43. Gartenbauwissenschaftliche Tagung - (DGG) und des

Gemüsebau
Modeling the three-dimensional architecture of the tomato shoot
using L-systems
J. Fanwoua, K. Kahlen und H. Stützel
Universität Hannover, Institut für Biologische Produktionssysteme, FG Systemmodellierung
Herrenhäuser Str. 2, 30419 Hannover
jfanwoua@yahoo.fr
3-D architectural models are essential tools to accurately describe the microclimate in spatially
heterogeneous crops. This work aimed at developing in 3-D space a model of the tomato
shoot architecture. Model construction was based on digitizer and direct plant measurements
of a tropical and a temperate tomato cultivars grown in low (18/24 o C) and high (28/34 o C)
temperature regimes. Temperature sum concept was applied to predict the initiation and expansion
of shoot organs. Theses developmental events were translated into production rules
according to the formalism of Lindenmayer systems (L-systems). The model provided a good
prediction of leaf and inflorescence appearance. For both tomato varieties, simulated as well
as experimental data showed that organ appearance rate expressed in terms of thermal time
remains stable in low and high temperature regimes. Prediction of leaf size reduction under
high temperature treatment by the model agreed with findings from other studies. Thus, the
formalism of L-systems provides an appropriate framework for constructing the architectural
model of the tomato.
BHGL – Tagungsband 24/2006
187