# A transportable MRI sensor to monitor the water status of plants in situ

Guilhem Pagés

► To cite this version:

Guilhem Pagés. A transportable MRI sensor to monitor the water status of plants in situ. 53rd Symposium nuclear magnetic resonance spectroscopy for environment and sustainability, Datur chM Dr Soon Ting Kueh, Président, Institut Kimia Malaysia, Jul 2025, Kuala Lumpur, Malaysia. hal-05213264

HAL Id: hal-05213264

https://hal.inrae.fr/hal-05213264v1

Submitted on 18 Aug 2025

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Distributed under a Creative Commons Attribution 4.0 International License
# A TRANSPORTABLE MRI SENSOR TO MONITOR THE WATER STATUS OF PLANTS IN SITU

Guilhem Pagés<sup>a,b,*</sup>

## Abstract

Grasslands and forests play a crucial role in mitigating global warming due to their significant capacity to store carbon. Water is essential in this process, as it acts as a reactant in converting carbon dioxide into sugars during photosynthesis. In the context of global warming and climate change, understanding how plants manage water is critical. However, there is currently no sensor capable of locally probing water content and its movement directly in plants within their natural environment—i.e., *in situ*.

Magnetic resonance imaging (MRI) is the preferred analytical tool for non-invasive, localized measurement of water properties. To make these instruments transportable, low-magnetic-field devices have been developed,¹ including unilateral magnets.² With such unilateral instruments, the sample is placed at the magnet's surface, and the signal is recorded in a thin slice at a known distance from the surface. By precisely adjusting the magnet's position using a high-precision lift, a 1D image or profile can be obtained. This is the principle behind the NMR-MOUSE.³

Few portable devices have been used to study plant evolution *in situ*.⁴ In this work, we evaluated the potential of a unilateral MRI sensor to characterize the plant's water status directly *in situ*, both in the roots (underground) and branches (aboveground). Our results demonstrate that the measurements are quantitative and consistent across different plant species.⁵ Furthermore, through these non-invasive measurements, we were able to extract key indicators of the plant's water status.

**Keywords:** hydric stress, quantitative, rhizotron, tree, water

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**Figure:** (Left) Example of an *in situ* measurement. The system is fixed on a vector to position the sensor against the tree. (Right) Relationship between MRI signal and the water quantity on *ex situ* branches (circles). A linear relationship was found. *In situ* tree measurements were performed (crosses).

## References

1. Nagata, A.; Kose, K.; Terada, Y. *J. Magn. Reson.* 2016, 265, 129-138.
Meixner, M.; Kochs, J.; Foerst, P.; Windt, C. *J. Magn. Reson.* 2021, 323, 106879.

2. Blümich, B.; Blümler, P.; Eidmann, G.; Guthausen, A.; Haken, R.; Schmitz, U.; Saito, K.; Zimmer, G. *Magn. Reson. Imag.* 1998, 16, 479-484.

3. Rehorn, C.; Blümich, B. *Angew. Chem. Int. Ed.* 2018, 57, 7304-7312.

4. Blystone, S.; Nuixe, M.; Traoré, A.; Cochard, H.; Picon-Cochard, C.; Pagés, G. *Plant Meth.* 2024, 20, 31.

5. Nuixe, M.; Traoré, A.; Blystone, S.; Bonny, J.-M.; Pagés, G., Picon-Cochard, C. *Plant. Soil.* 2024, In press.

<footnote><sup>a</sup>Université Clermont Auvergne, INRAE, UR QuaPA, 63122 Saint-Genès-Champanelle, France.</footnote>

<footnote><sup>b</sup>INRAE, PROBE Research Infrastructure, AgroResonance Facility, 63122 Saint-Genès-Champanelle, France.</footnote>

<footnote>*Corresponding author: guilhem.pages@inrae.fr</footnote>