Figure 5.

Mutants of OsCNGC14 and OsCNGC16 are chilling susceptible at seedling stage. A, Morphological phenotypes of wild-type (WT), cngc14, and cngc16 seedlings before and after chilling treatment. Seedlings were hydroponically grown at 26°C for 2 weeks and then treated at 6°C for 72 h followed by recovery at 26°C for 2 weeks. Plants were photographed after the recovery. Scale bars = 2 cm. B, Survival rates of the cngc14 and cngc16 mutants after chilling treatment as in A. The data are the means ± sd of three biological replicates (n = 48 for each replicate). Three independent experiments were carried out with similar results. C, Cellular ion leakage with or without 6°C treatment for 72 h in the third leaves of 2-week-old seedlings grown hydroponically at 26°C. Data represent means ± sd from four biological replicates with 12 plants for each line. Asterisks indicate significant difference by Student’s t test (*P < 0.05 and **P < 0.01). D and E, H₂O₂ accumulation detected by DAB staining (D) and cell death detected by trypan blue staining (E) in the third leaves of 3-week-old seedlings grown in soil before and after a treatment of 6°C for 96 h (n = 15). Scale bars = 1 mm.