Figure 3.

DPB3-1-Overexpressing Plants Showed Increased Heat Tolerance.

(A) Expression levels of DPB3-1 mRNA in the three transgenic lines overexpressing DPB3-1.

(B) Growth of DPB3-1-overexpressing plants under normal conditions. The seedlings were grown on agar medium for 21 d and then on soil for an additional 2 weeks. Photographs of 21- and 35-d-old plants are shown. Bars = 1 cm.

(C) and (D) Average radius of the rosette (C) and height of the inflorescence (D) calculated from the plants grown as in (B). The error bars indicate the sd (n = 25). The data were evaluated using one-way ANOVA, and no significant differences were detected (P > 0.05).

(E) Heat stress tolerance of the DPB3-1-overexpressing plants. Seven-day-old seedlings of the vector control and two transgenic lines were treated at 45°C for 50 min. The photograph was taken after a 7-d recovery period at 22°C.

(F) Percentages of surviving plants after the heat stress tolerance test. Each data point is the mean of three experiments, and each experiment included 28 plants. The letters above the bars indicate significant differences between the plants (P < 0.05 according to Tukey’s multiple range test).

[See online article for color version of this figure.]