Interaction between Cd K in Some Growth Parameters and Peroxidase Activity of Tomato (Lycopersicon esculentumL.) Seedlings

Tomato (Lycopersicon esculentum L. var. Al-Wejdan) seedlings at 35 days old supplied with CdCl2 (0, 1, 10, 50, 100 mg/kg soil), KCl (0, 20, 40, 60 mg/kg soil) as well as the combinations between these concentrations. Seedlings at 65 day old showed increasing in stem length and diameter by a combination Cd, 100+K, 60 significantly. Whereas, no significant changes in leaves numbers. Seedlings at 95 day old showed no significant changes in stem length or it diameter whereas, leaves numbers increased by combinations Cd,50+K,20 and Cd,50+K,40. Leaf area was stimulated by K (60mg), Cd (100mg) and by many combinations. There was inhibition in chlorophyll content at Cd (100mg) and at a combination (Cd,1+K,20). Peroxidase activity was inhibited by K at (20 60 mg), Cd at 50mg, with all combinations contain K (20mg) except a combination Cd,1+K,20 and increased by Cd at 1mg. There were no significant changes at another combinations comparing with control