Fig. 3

H₂O₂ and MDA content in tobacco seedlings and the effect of thymol on the lipid peroxidation and cell death in tobacco leaves and roots under salt stress. Tobacco seedlings were treated with water (C), 150 mM NaCl (S), 50 μM thymol (T) or a mixture of both (S + T) separately for 72 h. H₂O₂ content (a) and MDA content (b) in tobacco seedlings were detected using the kit. (c) The roots were stained with Shiff’s reagent for 20 min to indicate lipid peroxidation. (d) The roots were stained with trypan blue for 20 min to indicate cell death. (e) The leaves were supplied with Shiff’s reagent for 6 h to indicate lipid peroxidation. (f) Leaves were supplied with trypan blue for 6 h to indicate cell death in the leaves. Different lowercase letters in a-b indicate that the mean values of three replicates were significantly different between the treatments (P < 0.05, ANOVA, LSD)