Seasonal changes in antioxidant level of Scots pine (Pinus sylvestris L.) needles exposed to industrial pollution. II. Enzymatic scavengers activities

Abstract

The involvement of enzymic antioxidant system, superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase in defense reaction to environmental stress evoked by air and soil pollution, was seasonally studied on three populations of Scots pine (Pinus sylvestris L.) growing on experimental areas close two industrial objects in Poland. The first of them (Luboon) is localised near a phosphate fertiliser factory, the second (Glogow) near a copper foundry, and control stand is placed in Kornik. Glogow is the most polluted site, where in 1998 monthly mean daily concentrations was: SO2 - 17 µg·m−3, NOx- 12 µg·m−3 and dust containing heavy metals (Cu, Pb, Cd) - 29 µg·m−3. Trees in Lubon were influenced for many years by high concentration of SO2 and fluor compounds. Few years ago emissions were markedly reduced, but changes in the soil (low pH and high concentration of aluminium ions) still influence the growth of trees. In needles of two populations: 3 (Russia) and 8 (Poland), from the polluted sites Glogow and Lubon, activities of superoxide dismutase (SOD) and guaiacol peroxidase (PO) were significantly higher compared to Kornik. However, in one population (16 - Slovakia), such dependance was not evident. Activity of ascorbate peroxidase (AP) measured in winter was also higher in needles from polluted sites. The results indicated that the sensitivity of free radical scavenging system in Scots pine needles differs among populations.