Seasonal changes in photosynthesis, phenolic content, antioxidant activity, and anatomy of apical and basal leaves of Aristotelia chilensis

Aristotelia chilensis (Mol.) Stuntz is an evergreen species endemic to Chile. It grows in open areas or under tree canopy, and its leaves emerge early spring summer. The objective of this study was determine changes photosynthetic parameters, total phenol content (TPC), antioxidant activity, anatomy apical basal A. during the year. Photosynthesis performance determined by measuring electron transport rate (ETR), quantum efficiency photosystem II (Fv/Fm), photochemical quenching (qP), non-photochemical (NPQ) with a fluorimeter. Leaf extracts were analysed TPC activity. maximum ETR qP recorded summer when photosynthetically active radiation (PAR) at midday higher (1901 1968 µmol m-2 s-1, respectively) than other parts Fv/Fm had typical physiological values both types (about 0.8 all seasons). Also NPQ not influenced kind season In concordance, highest values. contrast, activity winter followed leaves. results suggested that increase PAR (spring) positively affected TPC, which correlated showed morphological adaptations year intercellular spaces palisade parenchyma larger