Repulsion pressure model and numerical simulation for spiral phyllotactic patterns of plants

We present biologically motivated simple models to study phyllotaxis patterns. A simplified MaxMin-principle is applied for determining new-born primordium appearance. We propose a new repulsion pressure model to interpret the angle movement of each primordium influenced by the repulsion from all other primordia or from the nearest left and right neighbors. For a large range of growing velocities, both mechanisms can generate uniformly packed patterns under suitable settings of repulsion parameters. Measurement of the pattern uniformity and demonstration of robustness are also provided.