Leaf shape phenotyping

Most measures were manually performed using ImageJ on pictures made either with the binocular or the confocal microscope. Blade Length is defined as the length between the blade petiole junction and the leaf apex. Tooth With is the distance between two consecutive primary sinuses. Tooth Height is the tooth altitude, which is the distance starting at the tooth tip and meeting perpendicularly the tooth width segment. In order to evaluate the anisotropic tooth growth without taking global leaf growth into account, we normalize Tooth Height by Tooth Width and call this new parameter Tooth aspect ratio. The Sinus Angle is the local angle formed by the blade margin at the distal sinus site (see S2D Fig).

Phenotype quantifications and mean leaf contours in Figs ​Figs4E4E and ​and7E,7E, S3E and S5D Figs were performed using the Morpholeaf application installed on the FreeD software [65,85].

Dissection index (DI) presented in S3E and S5D Fig is defined as DI=Leafperimeter24.π.Leafarea. A perfect circle has DI = 1.