Extended Data Fig. 3. Additional thermomorphogenesis phenotypes in pif mutants.

a-d Hypocotyl length of 7-d-old Col-0 and pif mutant seedlings grown in LD at constant 17 °C, 22 °C and 27 °C (a) (n = 15), in SD at constant 17 °C, 22 °C and 27 °C (b) (n = 23, except for pif4 17 °C and 22 °C with n = 21 and pif7 27 °C with n = 22), in SD at constant 17 °C or with a daytime temperature at 27 °C (c) (n = 24 except for Col-0 27 °C with n= 19 and pif7 27 °C with n = 22) and in LD at constant 17 °C or with a warm midday of 27 °C (d) (n = 20 except for Col-0 17 °C and pif7 27 °C with n = 22), respectively. Seedlings were grown at 40 μmol m^-2 s^-1 in LD and 80 μmol m^-2 s^-1 in SD.

e, f Flowering time of Col-0 and pif mutant plants grown in LD at constant 17 °C or with a warm 37 °C midday (n = 12 except for pif4 pif7 with n = 11). Flowering time was scored as leaves at bolting (e) and days to bolting (f).

g-i Hypocotyl length (g, h; n = 20-25) and stomatal index (SI) (i; n = 12) of 7-d-old and 14-d-old seedlings of two independent PIF7::PIF7-MYC complementation lines in the pif7-1 background, respectively. Seedlings were grown in LD at 17 °C with a warm midday of 27 °C.

Box plots display the 25th and 75th percentile with the median as centre value and whiskers representing 1.5 times the IQR. Letters indicate significance groups; samples with the same letters are not significantly different (2-way ANOVA followed by two-sided Tukey test, p < 0.05). Asterisks indicate samples that are significantly different to Col-0 wild type (One-way ANOVA followed by two-sided Dunnett’s test, * p < 0.05, ** p < 0.01, *** p < 0.001). All experiments were repeated once with similar results.