The International Code of Nomenclature for Cultivated Plants

[southernbelle]

I think Ray is correct in that "cloning" is the general biologic technique that is being used, but with orchids it is meristem tissue that is being chemically provoked to form new plants. The terms clone and mericlone are really synonymous in orchids. I guess the important thing is to realize that although a clone and a division will have identical formal name tags, including carrying any awards that the parent plant may have received, a clone can be modestly different from the parent plant because of things that happen during the cloning process. A clone could unusually be better than the parent plant but it has at least as much chance of being worse. That is why divisions usually command a premium price.

BUT, the rub is in the nomenclature!! Once named, the cultivar of a species cross or hybrid becomes a “clone” and has a “clonal name”. That does nothing but confuse the issue for those of us who are trying to figure all of this out. It feels like sabotage!! Can we petition for terms that don’t overlap and mean different things?

 

[SouthPark]

Reasons it matters:

1. For breeders to know what they are using
2. For awards
3. For sales, so a seller is not overpaying for an original that is really a copy (and maybe inferior)

Must be missing something

I think you pretty much covered it all there terry.

When I was searching for Rlc. Memoria Helen Brown 'Sweet Afton' in Australia, I purchased a plant that had that exact name on the tag, but ended up with a plant that had these flowers. So it turns out not to be what I was searching for. But at the end - ended up absolutely not complaining! I welcomed it. It turned out to be exactly my 'cup of tea' or 'can of coke' ...... and the name in the single quotes ('Sweet Afton m. Splash') is just arbitrary on my tag for it. Very coincidentally - this one is about to flower again soon. Two buds on it at the moment. Almost there.

I grow for pure enjoyment of orchids - pretty much the same as many other orchid growers. Collecting based on their names and their awards has never been in my activities (although, us growers at least need to have a name in order to try acquire the orchid that we want to grow - as in seeing a particular flower, and wishing to grow that orchid to see its flowers at home at our own leisure, as well as the opportunity to care for that orchid).

Regarding award codes ..... I don't put award codes on my orchid tags. But I can definitely understand the point of view of others - breeders, competitors, etc - for needing cultivar names and award codes. Totally respect that.

 

[terryros]

If the mericlone process was perfect, the resulting plants would be identical to a division from the plant and we wouldn’t have an issue. However, biology always searches for variability. How can a single fertilized human egg divide in two and produce twins that are very much the same, but still detectably different in some ways? It is the way organisms do some genetic shuffling and activation/inactivation during cell division in order to produce differences.

If we could do it over again from the beginning of orchid cloning, we would have put a D or C after the cultivar name (and award) to indicate division or clone. Now that this is impossible, we should approach buying a named cultivar like buying art. Is the provenance certain or uncertain? Has it bloomed and shown itself to be almost identical to what we know about the original? When there is uncertainty, maybe we shouldn’t pay premium price for a gamble. Having a certified “piece” (division) of a great plant (tested virus free) should command a high price.

 

[Guldal]

If the mericlone process was perfect, the resulting plants would be identical to a division from the plant and we wouldn’t have an issue. However, biology always searches for variability. How can a single fertilized human egg divide in two and produce twins that are very much the same, but still detectably different in some ways? It is the way organisms do some genetic shuffling and activation/inactivation during cell division in order to produce differences.

If we could do it over again from the beginning of orchid cloning, we would have put a D or C after the cultivar name (and award) to indicate division or clone. Now that this is impossible, we should approach buying a named cultivar like buying art. Is the provenance certain or uncertain? Has it bloomed and shown itself to be almost identical to what we know about the original? When there is uncertainty, maybe we shouldn’t pay premium price for a gamble. Having a certified “piece” (division) of a great plant (tested virus free) should command a high price.

A magnificent summing up and clearly voiced proposal of guidelines/advice how to (somehow) deal with a to some extent unsolveable situation!

