Figure 9.
Functional analysis of Arabidopsis Rabe1b in the heat tolerance of mature plants. A, Six-week-old mature plants of wild-type Col-0, the rabe1b-1 mutant, and the rabe1b mutant complemented with the Rabe1b, Rabe1b-GTP, or Rabe1b-GDP transgene were placed in a 45°C growth chamber for 10 h. The heat-treated plants were then moved to a 23°C growth chamber for recovery. The photograph was taken 5 d after the heat treatment. B, Fv/Fm images of fully expanded leaves determined immediately after 0 and 4 h at 45°C. The color code in the images ranged from 0 (black) to 1 (purple). C, Fv/Fm values of fully expanded leaves determined immediately after the indicated hours of heat treatment at 45°C. Means and se were calculated from five replicates. According to Duncan’s multiple range test (P < 0.01), means of Fv/Fm at 0 h do not differ significantly if they are indicated with the same lowercase letter; means of Fv/Fm at 4 h do not differ significantly if they are indicated with the same uppercase letter.