Effect of cold stress in the rhizosphere on the activity of antioxidant enzymes in the tissues of Pinus sylvestris

The activities of lipase, peroxidase, IAA-oxidase, superoxide dismutase, and catalase have been comparatively studied in the needles, inner bark of stem and roots of 10-year-old self-sawn Pinus sylvestris trees in Central Siberia under natural conditions and in experiment imitating the effect of permafrost. It is shown that a decrease in the rhizosphere temperature for self-sawn Pinus sylvestris causes not only a change in the morphogenesis of the sprouts of the current year and reduction of the annual ring but also a shift of the natural dynamics of antioxidant enzyme activity to a later time. Before soil thawing, the activity of antioxidant enzymes on the experimental plot weakened thus implying the enhancement of the oxidative stress, while the growth of buds and sprouts is hindered during this period because of the high activity of IAA-oxidase. An active part in the elimination of the oxidative stress consequences belongs to the conjugated pair of antioxidant enzymes superoxide dismutase—catalase.