Abstract

A geometrical model of the emergence of a primordium at the shoot apex in dicotyledons is proposed. It is based on recent fundamental results on plant morphogenesis, i.e.:- the emergence is preceded by the reorganization of the microtubules of the cortical cytoskeleton, leading to a new orientation of the synthesis of the cell wall microfibrils; - the resulting global stress is related to the general orientation of the cell growth. So the model sums up the continuous interactions linking the microtubules, the microfibrils and the cell growth axis.