Nodal root innstances (crown and seminal roots)

[Pankaj Jaiswal]

Vincent, Leszek wrote:

> Hi Toby, Pankaj (& others),
> 
>  
> 
> It would seem essential that these terms be brought back. I provide the 
> detailed definitions for these terms from the Zea mays ontology. If 
> you’d like me to offer tweaked definitions for the definitions offered 
> by Toby, based on my Zea definitions, I could attempt those.
> 
>  
> 
> Crown roots - The crown roots are the predominant component of the 
> adventitious root system. They are termed crown roots because they 
> originate from the basal portion of the growing stem known as the crown. 
> The crown roots are subterranean in origin. The first crown roots (4-5), 
> arranged in a whorl, appear at the base of the second internode about as 
> soon as the tip of the coleoptile reaches the soil surface. A few of the 
> subsequent higher internodes may have a similar number of crown roots 
> (in whorls), after which the successive internodes have more and larger 
> crown roots. The crown roots are usually extensively branched, via the 
> production of numerous lateral adventitious roots. Note that the 
> adventitious roots which arise from 2-3 internodes immediately above the 
> soil surface (aerial in origin) are a separate component of the 
> adventitious root system, called 'prop' or 'brace roots'. (Feldman in 
> Freeling & Walbot (eds), 1994. The Maize Handbook, ID#60920; 
> Kiesselbach, ID#59445; Poethig in Sheridan, WF (ed), 1982. Maize for 
> Biological Research, ID#25744; Vincent, ID#165572, 2002)
> 

Most part of this definition can actually go to the comments section. 
However, this raises a question about

# adding new term "brace roots, synonym: prop roots". These are 
different from "crown roots", if I go with Leszek's definition.

# What is "crown"  or "seedling crown" [not the crown of tree]? We need 
to define it somewhere in ontology or add it as synonym to multiple 
terms suggesting that X-plant_part is grouped to form seedling crown. Or 
create a new term "seedling crown" which we all know is not a 
biologically correct term, but can be treated as a bin/grouping term. 
It's children with part of relationships will more precisely tell what 
region is called as "crown".

-Pankaj