John wrote:

Is there any different in an orchid if it's seed parent and pollen parent
are swapped with each other?


I must be in a responsive mood... Yes.

That is what is the different to be the seed parent and to be a pollen
parent?


Maybe I should elaborate... The pollen parent contributes mainly
genomic DNA to the party. That is the DNA that is in the nucleus of the
cell. However, there are cellular components (organelles) which have
their own DNA. Chloroplasts (plastids) , and mitochondria both have
their own (rather small) genome. The plastids and mitochondria are
contributed (in addition to genomic DNA) by the female parent. If you
were paying attention in genetics class, this is non-Mendelian inheritance.

Same goes in animals by the way, except we don't have plastids.
Mitochondrial DNA is maternally inherited. Sperm (or pollen) is smushed
down small, for portability. Everything gets excluded except for the
nuclear DNA. It is only the female gamete that is large enough to
contain all of the other stuff that is necessary, like mitochondia and
plastids.

I don't know that mitochondrial DNA has that much affect on the
orchid progeny (they are pretty much alike), but plastid DNA encodes for
a lot of the color pigments. There are other more subtle differences
between what the pollen and pod parent contribute, but that is the
easiest to understand example.

Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) When one has insufficient credit to purchase
more orchids, obtain more credit