Antioxidative enzyme activities, lipid peroxidation, and morphological changes of eggplant genotypes under copper stress

(I)n this study, the effects of copper (Cu2+) on morphological changes, malondialdehyde (MDA) contents and antioxidant enzyme activities of four Turkish eggplant cultivars were investigated. These eggplant materials were used in our previous assessed under stress and it has been described to be tolerant and/or sensitive. Tolerant genotypes were 'Burdur Bucak' and 'Burdur Merkez' and sensitive genotypes were 'Giresun' and 'Kemer'. Tolerance mechanisms are complicated, but when a genotype has a high tolerance to any environmental stress factor, then that same genotype could be tolerant to another stress factor. For the investigation of this hypothesis, we used salt-tolerant and salt-susceptible eggplant genotypes for Cu stress treatments. The eggplant seedlings were grown in pots filled with a turf + perlite combination under greenhouse conditions. At the 4-5 true leaf stage eggplant seedlings were subjected to 200 mu M Cu stress. Forty days after the Cu stress treatment young plants were harvested and shoot and root fresh and dry weight, shoot and root length, and leaf area were determined. It was found that there were differences among eggplant genotypes in terms of Cu tolerance. On the other hand, this study showed that tolerant genotypes had more tolerance to excess Cu than the sensitive eggplant genotypes. Also, MDA, superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase activities were measured. All of the parameters showed differences among eggplant genotypes with Cu application.