Techniques for
measuring xylem cavitation and embolism in plants
The techniques for measuring cavitation and embolism
in plant are very diverse but they do not all work well… The reliability of these
techniques is actually a central issue in our field. Here is a recent review on
this topic:
Cochard H, Badel E, Herbette S,
Delzon S, Choat B, Jansen S 2013 Methods for measuring plant
vulnerability to cavitation: a critical review. Journal of Experimental Botany 64:
4779-4791 pdf
Here, I will present two of our favorite techniques
that we use routinely in our lab. The Xyl’em is an apparatus we have designed
primarily to measure xylem embolism via
its effect on loss of xylem conductance. We use it also to measure whole leaf
conductance in its HPFM mode, although this method for measuring Kleaf is no longer recommended. The Xyl’em apparatus is
commercialized by Bronkhorst. We have five of them in the lab,
they work great! The Cavitron was invented to
construct xylem vulnerability curves to cavitation by centrifugation. We have
four of them in the lab.
XYL’EM apparatus
We have developed this apparatus in collaboration with
Bronkhorst. Please visit their site for more information
http://www.bronkhorst.fr/fr/produits/xylem_embolie-metre/
Please report bugs to herve.cochard@clermont.inra.fr
Check for regular
updates!
Important information:
The first Xyl'em+ apparatus were released with flowmeters
of the L13-10S series (range less than 20g/h). These flowmeters appeared to have a high internal pressure drop
which may bias the conductance data. They were later replaced by the L13-10S series
that have a much lower pressure drop. To account for this problem, we have now changed
the position of the flowmeter in the fluid diagram.
We recommend operating this modification.
If you can to use an external flowmeter you should position it on the OUTLET tubing as
below:
Software releases:
XYL’EM and XYL’EM+ apparatus
This new version is compatible with both
apparatus (enter setup first!). XylWin will no longer be update. We invite all users
to update to this new version that solves a number of bugs reported with
XylWin3.0
XylWin+ 3.3 (November 2015)
A new version that will
fix some problem during the installation. A zip file that contains the executable
files Xylem.exe.
XylWin+ 3.2 (April 2014)
This version fixes a problem caused by electrical
interferences with other apparatus that can disconnect the USB communication.
It is now recommended to move away such apparatus (like pumps) from the Xyl’em
box.
XylWin+ 3.1 (October 2013)
· A missing DLL is now included
· mmol/kg selection fixed
XylWin+ 2.0 (December
2012)
Here is the manual of this
apparatus: pdf
XYL’EM apparatus
Former softwares
to operate the Xyl’em box
You
should uninstall an older version before installing a new one!
Xyl’em.xls An Excel file
to operate the Xyl’em manually
XylDos Works with DOS
or a DOS window in Windows
XylWin 1.1 Works with Windows 98. « Save
as » function not working !
XylWin 2.0 Works with Windows XP
(make sure to use “.” And
not “,” as the decimal delimiter!
XylWin 2.01 Problem with Manual
temperature and Manual LP fixed
XylWin 2.02 A problem with data
display has been fixed
·
Added a switch to select the
INTERNAL or EXTERNAL flowmeters
·
Solved a problem with the “flow” graphic
·
You can now select any COM port in the Setup panel
·
Solved a problem with the “flow-range” bar indicator
·
Problems with the installation of this version have been reported
· A ‘standalone’ version entirely rewritten
· Simply unzip the .zip file in a new Xylem3 directory
· Launch xylem.exe and enter setup menu to configure
your equipment
CAVITRON
We have recently developed this technique for rapid
generation of vulnerability curves. It is base on a centrifuge system.
Here are some technical information about this
technique ppt and papers describing its principles:
·
Cochard H 2002 technique for measuring xylem hydraulic conductance under high
negative pressures. Plant Cell and Environment 25 : 815-819. pdf
·
Cochard H, Damour G, Bodet C, Tharwat I,
Poirier M, Améglio T 2005 Evaluation of a new centrifuge technique for
rapid generation of xylem vulnerability curves. Physiologia Plantarum 124:410-418
pdf
A number of artefacts or flaws with this
technique have been reported.
· Beikircher B, Ameglio T, Cochard H,
Mayr, S (2010) Limitation of the Cavitron technique by conifer pit
aspiration. Journal of Experimental Botany 61: 3385-3393 pdf
· Cochard H, Herbette S, Barigah T, Badel E, Ennajeh M, Vilagrosa A 2010. Does sample length influence
the shape of xylem embolism vulnerability curves? A test with the Cavitron
spinning technique. Plant Cell and
Environment 33: 1543–1552.
pdf
· Cochard H, Badel E, Herbette S, Delzon S, Choat B, Jansen S 2013 Methods for measuring plant
vulnerability to cavitation: a critical review. Journal of Experimental Botany doi: 10.1093/jxb/ert193 pdf
Additional
information can be found in Sylvain Delzon’s site: http://sylvain-delzon.com/?page_id=536
CAVIT-HOME
The “Cavit-Home”
is our high-throughput phenotyping platform for
tree cavitation resistance. Three Sorvall RC5 high speed centrifuges have been
transformed into automatized Cavitrons. The Cavitrons are operated remotely for
more confort and security. We use the
Cavisoft software developed by Regis Burlett in Sylvains’lab http://sylvain-delzon.com/?page_id=542
The Cavit-Home is open for
collaborative studies and you are welcome to use our platform. Please contact
me for further information.