Upregulation of antioxidant enzymes is a biochemical indicator of abnormal xylogenesis in Karelian birch

AOS enzymes can be biochemical indicators of abnormal xylogenesis in Karelian birch. The elevation of enzymatic activity correlates with the increase in wood figure intensity. The different biochemical strategies of the antioxidant system (AOS) enzymes (superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO)) are described for the first time for various xylogenesis scenarios in Karelian birch (Betula pendula Roth var. carelica (Mercl.) Hamet-Ahti). Studies have shown that figured wood formation is closely associated with the secondary metabolism processes in this woody plant, as reflected in the elevation of the activity of AOS enzymes. Our results demonstrate that AOS enzymes can be used as biochemical markers of figured wood formation during active cambial growth.