PiafMunch

The model PiafMunch was designed to simulate the dynamics of photoassimilate transport and partitioning among different sink organs within complex plant architectures. It is based on a discretized representation of the vascular system, including both xylem and phloem pathways which are interconnected. At network nodes, sieve-tube cross-membrane solute and water fluxes are driven by biophysical membrane properties and local solute availability in relation to local metabolism. According to the Münch model, this generates solute gradients within the phloem system, which in turn generate pressure gradients driving long distance transfers. PiafMunch is a semi-compiled Cpp application that provides the modeler with great flexibility to design both the architectural patterns and physiological details of pathways, sinks/sources and boundary conditions, including user-defined dynamic changes in those parameters or conditions. The differential, generally non-linear, equations describing the model are then solved using state-of-the-art algorithms, involving both sparse linear and non-linear solvers The model has been applied to different theoretical systems, e.g. to investigate the effect of water status, as affected by transpiration, on carbon allocation among sinks, or the impact of local unloading/reloading along the pathway on long distance transport. It has been included as the partitioning module in the functional-structural plant model CPlantBox.

The effect of transpiration on carbon allocation in : Lacointe, A., Minchin, P. (2008). Modelling phloem and xylem transport within a complex architecture. Functional Plant Biology, 35 (10), 772-780. , DOI : 10.1071/FP08085