Age-related Changes of Some Chemical Components in the Leaves of Sweet Chestnut (Castanea sativa Mill.)

The aim of this study was to investigate the developmental physiology of sweet chestnut trees (Castanea sativa Mill.) of different age groups (≥ 25, ≥ 50, ≥ 100, ≥ 200, and ≥ 400) in the Catalzeytin district of Kastamonu, Turkey. For this purpose, photosynthetic pigments, proline, total soluble protein, glucose, sucrose, total soluble carbohydrate and starch values, malondialdehyde (MDA) and hydrogen peroxide (H2O2) concentration, and also ascorbate peroxidase (APX), catalase (CAT), and superoxide dismutase (SOD) activities were measured in leaf samples. Hence, significant differences were found in the amounts and concentrations of all types of chlorophyll, carotenoid, proline, total soluble protein, glucose, sucrose, total soluble carbohydrate, starches, MDA, H2O2, APX, CAT, and SOD among the trees of different age groups. While the chlorophyll a value was low in young trees, the chlorophyll b value was low in older trees. It was determined that the MDA content was high in old trees, whereas it was low in young trees. While the amounts of glucose, sucrose, total soluble carbohydrate, and starch were highest in ≥ 400-year-old trees, they were lowest in the young trees. Both APX and CAT activities were high in young trees, whereas SOD activity was lowest in ≥ 400-year-old trees.