Violation prooxidative-antioxidant stability at maize shoots at different level of accumulation of cadmium and nickel

In the complex processes of environmental inhibition – one of the strongest factors of biosphere components destruction – an important role is played by heavy metals. Emissions of their bonds from anthropogenic sources, ability to form high local concentrations, chemical stability and ambiguous biological functions, in particular capability of the negative operating on the agrocenosis components, determine the increase of researchers attention to the heavy metals (Kervesan el al., 2001; Laspina et al., 2005; Rucinska-Gwozdz, 2005). In development of general adaptation syndrome of organisms to the surplus heavy metals in an environment one of the first heterospecific conversions there is activating of lipid peroxidation, which results in alteration of plants metabolism both at the cell level and all of organism (Gryshko-Syshchykov, 1999; Platonova-Kostyshin, 2000; Schutzendubel et al., 2001). Bias of prooxidative-antioxidative equilibrium in the conductor of activating of lipid peroxidation is the call to start of stress conversion. It is known together with it, that at unfavorable conditions and, in particular, under action of nickel ions (Pandolfini et al., 1992), manganese (Pands et al., 1987), copper (Luna et al., 1994), cadmium (Platonova-Kostyshin, 2000), fluorine (Gryshko-Syshchykov, 1999), there is activating of lipid peroxidation processes, what the increase of innate of malonyl dyaldehyde testifies to (Dovgalyuk et al., 2002.). However a necessary condition for normal vital cells functions support is balanced between peroxidation, from one side, and by antioxidative activity, from the other. Therefore for uncontrolled oxidation cascades breaking in every organoid antioxidants and antioxidant enzymes systems function, key role among which in chloroplasts and cytozol of higher plants plays ascorbate peroxidase (E.C. 1.11.1.11), which belongs to hemeperoxidases and catalyzes neutralization of hydrogen peroxide. It is set for today, that different stress factors ambiguously influence on enzyme activity. It was investigated by A.Schutzendubel that cadmium increased enzyme activity in the Scots pine (Pinus sylvestris) roots at first, and after a 24-h sentinel exposition declined (Schutzendubel et al., 2001). In the conditions of anoxia at a pea and wheat ascorbate peroxidase activity in the leaves in rose considerably (Mittova-Igamberdiev, 1998). Next to it, at a maize at low temperature stress effects ascorbate peroxidase activity in leaves declines sharply, that limits of its cryophylactic on the ontogenetic development early stages (Hull et al., 1997). However much questions of violation prooxidative-antioxidant plant systems functioning density are unknown at the stress factors action conditions, in particular at the joint effect of heavy metals. Together with it, also the characteristics of cadmium and nickel accumulation are not investigated by the rootage of plants at their compatible function and subsequent distribution of metals in "root-leave" system. Thus, the analysis of literary data allows to establish, that lipid peroxidation processes development and antioxidant enzymes functioning at the conditions of cadmium and nickel joint action on plant organisms until now remains not found out and needs the detailed investigation, that was the goal of our work.