%0 Journal Article %1 citeulike:5719241 %A Zwieniecki, Maciej A. %A Holbrook, N. Michele %D 2009 %J Trends in Plant Science %K citeulikeExport droughtbolism, freezebolism, refilling, theory, xylem %N 10 %P 530--534 %R 10.1016/j.tplants.2009.07.002 %T Confronting Maxwell's demon: biophysics of xylem embolism repair %U http://dx.doi.org/10.1016/j.tplants.2009.07.002 %V 14

@article{citeulike:5719241, added-at = {2019-03-31T01:14:40.000+0100}, author = {Zwieniecki, Maciej A. and Holbrook, N. Michele}, biburl = {https://www.bibsonomy.org/bibtex/26df43e1d2d1f6d83406f7d54ca369b8e/dianella}, citeulike-article-id = {5719241}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.tplants.2009.07.002}, comment = {(private-note)By contrast, the ability to refill embolized conduits while the bulk of water in the xylem remains under tension [2–4] would allow plants to restore hydraulic conductivity during periods with high demand for water transport capacity. Phloem girdling also leads to a marked decrease in refilling [16,17], an observation that has been interpreted in terms of the potential role of the phloem in supplying energy, osmotica and/or water needed for refilling [4–6] We propose that a continual, albeit small, amount of sugar ''leaks'' from xylem parenchyma cells. In functional vessels, secreted sugars will be carried away with the transpirational stream maintaining a low concentration of sugar in parenchyma walls. Upon cavitation, apoplastic sugar concentrations will increase, rising quickly to levels much higher than would occur even if transpiration ceased but the vessel remained water-filled, providing a detectable signal strictly associated with embolism. suggests that much of this air is pushed out of the vessel in the gas phase Thus, we propose that vessel walls have interlinked gas-filled channels that permit the movement of gases. These passages must be of sufficiently small diameter that they do not seed cavitation, yet sufficiently numerous to support the needed permeability. In addition, It is widely assumed that the water required for refilling is provided by the phloem via parenchyma cells and that water channels and their activity play a key role [18,19,22]. However, whether xylem parenchyma are capable of supplying water for refilling at the required rate has not been addressed. the fact that water would have to flow through other living cells and potentially cross multiple membranes after being supplied by phloem makes it unlikely that a sufficiently large osmotic gradient can be generated for fast refilling to occur. water vapour from neighbouring full xylem condenses on the little beads of moisture from exuded sugars from the xylem parenchyma. Sounds good.}, day = 31, doi = {10.1016/j.tplants.2009.07.002}, interhash = {8b35dca063e8b6e90d838d8a98169fd4}, intrahash = {6df43e1d2d1f6d83406f7d54ca369b8e}, issn = {13601385}, journal = {Trends in Plant Science}, keywords = {citeulikeExport droughtbolism, freezebolism, refilling, theory, xylem}, month = oct, number = 10, pages = {530--534}, posted-at = {2010-02-02 08:03:40}, priority = {4}, timestamp = {2019-03-31T01:16:26.000+0100}, title = {{Confronting Maxwell's demon: biophysics of xylem embolism repair}}, url = {http://dx.doi.org/10.1016/j.tplants.2009.07.002}, volume = 14, year = 2009 }