ANTIOXIDANT PROPERTIES OF SOYBEAN SEEDLINGS GROWN IN DIFFERENT SOIL TYPES

The purpose of this work was to assess change in antioxidant ability and accumulation of antioxidants in soybean seedlings, as well as some morphological parameters (plant height, shoot and root mass) during abiotic stress. Activity of antioxidant enzymes [superoxide dismutase (SOD; EC 1.15.1.1) and peroxidases (GPX-guaiacol peroxidase and PPX-pyrogallol peroxidase, EC 1.11.1.7)], phenylalanine ammonia lyase (PAL; EC 4.3.1.5), as well as content of non-enzymatic antioxidants (total phenolics, tannins and flavonoids) were analyzed in leaves of soybean seedlings grown in different soil types [mollic vertisol (humic); calcic chernozem (calcic) and haplic fluvisol (calcaric)]. Seedlings grown in fluvisol had significantly higher activity of SOD (7.5-8.6%) and PAL (39.2-43.0%) in leaves, as well as total phenolics and tannins content (8.1-80.7%) in comparison to those grown in chernozem and vertisol. However, soybean grown in chernozem had the most favourable conditions for growth and the highest total flavonoids content (2.3 mg rutin g-1 dry weight). Regardless the difference in response to higher and lower level of soil fertility, soybean seedlings grown in vertisol and fluvisol had similar morphological properties, which showed the great ability of their antioxidant
systems to acclimate to change in soil quality.