The International Code of Nomenclature for Cultivated Plants

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Guldal

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In an interresting discussion on the status of a cultivar, that somewhat deviated from the commonly seen forms of the same cross (Lc. Mini Purple 'Tamami'), 'Eds' brought some clarification to the question by refering to the rules laid down in the International Code of Nomemclature for Cultivated Plants (ICNCP). (for this discussion in its entirety, see: Lc. Mini Purple)

As the ICNCP seems to be a tool, a ressource of equal interest for professional and hobby growers (like most of us), I hurry to share the following information:
On the homepage of the International Society for Horticultural Science they offer for free a download (PDF-format) of the ICNCP (Scripta Horticulturae #18) - you can also find an orderform for buying it as a hardcover book and support their work:
https://www.ishs.org/scripta-hortic...-nomenclature-cultivated-plants-ninth-edition
 
To check it is fully relevant to orchids with the use of grexes and other peculiarities, I did check and the RHS have this summary / guideline specifically for orchid hybrids,
https://www.rhs.org.uk/plants/pdfs/...id-grex,-groups-and-cultivar-names-guidelines

Nice link eds.

There is a nice line in that document that says 'distinguish an individual within a population'.

So for C. Mini Purple 'Tamami' (for example) ...... the individual will be 'Tamami'.

I will take it that any division or clone of the original of 'Tamami' will be genetically identical to 'Tamami'. If there just so-happens to be a change in genetics - then it won't be 'Tamami' anymore - even if we don't know it (due to uncertainty).

Also importantly - clone means clone ----- not a mericlone that mutated. Anything that became or becomes mutated (changed in genetics - even slightly) won't be a 'clone'.

So a plant having a particular clonal name distinguishes an individual (genetically) from all the other members.
 

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My understanding is that Cattleya percivaliana ‘Mendenhall Summit’ was a unique plant in a population of mericloned ‘Summit’. That plant would then be registered as a unique cultivar. Before that happened, it would have been called ‘Summit’ by most growers? It would be up to us to identify when a mericlone is detectably changed from the original parent. As another example, I have two different plants, bought at two different times, of Cattleya Betty Ford ‘York’ AM, but the plants are detectably different in growth habit and modestly different in flower color/substance/shape. I don’t think this is related to mislabeling of plants but to the variation that sometimes happens with mericloning.
 
terry ----- correct! The situation is due to uncertainty. Not being sure about whether a mericlone is actually a 'clone', which is where things all go pear-shaped. The meri-stem propagation methods that we still use today apparently produces both clones and mutations ------ some probability involved. The clones will have the same DNA as the original, while the others that ended up with mutations won't be clones. It is the situation of a mixed bag - which messes up the system. Not much can be done about this at the moment.

Naming is just invented by people. So I'm thinking that if we can ignore names, and enjoy the orchids and their flowers as they are, then that's really great. The names can at least be useful though - for purposes of discussing and chatting about an orchid and its flowers.
 
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As I said in the other thread, the chances are lots of the mericlones (and every other clone) have some transcription errors.

The difference is some of those errors will be in genes that are expressed and therefore change the appearance of the plant (phenotype) whereas most will be in either areas of junk DNA, non-expressed genes or in expressed genes but they don't change the expressed protein sufficiently to cause a visible change of appearance.

It's why you should ignore this idea of a clone being genetically identical and concentrate on the physical appearance or other physical attributes when deciding if a cultivar needs a new name.
 
eds ...... I know what you mean there. Although, based on the definition of a clone (being genetically identical) ----- some other word should be given or generated, that means something along the lines of 'imperfect copy-attempt'. I just want to not misuse or corrupt words such as 'clone'. A clone is a genetically identical copy-attempt result.

I agree that there's not much (or even anything) we can do about the current system and the current technology --- no cheap and accurate and quick DNA test, and no DNA database bank for accurate DNA references of all the orchids (and also knowing that many original hybrids didn't make it, and other issues). Basically - the system is sort of messed up due to uncertainty. We could however - keep turning a blind eye - and live with it. Which is what we've been doing anyway hehehe. The important thing at least is that we know what's going on, and why the system is messed up. Due to uncertainty, and maybe even due to corrupting definitions of words such as 'clone'.

It all comes back to the key line too ------ distinguishing an INDIVIDUAL from the population (all other members).
 
