Figure 6

Accumulation of MdCIbHLH1 and the effects of MdCIbHLH1 on chilling tolerance in tobacco. (A) The transcript levels of MdCIbHLH1 in transgenic tobacco. The NtACTIN gene was used as a loading control. WT, wild-type; L1, L2 and L3, transgenic tobacco lines. (B) Chilling tolerance of WT, L1, L2 and L3 seedlings. (C-E) Relative electrolyte leakage (C), proline (D) and MDA contents (E) of WT, L1, L2 and L3 seedlings exposed to chilling. (F) Freezing tolerance of WT, L1, L2 and L3 seedlings. (G) The survival ratios of WT, L1, L2 and L3 seedlings exposed to freezing treatment. (H) Chilling tolerance of WT, L1, L2 and L3 adult tobacco plants. The arrow indicates the necrotic leaf margin. (I-J) Relative electrolyte leakage (I) and MDA content (J) in tobacco plants that underwent chilling treatment. Values indicated by the capital letters are not significant at p < 0.01, according to the Duncan's Multiple Range Test.