic conditions in the permafrost zone.