Fig. 1.

Chlorophyll contents and proline accumulation during dark-induced leaf senescence in Arabidopsis. (A) Total chlorophyll content was measured in a time-course experiment over 6 d of dark-induced senescence in Col-0 (wild-type, WT), prodh1, prodh2, and the prodh1 prodh2 double-mutant. Data are means (±SE) of four independent rosettes from two independent experiments. The time periods T₀, T₂, and T₃ are delineated by the progression of senescence in leaves according to Chrobok et al. (2016). Variations within each time-point were not statistically different (ANOVA, P>0.05). Different letters indicate significant differences in overall chlorophyll content between time-points (ANOVA, P<0.05). (B) Proline content was measured in the same time-course experiments as shown in (A). Data are means (±SE) of four independent experiments. Different letters indicate significant differences between means on individual days (ANOVA, P<0.05).