Packings of pavement epidermal cells

During development, epidermal pavement cells influence the structure of leaves by constraining the growth of other leaf tissues. These cells transition from compact polygonal cells early in development to highly aspherical interdigitated shapes in mature leaves. Epidermal pavement cells in mature leaves have shapes similar to jigsaw puzzle pieces and dictate the mechanical properties of the epidermis. We have developed discrete element method (deformable particle) simulations to model the structural and mechanical properties of pavement cells. In particular, we show here that three shape parameters are required to completely specify the non-convex shapes of pavement cells and that the deformable particle simulations are able to recapitulate the average values of these three shape parameters found in x-ray microcomputed tomography images of the leaf epidermis.