I have in the litterature encountered lots of advice on good growing (some better than others) and sometimes also on how to select a plant for beginners, but not really seen this complex topic expounded on.
Terry, I think it would be a sad thing to see your succint advice burried in a thread with a caption, that I guess might appear unappealing to many.
Maybe, at some point in time someone would take the trouble to summ it all up in a thread with a title more 'sexy" title, f.ex. 'Cattleyas - divisions and mericlones: a guideline for buyers'. Could also contain clarification of the different terms and advice on relevant questions to ask the seller.
I think such a summing up could be conceived in a way, that would appeal to people with a newer, but growing interest in Catts, and at the same time also to more experienced Catt-growers. Of course not to professionals and experts, but from the interest, this thread and some other recent threads, where the topic has been raised in the discussion of individual plants, it appears, there is an interest.
A thread 'in these pages' would of course only be for STC-users, but maybe some of the larger orchid societies on both sides of the Atlantic might have an interest in uploading such advice/guidelines on their web page or publish it as an article in their magazines?

PS. A dissemenation of such knowledge might help raising the awareness of buyers, and thus most likely be a help for the serious and honest Cattley-sellers vs. the shadier ones in the business.

 

[southernbelle]

I think Ray is correct in that "cloning" is the general biologic technique that is being used, but with orchids it is meristem tissue that is being chemically provoked to form new plants. The terms clone and mericlone are really synonymous in orchids. I guess the important thing is to realize that although a clone and a division will have identical formal name tags, including carrying any awards that the parent plant may have received, a clone can be modestly different from the parent plant because of things that happen during the cloning process. A clone could unusually be better than the parent plant but it has at least as much chance of being worse. That is why divisions usually command a premium price.

Where this is so frustrating to me is that (I think this is right) a named cultivar (of an original, seedling or mericlone) is referred to as a clone and its ‘name’ referred to as its clonal name. So, as was said, the lack of definition and interchange of terms (clone vs. mericlone) means that we never know what someone is talking about. Since I’m not selling my plants or divisions it doesn’t matter much long term to me, but I like details to be correct so it makes me nuts. Especially when trying to figure this terminology out so I write or say the correct thing. And, so that I understand vendors’ listings.

 

[southernbelle]

A magnificent summing up and clearly voiced proposal of guidelines/advice how to (somehow) deal with a to some extent unsolveable situation!

I have in the litterature encountered lots of advice on good growing (some better than others) and sometimes also on how to select a plant for beginners, but not really seen this complex topic expounded on.
Terry, I think it would be a sad thing to see your succint advice burried in a thread with a caption, that I guess might appear unappealing to many.
Maybe, at some point in time someone would take the trouble to summ it all up in a thread with a title more 'sexy" f.ex. 'Cattleyas - divisions and mericlones: a guideline for buyers'. Could also contain clarification of the different terms and advice on relevant questions to ask the seller.
I think such a summing up could be conceived in a way, that could appeal to people with a newer, but growing interest in Catts, and at the same time also to more experienced Catt-growers. Of course not to professionals and experts, but from the interest, this thread and some other recent threads, where the topic has been raised in the discussion of individual plants, it appears, there is an interest.
A thread 'in these pages' would of course only be for STC-users, but maybe some of the larger orchid societies on both sides of the Atlantic might have an interest in uploading such advice/guidelines on their web page or publish it as an article in their magazines?

PS. A dissemenation of such knowledge might help raising the awareness of buyers, and thus most likely be a help for the serious and honest Cattley-sellers vs. the shadier ones in the business.

AMEN! Terry, I would really encourage (May I say beg?!) you, as well in this area!! But Guidal, Terry is not one to usually publish his extensive research. I’ve been encouraging him to do it with his research on LEDs since I began learning from him. No luck so far.

 

[SouthPark]

How can a single fertilized human egg divide in two and produce twins that are very much the same, but still detectably different in some ways? It is the way organisms do some genetic shuffling and activation/inactivation during cell division in order to produce differences.

Not sure terry. I assume that identical twins have the same DNA - and the differences will just be along the lines of what they're exposed to, and how much they eat. Eg. One might eat more than the other, and hang out out with different friends ---- exposed to different things. Get more or less sun than the other. As long as they don't for some reason have their whole body DNA mutate (X-files stuff) ....... then the two will have the same DNA.

