Using L‐systems for modeling source–sink interactions, architecture and physiology of growing trees: the L‐PEACH model

Abstract

Summary• Functional-structural plant models simulate the development of plant structure, taking into account plant physiology and environmental factors. The L-PEACH model is based on the development of peach trees. It demonstrates the usefulness of Lsystems in constructing functional-structural models.• L-PEACH uses L-systems both to simulate the development of tree structure and to solve differential equations for carbohydrate flow and allocation. New L-systembased algorithms are devised for simulating the behavior of dynamically changing structures made of hundreds of interacting, time-varying, nonlinear components.• L-PEACH incorporates a carbon-allocation model driven by source-sink interactions between tree components. Storage and mobilization of carbohydrates during the annual life cycle of a tree are taken into account. Carbohydrate production in the leaves is simulated based on the availability of water and light. Apices, internodes, leaves and fruit grow according to the resulting local carbohydrate supply.• L-PEACH outputs an animated three-dimensional visual representation of the growing tree and user-specified statistics that characterize selected stages of plant development. The model is applied to simulate a tree's response to fruit thinning and changes in water stress. L-PEACH may be used to assist in horticultural decisionmaking processes after being calibrated to specific trees.

Developmental Computing

“…[1]; bending of branches due to gravity [2,10,20]; and responses to pathogens or insects [18]. Nevertheless, many modeling problems remain open and require further advancements of the mathematical and computational concepts.…”

CN-Wheat, a functional–structural model of carbon and nitrogen metabolism in wheat culms after anthesis. I. Model description

“…Based on calculations of local light interception, various FSPMs account for the assimilation of carbon, but assimilate partitioning is generally solved using a supply-demand approach whereby the supply synthesized by sources is shared among sinks according to their 'demand' (Luquet et al, 2006;Evers et al, 2010;Sarlikioti et al, 2011;Bertheloot et al, 2011). By contrast, an example of mechanistic treatment of sink-source relations for C has been proposed by Allen et al (2005). Recently, Bertheloot et al (2011) proposed the model NEMA for N economy, whereby physiological processes are dependent on N concentrations and on a pool of mobile N shared by all organs.…”

Combining Finite Element Method and L-Systems Using Natural Information Flow Propagation to Simulate Growing Dynamical Systems

“…This specific feature of L-systems was used in the last decade to develop computational models for which the flow of information propagates in a natural way over the plant structure from component to component, e.g. [1] for the transport of carbon, [15] for the transport of water, and [10,5] for the reaction of plants to gravity. All these algorithms use finite di↵erence methods (FDM) for which the plant is decomposed into a finite number of elements and quantities of interest (water content, sugar concentration, forces, displacements, etc.)…”