Fig. 1

Illustration of the phyllochron process. A Phyllochron dynamics (process) in plant p belonging to genotype lsg. The step curve corresponds to the number of visible leaves over time; the interval between steps corresponds to the time interval between successive leaves denoted \(Y_{y,lsg,p,f}\); the time between sowing and the appearance of leaf f is denoted \(H_{y,lsg,p,f}\), and is equal to the sum of the time intervals between leaves until rank f. Red dots correspond to the time of measurement, when the number of leaves is recorded. B Simulated phyllochron dynamics for six plants from the same genotype (one color per plant). For each plant, the light-colored curve corresponds to phyllochrons over the entire process of leaf appearance, while the dark-colored curve corresponds to phyllochrons for the restricted range of leaf ranks \([f_{\min }, f_{\max }]\) imposed by experimental constraints. The first modeled leaf \(f_{\min }\) determines the boundary between the cumulated phyllochron, which corresponds to the time between sowing and appearance of leaf \(f_{\min }\), and the instant phyllochron which corresponds to all intervals between successive leaves within the \([f_{\min }, f_{\max }]\) range