In the presence of uncertainty - such as today, and maybe forever - in the orchid world ------ we could still turn a blind eye on clonal names ....... even when there is uncertainty as to whether an orchid has the same DNA as the 'original' ----- but we definitely shouldn't turn a blind on orchids that are visibly different than the rest of the 'assumed' bunch having the same clonal single quotes name ------ such as an orchid with variegated leaves ---- while none of the countless other members (having the same clonal name tags) have variegated leaves.

 

[Guldal]

Not sure terry. I assume that identical twins have the same DNA - and the differences will just be along the lines of what they're exposed to, and how much they eat. Eg. One might eat more than the other, and hang out out with different friends ---- exposed to different things.

I once had a postcard with a drawing of two scientists, representing the two polar positions in the Nature versus Nurture debate. However one thing they would agree upon was the conclusion: "It's all Mum's fault"!

 

[SouthPark]

I once had a postcard with a drawing of two scientists, representing the two polar positions of the Nature versus Nurture debate. However one thing they would agree upon was the conclusion: "It's all Mum's fault"!

hahahaha!!!!! And 'dad' had no say in it? hehehe

 

[terryros]

I think it is technically first a “cultivar” name, meaning it belongs to a particular plant. I also think that a beginning (some might say “mother”) plant isn’t a clone. A clone is something that comes off of a plant of origin. Once a division has been made or a mericlone created, those plants are now clones of the original.

I will think about making a new summary post of some of this stuff, while linking to this chain as well. I will pass this by Deb to be sure it is hitting the points.

While the starting genetic material of twins is identical, the genetic material is altered differently during stages of growth and differentiation of each individual. We sometimes don’t recognize how important genes being amplified or turned on or off during development can be. This results in important differences in the end organism. I think of the Bryan Brothers tennis players - identical twins, but differences in size, handed-ness, and probably some other things, even though they were raised identically.

 

[SouthPark]

True Terry. But whether a gene is turned on or off ...... plants having the same DNA will ...... have the same DNA set, right?

For orchids, I assume that whatever the DNA set/sequence is of the original plant ---- at that time is ----- a division is expected to have the same DNA sequence, and a clone (according to actual definition of clone) will have the same DNA sequence. Anything that has (or will have later) different DNA will not or no longer be a 'clone'.

What actually matters is what's going on inside the system ------ with the DNA. If there's uncertainty about it, and if there's nothing we can do about that uncertainty for now (or ever) ------ then we just have to make assumptions with the orchid tags.

But certainly ------ if no other countless members has leaf variegation --- while one odd million one out has variegation ----- then we just got to do the normal thing and say ------ it's definitely not the same, and should not have the same clonal name. Because something is visibly and very clearly different with it.

 

[southernbelle]

Not sure terry. I assume that identical twins have the same DNA - and the differences will just be along the lines of what they're exposed to, and how much they eat. Eg. One might eat more than the other, and hang out out with different friends ---- exposed to different things. Get more or less sun than the other. As long as they don't for some reason have their whole body DNA mutate (X-files stuff) ....... then the two will have the same DNA.

In the presence of uncertainty - such as today, and maybe forever - in the orchid world ------ we could still turn a blind eye on clonal names ....... even when there is uncertainty as to whether an orchid has the same DNA as the 'original' ----- but we definitely shouldn't turn a blind on orchids that are visibly different than the rest of the 'assumed' bunch having the same clonal single quotes name ------ such as an orchid with variegated leaves ---- while none of the countless other members (having the same clonal name tags) have variegated leaves.

