Heavy metal contamination represents a serious threat for terrestrial ecosystems. Thus, theses metals could be accumulated in living organisms. Bean (Vicia faba) plants were exposed, for three months in pots, to increasing nickel concentrations (C1: 150 mg/kg, C2: 250 mg/kg and C3: 500 mg/kg). They were tested for growth inhibition and oxidative stress response in roots and shoots. The examined parameters were biometric measurements, physiological changes (Chlorophyll) and oxidative stress parameters such as catalase (CAT) and glutation-S-transferase (GST) activity as well as malondialdehyde (MDA) content, in booth parts of plants. These findings showed a strong negative effect of C1, C2 and C3 on growth of bean plants. Furthermore, MDA accumulation was higher, especially in roots at the highest doses. In parallel, a crucial decrease was recorded for the activities of CAT as well as the GST. It suggests that MDA content and antioxidant enzymes activation compose an integrative defense system to reduce Ni toxicity in bean plants.
Keywords: Vicia faba, Nickel, biometric measurements, physiological changes, oxidative stress