Anyone else subscribe to the Orchid Digest Magazine (not the Orchid Guide
Digest email list)?

In the most recent edition Helmut Rohrl gives a brief discussion on genetics
and inheritance in complex oncid hybrids on page 40 thru 41.

He makes the point that it 'was a widely held belief that an orchid hybrid
cultivar could be precisely described in terms of the percentage of genetic
material contributed by each species ancestor, however remote.'

He goes on to say that in the F2 generation 'we know that for progeny which
are more than one generation removed from the species parent (ie the F2 or
grandchild generation) calculating percentages for genetic inheritance is
meaningless. For these hybrid progeny it is a virtual certainty that some
of these cultivars carry no chromosomal genetic material from a given
grandparent, or older ancestor.'

I'm having trouble agreeing with that.

I *think* I'm having trouble because I'm used to animal genetics where a
limited number of ovae are fertilized and offspring without genes from a
grandparent might not survive past the blastula stage (*G*). However in
orchids, hundreds of thousands of eggs can potentially be fertilized.
Therefore the mathematical realm of possibilities (bell curve or gene
segregation ) can be demonstrated.

I still think, however, that in practice the lack of genetic material would
lead to the decreased fertility seen in complex hybrids (ie its not unususal
for some plants to be poor parental stock or for some crosses to yeild a
minute number of seed or flasks). And that therefore there would indeed be
genetic material from all parental stock in the exisiting offspring , no
matter how far removed.....

Am I wrong? Or am I right in why I'm wrong?

I expect to be wrong because Rohrl is much more brilliant than I am. And
when I was in school genetics was taught simplistically to us undergrads and
DNA theory was in its infancy (the one gene one trait idea is now out the
window, for example)

Thanks in advance

K Barrett