Re: On Cultivars

From: SCHLAUER@chemie.uni-wuerzburg.de
Date: Mon Feb 23 1998 - 18:08:10 PST


Date:          Mon, 23 Feb 1998 18:08:10 
From: SCHLAUER@chemie.uni-wuerzburg.de
To: cp@opus.hpl.hp.com
Message-Id: <aabcdefg721$foo@default>
Subject:       Re: On Cultivars

Dear Rich,

> However, once
> one starts to cross plants that are themselves hybrids, there
> should in theory be significant variation in the offspring.

Why? A breeder does not cross populations with populations but
individuals with individuals. The variation in each hybrid generation
is always between the two parents that constitute the extreme poles
of the range.

> I wonder
> how useful the name will be in the face of this variation.

Exactly as useful as in the parent generation.

> Is this
> one of those cases where there is a lot of "theoretical variation"
> but in practice all (for example) (S. x mitchelliana) x (S. x formosa)
> crosses look pretty much the same?

You do not talk about cultivars in this case. Both hybrids are taxa,
and at least theoretically, the complex hybrid is again a taxon. This
latter taxon will include all intermediates between the species
involved (_S.leucophylla, minor, psittacina, purpurea_).

> On a related note. Are many of the morphologic characters of
> Nepenthes sex linked?

Comparatively little is known about that. _Nepenthes_ hybrids are
mostly intermediate between the parents.

> If they are, then it seems that having
> different names for essentially the same cross (only by opposite
> sexed parents) makes sense.

Not at all if they are treated as taxa. In this case, the direction
(and any repetitions) of the cross is entirely immaterial.

> If not, it seems to me to only add a layer of unnecessary
> confusion.

Not if the plants are described as cultivars. Cultivars are always
selections. They do not automatically include all individuals with
the same or similar parentage, so principally any plant can be
selected as a cultivar irrespective of its similarity to any other
cultivar.

> Anyone know how the orchid growers handle these situations?

In much the same manner as any other growers.

Kind regards
Jan



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