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I think I like to use the term “mericlone” rather than clone. Mericlone implies the particular process we use with meristematic tissue to get plants. Intrinsic to this process is some genetic shuffling. We all know that identical twins in humans are never completely identical even though they are coming from the same two germ cells. I was reminded today (and commented in another chain going on) that Carter and Holmes, while meristeming Cattleya percivaliana ‘Summit’ found one of the resulting plants to be better in several ways and named this cultivar ‘Mendenhall-Summit’. If we want something truly identical to an original plant, we need a division. A meristem is a gamble - we could get something worse, something equal to, or even something a little better than the original. I agree that it would have been best if in the very beginning there had been a code that designated whether a plant was a division of mericlone. If I remember correctly, Hausermann’s tag used to have a Z designation for seedlings which were mericlones.
 
True terry. Mericlone is the process ----- involving the meristem propagation methods. While 'clonal name' and 'clone' are pretty much very clearly defined ...... the issue is that people strayed down the wrong path from the beginning, because they didn't understand or know until maybe later about what can and does happen with the regular or classical meristem propagation processes. That's why the system and 'clonal name' scheme was in a pickle from the start. But I guess we needed a system ----- otherwise we can't trade, or communicate or talk about orchids very well hehehe. So we just have to live with it. Definitely better than nothing for sure.
 
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Doesn’t “cloning” always use meristematic tissue, and isn’t that the name of the process?

I dislike the (sloppy) broad use of the term to indicate any duplicate, even if a division.

Clone, division, and seed-grown are three, entirely different things in my mind.
 
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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.
 
A clone isn't necessarily produced by cloning as we understand the biological in vitro process. The term clone was around before the cloning process!

Strictly speaking every vegetatively propagated plant is a clone - it just means an identical copy.
 
That is why we need a clear distinction between a division (the vegetatively propagated plant) versus the mericloned plant. However, witch no agreement on how to denote this on a label and with so many uncertain plants out there, we are probably lost anyway. I am only confident that my Paphiopedilum Maudiae ‘Bankhaus’ (aka ‘The Queen’) is a division of the original plant from way back and this is because of provenance AND the fact that slippers are minimally cloned. I couldn’t have much confidence that any classic species or hybrid Cattleya was a true division from the original line.
 
Indeed ----- it is true that the 'cloning' process is a general name we use for attempts at copying ----- with the aims of the process being to make 'clones'. And this is where definition is very important. A clone is an identical genetic copy. Any result that isn't identical to the original in genetics (with emphasis placed on identical) - or sometime in the future mutates - is not a clone or no longer a clone.

In the presence of uncertainty - we can at least make some judgement - as in ------- if an orchid has obvious or noticeable and consistent features that aren't the same as the other assumed 'clones' ------ then that individual orchid should be considered different ---- different from the rest, and also assumed it is not a clone, or is no longer a clone. So that individual should have a different single quotes name - to distinguish it from the other members. Or - when noticeable visible differences are detected ------ putting a question mark on the tag -- or '???' a few question marks, may be useful.

And when we mean 'original' ---- it will mean original at the time of copying attempt ----- because for all we know --- the original could also possibly mutate in the future - not sure hehehe
 
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I agree with you both, Terry and Ed.

For historical reasons it seems that in Cattleyas, the ship has to a large extent sailed. That is, unless you have 100% reliable and trustworthy information on the provenience of the plants (as f.ex. "my grandfather got this plant awarded and it's been in the family's possesion ever since" from someone you really trust).
I don't know, whether it would have helped, if there had been a rule about the designation of mericloned plants from the beginnig? Maybe to some extent, but it seems we are really in the realm of trust here, right?
(By the way, I've seen some European vendors having added an 'mc' to the nametags of some of their Catts - I might be barking up a totally wrong tree, but always assumed, this indicated, that the plant was mericloned?)

For practical purposes, outside of breeding, I wonder, if there are other concerns to worry about for the average hobby grower, than whether he or she has drawn a blank in the meristem lottery, and "won" a plant with inferior quality flowers compared to the mother plant?
 
They add MC (mericlone) ----- for nice information, and respecting customers, and maybe also as a shield or safety ---- so that the customers can understand what they're in for ...... a possible lottery bag thing. It's just to say that the orchid we're getting might not be what we want(ed) to get.

But having said 'mixed bag' and 'lottery' ------ sometimes a grower can end up with something amazing, spectacular, unique/individual. So some good stuff can come out of it too. So luck of the draw ----- can be good for some.
 
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