Abstract: To investigate the effects of Cu²⁺ on wheat growth and development, three wheat varieties (Luomai 58, Zhoumai 36, and Xinmai 45) were used as materials in a pot soil culture experiment. Five copper ion concentration gradients (0, 50, 100, 150, 200 mg/kg) were set up to study the changes in malondialdehyde (MDA) content and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the leaves and roots of the three wheat varieties under different concentrations of Cu²⁺ stress. The results showed that with increasing copper ion concentration, the MDA content in the leaves and roots of all three varieties gradually increased. The activities of SOD, POD, and CAT all initially increased and then decreased. This indicated that copper stress caused oxidative damage to both wheat leaves and roots. Luomai 58 exhibited the smallest increase in MDA content and maintained relatively high levels of antioxidant enzyme activities, suggesting that its tolerance to copper stress was stronger than that of Zhoumai 36 and Xinmai 45.

Key words: wheat, copper ion, malondialdehyde（MDA）, antioxidant enzyme