L-PEACH, an L-systems based model for simulating the architecture and carbon partitioning of growing fruit trees.

摘要

Modelling carbon partitioning is a complex problem because of the dynamic nature and relationships between carbohydrate partitioning, growth and plant architecture. To date there have been no fruit tree simulation models that have attempted to quantitatively model these three processes simultaneously. In this paper, we report on an attempt to develop a detailed model of tree carbon economy in which growth and function of each organ is modelled individually within an architecturally explicit model of canopy growth. L-systems was chosen as the platform for tackling the problem of simultaneous modelling of architecture, carbon partitioning and physiology of growing trees and here we introduce the L-PEACH model. L-PEACH combines the supply/demand concepts of carbon allocation of the previous PEACH model with an L-systems model of tree architecture to create a distributed supply/demand system of carbon allocation in a three dimensional, growing tree. The L-PEACH plant model is expressed in terms of modules that represent plant organs. An organ is represented as one or more elementary sources or sinks for carbohydrates and the whole plant is modelled as a branching network of these sources and sinks, connected by conductive elements. An analogy to an electrical network is used to calculate the flow and partitioning of carbohydrates between the individual components. The model can be used to simulate how crop load, rate of fruit maturity, storage tissue sink capacity, and/or water stress can influence growth and carbohydrate partitioning within a fruit tree..