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Old 05-09-2004, 01:51 PM
Ray
 
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As to your first point about selfing, you are absolutely correct that the
genetic percentages could be redistributed differently, but remember that
the hybridization of orchids has been going on a lot longer than we have
even known about genetics, so Violet Charm x Violet Charm = Violet Charm, by
convention.

On your second point, I think you're really oversimplifying the genetics, as
it's not just percentage contributions from parent that make the difference.

Based upon my readings and discussions with folks who really do know this
stuff, (A x B) x (C x D) is very likely not at all equivalent to (A x C) x
(B x D) due to the dominant/recessive issue among others. Look at the
simple A x B cross - offspring can show AB, Ab, aB, and ab gene pairs. Are
they the same hybrid? Yes, Are they "equivalent?" No. Now multiply that
single gene by the total number and the combinations get far more diverse.

That is also why your African Queen vs. Lee Koi Choon example fails. Going
back to your (A x B) x (C x D) versus (A x C) x (B x D) example, it is
highly unlikely, but entirely possible that the first cross ends up with
genes entirely from A & C, while the second is B & D, which nobody would
argue to be the same. That, however, lends total validity to your Violet
Charm point!

Then there's pollen versus pod parent issues, in which - apparently (so I've
heard) - some genes come almost exclusively from the pod parent...
--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Books, Artwork, and Lots of Free Info!
..
"Xi Wang" wrote in message
news:Try_c.320131$gE.190596@pd7tw3no...
Hi group,

I was thinking about naming selfed plants, and I can see why Phal ABC 'X'
x self should get a different clonal name - it is not a clone of 'X'.
However, why would it still be called Phal ABC? Let's take a real life
example like Phal Violet Charm = Phal amabilis X Phal sanderiana [1924].
All Phal Violet Charm plants, clearly, will have 50% of its genes from
either parent no matter what the cultivar. If we self the plant, it
produces a genetic spectrum of offspring, some again sharing the 50/50
split of amabilis and sanderiana, but it is also possible, albeit
unlikely, that the progeny of this selfing could result in a plant that
has 100% amabilis genes, whose exact 'clone' with respect to it's alleles,
theoretically could've been obtained through selfing the original amabilis
parent. So, genetically, why would it be logical to call the progeny of
the selfing Phal Violet Charm again? Is this just convention because
otherwise it would get too complicated?

And while I was typing up the above, another question popped into my head.
Suppose we have species A, B, C, and D. Genetically (A x B) x (C x D) is
equivalent to (A x C) x (B x D) right? And yet, since A x B, C x D, A x
C, and B x D would all have different grexes, so would these two second
generation hybrids despite the fact that they are genetically identical in
terms of what percentage of the genes came from where. For example:

Phal. African Queen [1986]
= Phal. (Norman x Princess Kaiulani)
= Phal. ((fasciata x violacea) x (violacea x amboinensis))

Phal. Lee Koi Choon [1987]
= Phal. (violacea x Golden Pride)
= Phal. (violacea x (amboinensis x fasciata))

Percentage-wise, the genetic makeup for both these plants are identical,
so why do we give them different names?

Cheers,
Xi