Fig. 4. Rapid responses of representative Arabidopsis CKX genes in leaves under dehydration.

Leaves from three-week-old Arabidopsis seedlings were exposed to fanning for accelerated dehydration for approximately 15 min to achieve 10% water loss, followed with 0 (15+0), 10 (15+10), 20 (15+20) or 40 (15+40) min of incubation in sealed plastic bags. Detached leaves placed under 100% relative humidity without treatment were used as controls, in which expression levels were set to 1. The Tub8 gene was used as an endogenous reference gene. The error bar indicates the standard error of the mean (SEM) (n = 3 biological replicates), and an asterisk indicates a significant difference between treated leaves and the control (* for p < 0.05, ** for p < 0.01).