This title appears in the Scientific Report :
2009
Please use the identifier:
http://dx.doi.org/10.1111/j.1469-8137.2009.02919.x in citations.
Functional repair of embolized vessels in maize roots after temporal drought stress, as demonstrated by magnetic resonance imaging
Functional repair of embolized vessels in maize roots after temporal drought stress, as demonstrated by magnetic resonance imaging
Xylem sap under high tension is in a metastable state and tends to cavitate, frequently leading to an interruption of the continuous water columns. Mechanisms of cavitation repair are controversially discussed. Magnetic resonance (MR) imaging provides a noninvasive, high spatial and temporal resolut...
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Personal Name(s): | Kaufmann, I. |
---|---|
Schulze-Till, T. / Schneider, H. U. / Zimmermann, U. / Jakob, P. / Wegner, L. H. | |
Contributing Institute: |
Phytosphäre; ICG-3 |
Published in: | The @new phytologist, 184 (2009) S. 245 - 256 |
Imprint: |
Oxford [u.a.]
Wiley-Blackwell
2009
|
Physical Description: |
245 - 256 |
DOI: |
10.1111/j.1469-8137.2009.02919.x |
PubMed ID: |
19563443 |
Document Type: |
Journal Article |
Research Program: |
Terrestrische Umwelt |
Series Title: |
New Phytologist
184 |
Subject (ZB): | |
Publikationsportal JuSER |
Xylem sap under high tension is in a metastable state and tends to cavitate, frequently leading to an interruption of the continuous water columns. Mechanisms of cavitation repair are controversially discussed. Magnetic resonance (MR) imaging provides a noninvasive, high spatial and temporal resolution approach to monitor xylem cavitation, refilling, and functionality. Spin density maps of drought-stressed maize taproots were recorded to localize cavitation events and to visualize the refilling processes; c. 2 h after release of the nutrient solution from the homemade MR imaging cuvette that received the root, late metaxylem vessels started to cavitate randomly as identified by a loss of signal intensity. After c. 6 h plants were rewatered, leading to a repair of water columns in five out of eight roots. Sap ascent during refilling, monitored with multislice MR imaging sequences, varied between 0.5 mm min(-1) and 3.3 mm min(-1). Flow imaging of apparently refilled vessels was performed to test for functional repair. Occasionally, a collapse of xylem vessels under tension was observed; this collapse was reversible upon rewatering. Refilling was an all-or-none process only observed under low-light conditions. Absence of flow in some of the apparently refilled vessels indicates that functionality was not restored in these particular vessels, despite a recovery of the spin density signal. |