The relationship of antioxidant enzymes and some physiological parameters in maize during chilling

Abstract

The changes in some physiological parameters of maize seedlings in response to chilling were studied. The emphasis was laid upon their relationship to chilling induced alterations in antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) activity. The exposure of maize seedlings to chilling caused substantial defects in the 4-day-old seedlings and the seedlings with two fully developed leaves, respectively. The membrane semipermeability perturbations and the loss of viability in the young seedlings were observed. Similarly, we found a decrease of chlorophyll content, appearance of necrotic lesions and inhibition of growth in older plants. The measurements of superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase activities provide an evidence of reactive oxygen species formation, that is assumed to be a reason of the found damages. Significant differences between two cultivars were found in the studied parameters. The electrolyte leakage and viability test provided effective methods for the characterization of the chilling tolerance-level in maize cultivars.