Intraspecific variation in leaf (poly)phenolic content of a southern hemisphere beech (Nothofagus antarctica) growing under different environmental conditions

Abstract

Nothofagus antarctica (G.Forst.) Oerst. (Ñire) leaves are a valuable source of (poly)phenolic compounds and represent a high-value non-timber product from Patagonian forests. However, information on the variability of their chemical profle is limited or non-existent. The aim of this study was to evaluate the (poly)phenolic variability in Ñire leaf infusions. To this end, diferent tree populations growing under diferent temperature regimes and soil characteristics were considered. Interestingly, a cup of Ñire leaf infusion could be considered as a rich source of quercetin. Signifcant diferences in the (poly)phenolic content, especially in favonoid conjugates and cinnamic acids, were found among the populations studied. These results suggest metabolic variability among the forests studied, which could be related to the species response to its growing conditions, and also provide some clues about the performance of N. antarctica under future climate scenarios. The N. antarctica forests growing in environments with lower frequency of cold and heat stress and high soil fertility showed better infusion quality. This study showed how a South American beech interacts with its local environment at the level of secondary metabolism. In addition, the information obtained is useful for defning forest management strategies in the Patagonian region.