Fig. 2

Petal intermediate cells are responsible for floral movement rhythm. a Longitudinal section of flowers showed that several petal layers were all responsive to the photoperiod. The adaxial and abaxial sides of the petals layers were marked, and white dot lines marked the intermediate and bottom segments of petals. b-c Cell morphology of the adaxial and abaxial epidermis at different time points was tracked by scanning electronic microscopy. Individual cell length and width, as well as the ratio of the cell width to the cell length, were quantified in the C chart. More than 85 cells were randomly selected and quantified in the individual samples. Scale bar, 2.5 mm (a), 25 μm (b). Error bar = SEM (c)