Fig. 4

Effect of either L:L or D:D free-running light conditions on DF rhythms. Wheat and Brassica seedlings were entrained for 4 days in L:D at 22 °C before sections were cut, plated and imaged. A D:D free run consisted of a loop of 54 min of darkness followed by 5 min of light exposure and then image capture. A L:L free-run consisted of 59 min of light exposure before image capture (a). Boxplots of period (b) and RAE (c) are shown for Brassica and wheat in D:D and L:L conditions where Brassica data is displayed in purple and wheat data in orange. Period and RAE were estimated using FFT NLLS, BAMP dtr, 24–120 h cut-off. Examples of oscillation traces are shown in D:D (black lines) and L:L (red lines) for wheat (d) and Brassica (e). Thick lines represent the mean trace of 6 mean-normalised individuals with error bars representing standard deviations. Estimated individual circadian phases are shown in the clock plot in f where the length of the line reflects the inverse circadian phase error (longer lines imply more confidence in the phase prediction). All phase estimates are relative to 0 where 0 represents entrainment dawn and 12 represents dusk. D:D Brassica (N = 12/18); D:D Wheat (N = 24/24); L:L Brassica (N = 18/18); L:L Wheat (N = 23/24). Data is consistent with additional preliminary experiments which can be seen in Additional file 1: Supplementary materials S11 and S12. Significance codes: ***p < 0.001