The effect of drought on activity of some antioxidative enzymes and lipid peroxidation

The activity of catalase (CAT), ascorbate peroxidase (APX), isozymes pattern of APX and lipid peroxidation were studied using two different maize cultivars (Ankora, drought sensitive, Nova, less sensitive), under sorbitol induced drought conditions (- 1.4 MPa). Increased activities of both H(2)O(2) scavenging enzymes in the roots and CAT in the roots and mesocotyl indicate that roots and mesocotyl were the main sites of the drought-moderated H(2)O(2) production whereas inesocotyl had a higher antioxidative capacity. On the other hand, the decreased activity of both enzymes in the first leaf seemed to be due to the senescence. The activities of the studied enzymes in the second leaf were increased with the exception of CAT activity of cv. Ankora. No differences between cultivars in APX isozymes pattern were found, however differences among the studied organs were observed in both cultivars. Lipid peroxidation under water stress in roots and second leaf increased. Mesocotyl seems to be less affected by toxic effect of hydrogen peroxide.