Team : Sureau

ANR project, 12/19-12/2023.

Link of project presentation : https://anr.fr/Projet-ANR-19-CE04-0006

Coordinator :  COCHARD Hervé

Context

To better understand carbon sequestration by terrestrial agroecosystems, it is essential to locally measure the quantities of water and the flows of sap rising (xylem) and falling (phloem). For this, magnetic resonance imaging (MRI) is a tool of choice if it is portable. This project aims to develop such a sensor to carry out non-invasive, localized measurements that can be applied directly to plants in their natural environment (in situ).

General presentation

Grassland and forest ecosystems are the two main terrestrial ecosystems that help limit global warming thanks to their strong capacity to sequester carbon. Ascending and descending sap flows play a key role, respectively, in bringing the water needed for photosynthesis and then transporting carbon products to carbon sinks such as wood, roots, or soil. Due to climate change, a better understanding of transport mechanisms is essential. Unfortunately, no sensor currently exists that allows these mechanisms to be studied directly on the plant and in situ. To measure water flows in a non-invasive and localized manner, high-field magnetic MRI is the benchmark analytical method. However, such an instrument cannot be moved and only laboratory measurements can be performed. In recent years, portable MRI sensors have been developed. To make the instrument portable, the device's magnetic field (and therefore its sensitivity) has been significantly reduced. Thanks to a design trick, the signal can be recorded locally, i.e. in a slice a few tens of micrometers thick. The precise movement of the magnet then makes it possible to choose the measurement depth. The objective of this project is to use this technology to develop an MRI sensor to measure the quantity and flow of water on plants directly in their agroecosystem. The sensitivity of this new sensor will be evaluated under different environmental conditions, including water stress, on different plants and different organs (stems, roots).

Partners

EMMAH Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes
UREP Unité Mixte de Recherche sur l'Ecosystème Prairial
QuaPA Qualité des Produits Animaux
PIAF Physique et Physiologie Intégratives de l'Arbre en environnement fluctuant