Root exudates

[Tony Travis]

ecoli at cix.compulink.co.uk ("K N and P J Harris") said:
> [...]
> Root exudates don't exist.
> This is strong stuff. Albert Rovira, Jim Lynch and a whole host of > other 
> soil microbiologists had better just pack up their tents and retreat.
> Time lapse photographs of root exudation taken at Long Ashton (copies 
> still available) are not real. Those who claim that between 5% and 25% 
> of the total photosynthate can be released as exudates are wrong ?
> Supporting references would be most welocome.

Hello, Peter.

Sorry, I missed your reply to my message in bionet.plants: the news 
server I use expires articles very quickly. I've just seen your message 
in the www bionet archive ...

I didn't say that root exudate doesn't exist!

I said that it came primarily from the root cap ("... do not normally 
'secrete' anything as such ...") and I do realise how much of the 
available photosynthate that may represent.

If, however, you are saying that there is a specific secretory mechanism 
that actively transports polysaccharides out of the root (ie. different 
to the sloughing off/degeneration of the root cap) then I must admit my 
ignorance.

If there is such a mechanism, that's interesting - tell us about it. 

	Tony.
--
Dr. A.J.Travis,                     |  mailto:ajt at rri.sari.ac.uk
Rowett Research Institute,          |    http://www.rri.sari.ac.uk/~ajt
Greenburn Road, Bucksburn,          |   phone:+44 (0)1224 712751
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