Re: Clones (was RE: Romantica Roses)

**m*@netcom.com**

** Reply to note from "Don Corleone" <godfatha@hotmail.com> Thu, 23 Mar 2000 15:14:35 EST
>   
> >From: rose-list-admin@mallorn.com
> >From: "Saxton, Susan" <SSaxton@schwabe.com>
> >Subject: RE: [Rose-list] Re: Romantica Roses

> >I am no plant breeder or horticulturist but this makes some sense to me.
> >Since our plants are not CLONES, but cuttings and where we get our plants
> >determines what cuttings they have come from, it would seem they could be
> >somewhat variable.
>   
> First, let me introduce myself to the list since this is my first post here 
> (I think).  We have a small city garden with minimal prime areas for roses, 
> so we are very selective in what we grow.

Welcome aboard!

> Second, most roses today ARE clones (in the strict sense).  Certainly, all 
> the modern NAMED VARIETIES are clones.  Whether they are produced from 
> cuttings or budding, they are the genetic equivalents of each other.

Perhaps a couple of minimal exceptions are appropriate here.  

All roses in commerce except species are clones.  The general definition of a
species rose is that it will reproduce true from seed (there are some purists
that don't quite accept some roses that reproduce true from seed as species -
example: Rosa chinensis "mutablis", aka 'Mutablis'.)

Obviously, the first plant of a new variety was grown from seed unless it is a
sport.

> There are a couple of very minor exceptions:  (1) Rarely, a variety will 
> MUTATE (rose growers call this a "sport") and produce a different variety.  

A sport is not a mutation to the total plant.  A sport is expressed in a single
cane and may even show on a part of a cane which can have, for example, blooms
of different colors in the same cluster.  Budeyes are removed from the sported
areas for bud grafting or a lateral showing the sport is removed for own root
propagation.

Sports are not to rare.  I see several a year in the San Jose Heritage Rose
Garden.

While the sport may one or more of have many attributes different from its
parent, the two of greatest interest ar color differences and climbing habit.

A special case of a sport is a "reversion".  This occurs when a part of a sport
shows the characteristics of the variety it sported from.  This has allowed
rescue of otherwise extinct varieties!

> (2) very, very old varieties which have been cloned for many generations can 
> show a "genetic drift" and actually produce slightly different strains of 
> the same variety.  I know this has happened with some ancient cultivated 
> plants like figs and grapes.  I don't know if our rose varieties have been 
> around long enough for that.

There are differences of opinion among experts as to whether "genetic drift"
occurs in roses.  Dr. Malcolm Manners believes that "varietal deteriation"
results from virus and that once "indexed" the original characteristics will
return.  I toss coins on this subject while awaiting the results of genetic
research which, for roses, is in the embrionic state.

>   
> And, of course, there are those roses called wild roses or species roses  
> (and their varieties) which grow from seeds and are not clones.
>   
> BTW, can we use HTML in this list or do we have to use just text?

Text only, please.

> I know images are forbidden, but what about tags? 

i would hope they would be short and relevant

Regards,

    Mel

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