porometers

[adwright at iastate.edu]

In <2hq5a4$1rl at mserv1.dl.ac.uk> kearns at MIT.EDU writes:

>Hi everyone,
> I am using a steady state portable porometer to measure stomatal
>conductance and transpiration in Arabidopsis . I was using a clamp with an open
>top. What happens if I use a clamp with a closed top? Why are there open and 
>closed tops?  I suppose I should just call LICOR, but I wanted the input of 
>the stomata list, too. Thanks, Ellen 

The open top would allow the normal conditions of humidity over the leaf 
while you measure the resistance of the other side.  I suspect that a closed
top could favorably affect the water relations so that the other side of the 
leaf (that you are measuring) would show decreased resistance. 
Allen

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