Growth, lipid peroxidation and antioxidant enzyme activities as a selection criterion for the salt tolerance of maize cultivars grown under salinity stress.

Abstract

Different responses of three maize (Zea mays L.) cultivars SC 129, SC 13 and SC 155 (differently susceptible to salinity stress) in pot experiment were investigated. The rate of oxidative injury on growth, lipid peroxidation and activities of antioxidant enzymes in relation to NaCl-stress were tested. The cv. SC 129 tolerated NaCl up to 100 mM and cv. SC13 up to 50 mM, whereas cv. SC 155 was markedly affected even at the lowest salinity level used. Moreover, the cv. SC 155 died at a concentration higher than 200 mM NaCl. Concomitantly, the activity of antioxidant enzymes catalase, peroxidase, ascorbate, peroxidase and superoxide dismutase in the salt-tolerant cultivars (cv. SC 129 & cv. SC 13) increased markedly during salinity stress, while they were mostly decreased by salinity stress in the salt sensitive cultivar (cv. SC 155). Consequently, this led to a marked difference in the behavior of lipid peroxidation in the three maize cultivars. We concluded that the activities of antioxidant enzymes and lipid peroxidation were associated with the dry mass production and consequently with the salt tolerance of the three maize cultivars.