A mobile NMR lab for leaf phenotyping in the field

Abstract

BackgroundLow field NMR has been used to investigate water status in various plant tissues. In plants grown in controlled conditions, the method was shown to be able to monitor leaf development as it could detect slight variations in senescence associated with structural modifications in leaf tissues. The aim of the present study was to demonstrate the potential of NMR to provide robust indicators of the leaf development stage in plants grown in the field, where leaves may develop less evenly due to environmental fluctuations. The study was largely motivated by the need to extend phenotyping investigations from laboratory experiments to plants in their natural environment.MethodsThe mobile NMR laboratory was developed, enabling characterization of oilseed rape leaves throughout the canopy without uprooting the plant. The measurements made on the leaves of plants grown and analyzed in the field were compared to the measurements on plants grown in controlled conditions and analyzed in the laboratory.ResultsThe approach demonstrated the potential of the method to assess the physiological status of leaves of plants in their natural environment. Comparing changes in the patterns of NMR signal evolution in plants grown under well-controlled laboratory conditions and in plants grown in the field shows that NMR is an appropriate method to detect structural modifications in leaf tissues during senescence progress despite plant heterogeneity in natural conditions. Moreover, the specific effects of the environmental factors on the structural modifications were revealed.ConclusionThe present study is an important step toward the selection of genotypes with high tolerance to water or nitrogen depletion that will be enabled by further field applications of the method.

Leaf Development Monitoring and Early Detection of Water Deficiency by Low Field Nuclear Magnetic Resonance Relaxation in Nicotiana tabacum Plants

“…The method detected drought stress even before changes were detected by the naked eye, but, in these studies, water stress was applied by stopping watering so that the resulting stress was severe; in addition, when water stress was detected in these studies, most of the physiological parameters had already been affected by the stress. The NMR measurement in this study was very precise and enabled the detection of slight changes in water at the level of the tissue, and these kinds of measurements have already been shown to be possible in the field [63].…”

In-Vivo NMR Spectroscopy: A Powerful and Complimentary Tool for Understanding Environmental Toxicity

“…While low field NMRs suffer from reduced resolution and sensitivity, their low cost and portability make them ideal for field deployment with often nothing more than a power supply required for monitoring. Some examples, include a mobile NMR lab for leaf phenotyping in the field [ 180 ], a portable sensor for monitoring water and sap flow [ 181 ], a device to detect water content in trees [ 182 , 183 ], fast field cycling NMR in plant leaves [ 184 ], as-well as lipid and metabolites profiling in seeds [ 185 ]. Advancement in technologies such as dynamic nuclear polarization in combination with low field NMR [ 186 ], and zero/ultra-low field NMR with optical detection [ 187 ] offer potential for huge increases in sensitivity that would advance low field NMR into a powerful tool for in-vivo analysis and monitoring.…”

Challenges and advances in measuring sap flow in agriculture and agroforestry: A review with focus on nuclear magnetic resonance

“…Addressing such constraints enables realization of an effective portable NMR tool for sap flow measurement. Despite such challenges, some research groups have succeeded in making compact and portable NMR tool so that experiments can be conducted in situ(climate chambers, greenhouses, or the natural environment) rather than transporting plants to the lab (Musse et al, 2017). In 1998, a portable NMR device named NMR-MOUSE (Figure 4iii) was constructed by Blümich et al (1998) and used for a variety of applications, such as analysis of porosity of the materials (Blümich et al, 2010), stratigraphy of paintings in a non-destructive and non-invasive manner (di Tullio et al, 2016), leaf water status (Capitani et al, 2009), and moisture fraction in wood (Casieri et al, 2004).…”