SouthPark, we have identical twins. DNA testing showed they are identical twins, however have genetic differences. Although they were pretty impossible to tell apart before they became adults and their personalities and styles differentiated, we doubted they were identical as one has a rudimentary third kidney and the other has a mild bleeding disorder (Von Willebrand Factor). Yale Medical wrote it up because it was so unusual to see in identical twins. When they were born, all we knew was that it was a single placenta, shown on x-ray, as it was before amniocentesis and those things. But placentas can fuse, so we were not 100% sure. So, we had DNA testing done. Identical they are, but one carries a variant for a certain disease that the other doesn’t and vice-versa. So, identical in humans does not mean (even though a single egg split) that the DNA one ends up with is identical to the other. Not to ruffle any feathers, but my personal belief is that it should not be surprising. If God didn’t even create two snowflakes alike, each creature certainly would be a unique individual. I think it’s pretty cool, actually... Oh, and another twist is that the testing showed each twin is the mother of the other twin’s children!! Wrap your head around that one. And by the way, DNA can change when subjected to extreme physiological stress. Astronaut Mark Kelly is an identical twin. When he returned from many months (maybe a year) on the Int’l Space Station he was no longer genetically identical to his twin. The physiological stresses of space over that time changed his DNA. Whether or not it will revert in time and he will be identical to his twin again, remains to be seen.

 

[SouthPark]

SB ...... you mentioned they are identical twins but yet have genetic differences. This may be a contradiction in conditions. Identical, but yet not identical.

Think of data file. Copying or cloning or backing up a data file has the meaning of producing a duplicate that has the same information. When we 'clone' an orchid, or make a division - we need to be specific about the word clone. And to be specific ------ we take the definition of it as meaning genetically identical to the original. Any deviation in the sequence ------ then not identical, and not a 'clone' - or 'no longer' a clone.

Now ------ if producing a 'clone' in organisms is possible, then that is fine - so we will be able to say that it is indeed possible to have orchids (the clones) having identical DNA sequence (identical to the original at the time of duplicating attempt). But if it's not possible, then we probably need to form some other naming system - which is probably what terry and you are suggesting.

 

[eds]

As I wrote earlier in this thread and also in this thread, Lc. Mini Purple that spawned this one, clones aren't always genetically identical due to somatic mutations during cellular division.

This happens to all organisms and will have happened in your cells as you grew and lived so that if you were to sequence each cell in your body there would be some (slight) differences in the genome of different cells.

Whether a gene is expressed or not is controlled by other genes and a mutation in these can change expression or different conditions can cause different expression without genetic change.

So identical means they started from an identical source more than them remaining identical, much like our orchid divisions.

 

[SouthPark]

eds ..... thanks for adding that. Does that mean - regardless of division or original or clone ----- all hypothetically having exactly the same DNA at the beginning ------- all three will eventually mutate? I personally don't mind it if that happens, as I only try to find orchids having flowers that are more or less what I aimed to find - and the name is just useful for me to try to find particular orchids with flower features I'm looking for. And even if they were to mutate enough (by chance) to get different features than what I started with ----- then I don't mind too, as I would have at least enjoyed what I had seen (and also would have taken a heap of photographs for nice memories).

 

[Guldal]

Thank you Belle for contributing with your twin story - I think, we can conclude from it and Ed's expounding on it, that genetics is a much more complex thing than most of us imagine!

Maybe, it actually is like snowflakes: all built on a hexagonal foundation, but with myriads of forms - and inuits having hundreds of ways of describing snow!

 

[Ray]

I just took a look at the etymology of the word “clone” and it was coined in 1903 as “clon” to indicate any piece of vegetative material used for asexual reproduction (which might support what I called the “sloppy use”of the word), but it was actually further limited to tissues that were used for grafting, for which a division would not qualify.

While that might support my assessment of broad, sloppy use, if we - the orchid community - could agree to commonly use “clone” as a general term and “mericlone” to indicate a plant grown from meristematic tissue culture, we might be better off.

Hmmm... Reading what I just wrote makes me think we need to differentiate “tissue culture” a different category, as well. Just about every chrysanthemum we’ve ever seen is cultured from stem end cuttings. Not exactly a “division”, but certainly not cultured meristematic tissue, either.

