Unit Presentation

Research of the joint research unit "Integrative Physics and Physiology of Fruit and Forest Trees" relates to the responses of the trees to the abiotic factors. This project is taking into account the architectural and functional aspects of the tree during the annual cycle. The work scales extend from the molecule to the cell, organ and whole tree. The studies are developed by Integrative Physics and Biology approaches and organized by biophysics processes determining the acclimation or survival of the trees:

The "Architecture and Microclimate" team analyses the canopy microclimate by approaching the relations between tree training system or tree cover, structure of the vegetation, distribution of the microclimate, and responses of the plants to the microclimatic conditions. An approach based on the plants or virtual covers in 3D is used to describe the structure of the vegetation, and to model canopy microclimate starting from the physical processes of transfer of mass and energy.

The "Winter Biology of Woody Plants" team studies the factors which determine the survival and the successful acclimation or not of the woody species in the winter conditions. Phenology, cold hardening or freezing and the repair of the winter embolism are mainly studied.

The "Hydraulic architecture and drought resistance of trees" team studies the acclimation of trees in the fluctuating water conditions and resistance to the severe drought. The control of variable hydraulic resistances within the hydraulic architecture of the tree (control of foliar resistances, sensitivity and repair of the summer embolism) are the main topics of studies.

The «effects of MEChanical stresses on the Activity of growth zones» team analyses the acclimation of the structure of the plant to a fluctuating mechanical environment (wind) and the recovery of non lethal mechanical accidents (two processes allowing the trees to hold upright a long time).

The integration of the mechanisms, in terms of coupling of the processes and space and temporal integration, is approached by architectural modelling. Tools for characterization of the architecture of the plants were developed. A model of simulation of water fluxes and carbon allocation, and mechanics behaviour is under development considering the tree as a population of organs in interaction.

Organization chart