Modelling of auxin transport affected by gravity and differential radial growth.
When a tree stem deviates from verticality, as a result of different environmental factors, patterns of differential radial growth appear. Higher rates of wood production have been observed on the lower side of the tree and lower rates in the opposite side. Biological studies on plant hormones have shown that the concentration of auxin induces radial growth. They also have demonstrated the redistribution of auxin transport in response to gravity. Auxin is then designated as a mediator for differential growth. This paper presents a model for three-dimensional (3-D) auxin transport in conifer trees, which includes gravity dependence. We obtain realistic heterogeneous patterns of auxin distribution over the tree. Then, we propose a law of growth based on auxin concentration to simulate successive differential radial growths. The predicted growths are compared with experimental results of reconstruction of 3-D annual growth of Radiata pine.
Forest
Loïc
L
Laboratoire Techniques de l'Imagerie, de la Modélisation et de la Cognition (TIMC UMR CNRS 5525), Institut d'Ingénierie de l'Information de Santé, Pavillon Taillefer, Faculté de Médecine, 38706 La Tronche cedex, France. loic.forest@imag.fr
Padilla
Fernando
F
Martínez
Salomé
S
Demongeot
Jacques
J
San Martín
Jaime
J
D001692:Biological Transport / Q000502:physiology; D006112:Gravitation; D018522:Gravitropism / Q000502:physiology*; D007210:Indoleacetic Acids / Q000378:metabolism*; D008954:Models, Biological; D064028:Tracheophyta / Q000254:growth & development / Q000378:metabolism*
D007210:Indoleacetic Acids