So, knowing that to a plant, the meristematic tissue is a cluster of living, undifferentiated cells (equivalent to “stem cells” in animals) that can develop into pretty much any kind of living tissue, it would seem that - in terms of being identical to the “donor” plant - divisions (including keikies) come the closest, tissue cultured plants (including phal inflorescence culture) would be next, and mericlones being the least reliable.

I suppose tissue-cultured plants are also as identical as divisions, but I suppose the chemical treatments used to induce growth might cause genetic shifting, so I’ll mentally hold onto that difference.

(edit/post script). This is precisely why I really like this forum. We get into discussions of import, and help each other come to agreement or civil, settled-on disagreement, rather than just “Here’s a picture of my flowering plant”, or “Jane, you ignorant ****” commentary.

 

[southernbelle]

SB ...... you mentioned they are identical twins but yet have genetic differences. This may be a contradiction in conditions. Identical, but yet not identical.

Think of data file. Copying or cloning or backing up a data file has the meaning of producing a duplicate that has the same information. When we 'clone' an orchid, or make a division - we need to be specific about the word clone. And to be specific ------ we take the definition of it as meaning genetically identical to the original. Any deviation in the sequence ------ then not identical, and not a 'clone' - or 'no longer' a clone.

Now ------ if producing a 'clone' in organisms is possible, then that is fine - so we will be able to say that it is indeed possible to have orchids (the clones) having identical DNA sequence (identical to the original at the time of duplicating attempt). But if it's not possible, then we probably need to form some other naming system - which is probably what terry and you are suggesting.

All I can tell you is what the DNA report said. Identical twins (monozygotic) that carry variants to certain disease potential as well as the physical anomaly of the 3rd kidney and Von Willebrand Factor. . It is way over my head, obviously, however as Terry mentioned cell division can be interesting in its results.
Re orchids, I’m not suggesting anything. I’m just trying to understand terminology that differentiates one thing from another and find it confusing that a cultivar would have a ‘clonal’ name and be referred to as a clone when it is not a mericlone. When people get serious about growing and start purchasing more expensive plants, it would seem better to me to have them clearly defined so everyone (growers and purchasers) are on the same page. No agenda here, just truly trying to learn something that, in this context, is not at all well defined. And to your point about our taking clone to be a genetically identical copy at the time of duplication, perhaps as DNA research progresses we will find maybe not as genetically identical as we think. The genetic code is made up of other parts that might or might not differentiate. There is still so much, about so much, we don’t know and definitions of words do change. It would seem to me cattleyas should be indicated to be (preferably on the label) mericlones unless specific provenance knows differently. I have purchased original divisions that have it listed on the growers label. If a grower is that sure of a plant being a division of the original plant rather than a mericlones plant, and is willing to put it on his/her label, then that speaks volumes.

 

[eds]

eds ..... thanks for adding that. Does that mean - regardless of division or original or clone ----- all hypothetically having exactly the same DNA at the beginning ------- all three will eventually mutate? I personally don't mind it if that happens, as I only try to find orchids having flowers that are more or less what I aimed to find - and the name is just useful for me to try to find particular orchids with flower features I'm looking for. And even if they were to mutate enough (by chance) to get different features than what I started with ----- then I don't mind too, as I would have at least enjoyed what I had seen (and also would have taken a heap of photographs for nice memories).

The rate of mutation varies with which part of the genome and why type of cells you're looking at but yet they all have a rate of mutation.

This is sometimes called a molecular clock and it is one of the ways you can extrapolate when species diverged from each other (though you tend to use other evidence alongside the rate of mutation as so many factors can influence it).

It's often not a case of the amount of mutation that changes features but where mutations crop up! A single base pair change could have a significant impact in one location whereas lots of mutations in another section might do nothing!

 

[SouthPark]

It's often not a case of the amount of mutation that changes features but where mutations crop up! A single base pair change could have a significant impact in one location whereas lots of mutations in another section might do nothing!

Nice comments eds. Now ------- regarding the amount of mutation ---- that will be linked to location too. Because eventually - one could assume that given a long enough time, eventually something is going to happen in a particular location. Amount also involves time, linked to rate.