Agron. Sustain. Dev. 26 (2006) 227-232
DOI: 10.1051/agro:2006008

Cadmium and copper toxicity for tomato seedlings

Chamseddine Mediouni, Ons Benzarti, Baligh Tray, Mohamed Habib Ghorbel and Fatma Jemal

Unité de Recherche "Nutrition et Métabolisme Azotés et Protéines de Stress" UR 99/09-20, Faculté des Sciences de Tunis, Université El-Manar, 1060 Tunis, Tunisia

(Accepted 18 May 2006; published online 23 January 2007)

Abstract - We studied cadmium (Cd) and copper (Cu) toxicity in tomato, their accumulation in plant organs and their ability to induce phytochelatin synthesis. The seedlings were cultivated in nutrient solution supplemented with increased concentrations of CdCl₂ or CuSO₄ from 0 to 50 µM. After 7 days of treatment, plants were harvested and the dry weight, the amount of thiobarbituric acid-reactive substances (TBARS), Cd and Cu contents and SH groups rich peptides were determined. We found that Cd and Cu decrease tomato growth, notably at high Cu levels. Cd and Cu concentrations in plant organs increased with applied amounts. Cd and Cu concentrations were the highest in roots. The amount of thiobarbituric acid-reactive substances, that estimate the lipid peroxidation, was increased with heavy metal exposure and was, mainly, higher in roots with Cu treatment.

Key words: Cadmium / copper / lycopersicon esculentum / phytochelatins / thiobarbituric acid-reactive substances

Corresponding author: Chamseddine Mediouni chams_mfr@yahoo.fr

© INRA, EDP Sciences 2006