The effect of thymol on lipid peroxidation TBARS content in tobacco seedlings under Cd stress. The roots of seedlings were treated with water (control), CdCl2 (20 μM), CdCl2 (20 μM) + thymol (100 μM), and thymol (100 μM) for 72 h. (A) The seedlings were excised at the base of the stem and supplied Shiff’s reagent or Evans blue for 6 h through the cut stems. Then the leaves were decolorized with ethanol and photographed with a stereoscopic microscope. Bar = 1 mm; (B) The roots were stained directly with Shiff’s reagent and photographed with a stereoscopic microscope. Bar = 1 mm; (C) Shoots and roots were harvested, respectively, for the measurement of TBARS content. Different letters indicated that the mean values of three replicates are significantly different between the treatments (p < 0.05, ANOVA, LSD).