Senescence-dependent changes in leaves 9 and 10 of wild-type Col-0 (black circles) and transgenic plants expressing the TPS gene, otsA (white circles), or the TPP gene, otsB (black triangles). A, Chlorophyll content. B, Fv/Fm. Data are means of four plants ± se. Asterisks indicate significant differences (ANOVA) between the three genotypes for each time point: * P ≤ 0.05, ** P ≤ 0.01, *** P ≤ 0.001. Different letters indicate significant differences between the genotypes (P ≤ 0.05; Tukey’s pairwise comparison).