Cross listings: how much does it matter how parents are listed?

[lotis146]

I found two listings for what I thought was the same plant. I've won one and still have chance to get other, thought I'd wind up with it accidentally! Then I realized a small but possibly relevant difference.

First listing: Paph. Lebaudyanum (haynaldianum x philippinense)

Second: Paph. Lebaudyanum (philippinense x haynaldianum)

I understand that typically this order denotes one being the seed parent and the other, the pod. This is maybe a stupid/difficult question to ask as there's no real telling how this may affect the resultant plants, but how much difference can this make? Wondering if it's worth getting both plants or holding off.

[kindrag23]

I have actually never really thought much on this...but it is a great question. How interesting would it be that by having switched parentage creates a totally different bloom color. Can't wait to hear from others on this one.

[RosieC]

Every time you cross two orchids the results will be slightly different, whichever way round the parents are. The variability of a hybrid can depend on the variability of the parent species.

This is why cultivars become popular, because with those you know more exactly what it's going to look like.

That having been said, I have no idea if the direction of the cross has any affect on this at all. The RHS register both directions as the same hybrid name (except for where the odd mistake has been made before these things were computerized) but they record the direction for the plant that was originally registered. That indicates they put some weight in the direction it was made even if not much.

[orchidsarefun]

it would be great if you could see side-by-side pictures of the blooms of these crosses. Conventional wisdom says that the pod/seed parent predominates genetically - so there should be visual bloom differences. You could then choose which one you liked.
If you page through some of the photos on this site
Phalaenopsis primary hybrids.
you will see plenty of differences in the progeny photos. It could be that some breeders did reverse crosses, especially on the older cross photos. I know that on some of the newer photos differences relate to using new and improved ( like alba or flava forms ) "versions". I was going to do a reverse cross of my own to see for myself, but the pod was somehow lost by the USPS out of the mailing envelope. The strange thing about this reverse cross is that the one pod matured far quicker than the cross. The pod on the cross is still "hanging".
I bet someone well versed in genetics can give a more scientific answer.

[Ray]

I am not well-versed in this area, but my minimal knowledge is that there are some traits that are carried on through mitochondrial DNA only, and that is contributed by the "pod parent" (even through it's technically a "capsule", not a "pod"), not through the pollinia.

So, keeping the order correct has some real significance to the outcome, especially if you're breeding for specific traits.

[littlefrog]

Plastids and mitochondria have their own DNA and are maternally inherited. You are familiar with the chloroplast, of course. Other plastids are responsible for other things. Various color pigments are expressed in plastids as well. I think yellows and reds for sure. Are these genes encoded in the nuclear or plastid genome? I don't know, I am trained in animal cell biology, not plants... Perhaps a plant biologist can weigh in. Turns out that to get a functioning mitochondrion (at least, I assume for plastids as well, but animals don't have those so I'm out of my depth), both nuclear and mitochondrial genomes contribute information to the organelle. And most of that comes from the nucleus.

If the genes for color are encoded in the nuclear genome, then it won't matter which way you make the cross. If some are encoded in the plastid genome, then only mom can pass those along.

So... Yes. It can make a difference. In some crosses it could make a huge difference. Although in practice I haven't seen as much difference as I would have expected. A rule of thumb that I have heard is to use the pod parent for color. If you like a color and want to pass it on, make that parent the pod parent if you can. Is that rule true? See above... would depend on where the genes for the desired color reside.

[lotis146]

Thank you everyone. I didn't win the auction but this is an interesting concept to think on in the future. If ever the opportunity comes up to have reverse cross plants again in the future I may be sure to jump on it. Or if I ever decided to breed myself.

Very interesting indeed.

[Optimist]

I tell you what, another hobby of mine is handicapping race horses, and who provides what part of the dna absolutely makes a difference in horses, etc.,. I do not see why plants would be any different.

[tucker85]

I recently bought several hybrid seedlings from Fred Clarke at Sunset Valley Orchids. On three of the hybrids he had done what he referred to as a reciprocal cross. He crossed the two parent plants both ways, once as the pod parent and once as the pollen parent. He said it will be interesting see the difference. I bought reciprocal crosses of three orchids but they're still a year or two away from blooming.

[Fairorchids]

As far as the RHS recording new crosses with pod & pollen source identified, this is simply bookkeeping and carries no hidden meaning.

For Paphs, there are absolutely trait dominance issues. My dad had 100+ of Paph Nitens (insigne x villosum). These were from multiple seed pods, made both ways.

While insigne dominated for color in all cases, there was a wide variety in flower shapes. In most, it was quite obvious which species was the pod parent.

It is on this background, that I have two different seed pods maturing of Paph Arthurianum (Veitch, 1873) right now:

Paph insigne 'Piping Rock' x Paph fairrieanum (std color).
Paph fairrieanum albescent x Paph insigne, var sanderae (also albescent)

I have seen several clones some 40-45 years ago, again made both ways and with a variety of color forms. All were attractive (if you like Paph fairrieanum), so I have elected to recreate this primary cross with modern line bred parents.

I do not need thousands of seedlings, so I did not do reciprocal crosses, just one each way and each color type. I realize that the albescent cross might come out colored. But that is the risk one takes.

Seed pods will go to the lab in 3-4 months. At the moment I plan to order just the min number of replates. If anyone is interested in flasks in late 2015, please let me know.