Intact plant MRI for the study of cell water relations, membrane permeability, cell-to-cell and long distance water transport. J Exp Bot

Laboratory of Biophysics and Wageningen NMR Centre, Wageningen University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands.
Journal of Experimental Botany (Impact Factor: 5.53). 02/2007; 58(4):743-56. DOI: 10.1093/jxb/erl157
Source: PubMed


Water content and hydraulic conductivity, including transport within cells, over membranes, cell-to-cell, and long-distance xylem and phloem transport, are strongly affected by plant water stress. By being able to measure these transport processes non-invasely in the intact plant situation in relation to the plant (cell) water balance, it will be possible explicitly or implicitly to examine many aspects of plant function, plant performance, and stress responses. Nuclear magnetic resonance imaging (MRI) techniques are now available that allow studying plant hydraulics on different length scales within intact plants. The information within MRI images can be manipulated in such a way that cell compartment size, water membrane permeability, water cell-to-cell transport, and xylem and phloem flow hydraulics are obtained in addition to anatomical information. These techniques are non-destructive and non-invasive and can be used to study the dynamics of plant water relations and water transport, for example, as a function of environmental (stress) conditions. An overview of NMR and MRI methods to measure such information is presented and hardware solutions for minimal invasive intact plant MRI are discussed.

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    • "Water fluxes during freezing and thawing | Page 3 of 12 radial water fluxes during freeze–thaw events (Zweifel et al., 2000; Améglio et al., 2001, 2003); (ii) nuclear magnetic resonance imaging (MRI) allowing visualization of the liquid water allocation before and after freeze–thaw cycles (Faust et al., 1997; Holbrook et al., 2001; Clearwater and Clark, 2003; Van As, 2007); (iiii) X-ray microtomography to visualize embolism inside plants, and also during freezing; this has been performed previously with drought-stressed plants (Brodersen et al., 2010; Charra-Vaskou et al., 2012a; Dalla- Salda et al., 2014; Torres-Ruiz et al., 2014), and is now becoming a reference technology in order to measure embolism in plants without cutting artifacts (Wheeler et al., 2013; Cochard et al., 2014); and (iv) UE measurement to analyze the dynamics of cavitation events (Ponomarenko et al., 2014) during freeze–thaw cycles (Charrier et al., 2015b). "
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    • "A common observation in all treatments was that after FT, T 2 seemed to decrease. For live tissues, T 2 relaxation time decreased with increasing membrane permeability and size of the cellular compartment (Van As, 2007). Membrane alteration and tissue disruption, owing to crystal formation during freezing, appear to be the main causes of this observation. "
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