pericycle

[Pankaj Jaiswal]

Katica Ilic wrote:

> Pankaj,
> 
> (Related to the sec part of your message), luckily, as we know it,
> pericycle is present only in the root, so we don't
> need to worry about having the term pericycle getting instantiated all
> over the place.
> 
> Katica

That is fine, but then we need to delete the comment saying
"in seed plants it is regularly present in roots and absent in
most stems and leaves". It doesn't say it is absent altogether.

Also while looking in the Essau, it says..
In the stems of higher vascular plants usually no separate layer is 
found between the phloem and the cortex and the term pericycle is then 
applied in the literature to the outermost part of the phloem in which 
the sieve elements are no longer functional.


-Pankaj



> On Tue, 31 Aug 2004, Pankaj Jaiswal wrote:
> 
> 
>>Hi,
>>Here is what I proposed in response to Alison's mail for pericycle
>>
>>---PO:0009075 : plant ontology
>>----i PO:0009011 : plant structure
>>-------i PO:0009003 : sporophyte
>>-----------p PO:0009005 : root
>>--------------p PO:0000258 : root cortex
>>--------------p PO:0020124 : root stele
>>-------------------p PO:0006203 : pericycle
>>-------i PO:0009007 : tissue
>>-----------i PO:0005708 : cortex
>>--------------i PO:0000258 : root cortex
>>--------------i PO:0006203 : pericycle
>>
>>But this is again leading us into a black hole, which we are trying to
>>avoid. The term pericycle is a generic term and we need to create its
>>instances such as
>>-root pericycle
>>-stem pericycle
>>-leaf pericycle
>>
>>In order to make correct lineage the instantiation is required.
>>
>>Current definition and comments sauugest it so..
>>
>># Definition:
>>
>>     * Part of the tissue of the stele located between the phloem and
>>endodermis.
>>
>># Comment:
>>
>>     * In seed plants it is regularly present in roots and absent in
>>most stems and leaves.
>>
>>
>>
>>-Pankaj
>>
>>
> 
> 
> --------------------------------------------------------------------------
> Katica Ilic             		katica at acoma.stanford.edu
> The Arabidopsis Information Resource 	Tel: (650) 325-1521 ext. 253
> Carnegie Institution of Washington 	FAX: (650) 325-6857
> Department of Plant Biology 		URL: http://arabidopsis.org/
> 260 Panama St.
> Stanford, CA 94305
> U.S.A.
> --------------------------------------------------------------------------
> 
> 
> 

-- 
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Pankaj Jaiswal, PhD
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Dept. of Plant Breeding
Cornell University
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      +1-607-255-4109
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