The effect of cadmium toxicity on growth, soluble sugars,photosynthetic pigments and some of enzymes in safflower (Carthamus tinctorius L.)

Different species of plants facing various environmental stresses show different physiological responses. Cadmium is a heavy methal that causes oxidative stress in plants. This study investigated the effects of cadmium toxicity on growth,photosynthetic pigments, soluble sugars, activity of peroxidase and catalase enzymes and cadmium accumulation in root and shoot of safflower (Carthamus tinctorius L.) the cultivar of zarghan Fars. The experiment was carried out under hydroponic conditions with 5 treatments (0, 100, 200, 400 and 600 μM) and 4 replicates. Dry weight of root and shoot, chlorophylls a and b and carotenoids, soluble sugars, cadmium accumulation in root and shoot and the activity of catalase and peroxidase in leaf were measurred.The results showed that the maximum accumulation of cadmium occurred in roots followed by leaves. Soluble sugars in root and shoot increased significantly and dry weight of shoots decreased with increasing cadmium toxicity in comparison to control.The reduction of Dry weight of roots, except for 100 μM treatment and the reduction of chlorophyll a and b contents were significant. Carotenoid content except for 100 μM treatment decreased and the reduction for the treatments of 400 and 600 μM were significant. The activity of catalase in leaf decreased significantly for the treatments of 400 and 600 μM. Also the reduction peroxidase activity, except for the treatment of 100 μM was significant.