Fig. 4.

GUS activity of excised Arabidopsis leaves in the cold with 0–90 mM sucrose. (A) Leaves floated on 0–90 mM sucrose solutions in an environment of 4 °C in continuous dark for 2 d or 4 d. (B) Same as (A) except that the leaves were maintained in 16 h photoperiod (light) for 2 d. (C) Leaves from control whole plants in soil in 4 °C in 16 h photoperiod (light) or dark, tested at the same time as leaves in (A) and (B). ANOVA and Tukey's test were used to identify treatment effects; treatments with no letters in common are significantly different [P <0.05; n=3 (A, C) or 5 (B)].