Pleione : "sudden death" and discussion on "clone"

[robsorchids]

[size=14 Edit by Maggi : 23rd February: I have split this thread off from the general Pleione topic because the subject matter, starting with "sudden death" and moving to a discussion on what is meant and /or understood by "clone".... to a new thread pt][/size]




.......back to the 'sudden death syndrome' theory it definatley does happen, the amount of forrestii that i have heard of that die out for no apparent reason seems quite high, mine included!
that would explain why its not as plentifull as other species, besides the fact it dosent increase as freely as others.
did i type that about maculata? oops if i did! i meant to say that imported maculata tend to sulk, or are very hard to establish, i like to get british grown bulbs where possible

[sjusovare]

Rob, the sudden death syndrome occures here for every species and hybrids, randomly, and seems rather depending on the weather pattern than anything else...
For example, this winter is rather unusually extreme when it comes to temperature, both in the minima and maxima, which puts me in a difficult situation where it is too cold outside or in the greenhouse and too warm inside, and quite frankly they do not like it at all, even in the unheated room where the temperature is around 12 to 15 C, then it's the humidity which is rather difficult to control (forrestii buds already aborted and Brittania 'Doreen' is likely to follow considering that I noticed today that the flower bud has already started to take a purple color while it is still far from being out of the leaf base).
Add to this that depending on the media used, a rather wet or hot summer makes the watering rather difficult depending on the water retention (I've known summers when sphagnum moss was ideal and much better than a mix bark/perlite, and others when it was so retentive that it caused rot even with very rare waterings).
I believe all that does fragilise the plants more than anything and that they are likely to succumb later to various aggressions.

[Slug Killer]

Rob, If something dies it is very much for a specific reason as in temp changes or watering too soon etc. Any plant can die suddenly if not kept correctly. Perhaps I am lucky or I treat them in a different way to you but if they survive the weather we have had this winter, I must be doing something right. Sunny yesterday, snow again here today and there was a hard frost again. Getting fed up with it now.

Finding a seed grown maculata in the UK is very unlikely as even well known Orchid nurseries import them all. I have several flasks on the go but I've been told they can die quite quickly when de-flasked, time will tell.

[JPB]

Although I do not have an explanation for the "sudden death syndrome", I notice that different clones from one species can behave quite differently (growing them under identical conditions, of course). I have clones of P. forrestii which are only surviving and others do flower very well. The same for P. aurita and P. limprichtii.
So maybe try a clone from another supplier and see what happens...

Hans

[Hristo]

Hans, interesting observations. I am not very clear on the width of distribution of Pleione species but if we were talking about european species we would be entering a conversation about provenance. Different 'collections' of the same species growing differently under the same cultural conditions is no great surprise when they come from different altitudes, latitudes etc. We refer to 'clones' of forrestii for instance when we are talking about plants that are not clones at all, but the product of collections at different times and places!

Flowering for me now, Pleione Britannia 'Doreen'

[JPB]

......We refer to 'clones' of forrestii for instance when we are talking about plants that are not clones at all, but the product of collections at different times and places!.....

Chris, I miss your point here. Can you please enlighten me?

Beatiful Pleione on the photograph, BTW!

Hans

[Pascal B]

Hans, I think what Chris means is that only true clones would react the same way in cultivation. A true clone consists of vegetative propagations of a single plant and therefore all plants of that clone share the same genetic characteristics. Just like a cultivar (= selected clone) should be vegetatively propagated, can never be reproduced by seeds and finds its origin in one single plant selected at a point in time. A lot of growers are not familiar with what a "true" clone or cultivar should be and apply these terms incorrectly.

If a supplier offers a "clone" it does not necessarily mean that it is a true clone, it might be a mix of similar looking plants, it is very hard to get that quarantee. Even a collection from a single wild population is usually not a single clone as that implies it was started as a single plant that only reproduced by offsets, an unlikely scenario. So even plants from the same wild population might react differentlty in cultivation due to their different genetic makeup. Or maybe all 3 of us are talking about the same thing but in different words....

[Hristo]

Many thanks Pascal, that is exactly my meaning! I agree, I think we are all thinking the same thing. Growers of other genera demand more information for collection location than we Pleione lovers do!
 
Hans, glad you like her, she's not rare but she is very reliable!

[sjusovare]

only true clones would react the same way in cultivation. A true clone consists of vegetative propagations of a single plant and therefore all plants of that clone share the same genetic characteristics. J

   Actually, it's not totally true, true clones do not necessary react the same way in cultivation. Indeed all plants of a clone share the same genetic characteristics, but after the 2nd generation of cloning they do behave differently because of epigenetic factors.

   2 individuals with the exact same genetic material are still not identical, because at the level of the individuals, genes are not necessary all activated at the same time nor expressed at the same level, depending on the conditions of their environment, which are always, even if just slightly, different.
   Those differences of expression are themselves transmitted during vegetative propagation, so if you clone again you 1st clones, say 'clone 1' and 'clone 2' which have been cultivated in different conditions from one another, the differences will be passed on, and even if the clones of 'clone 2' are cultivated in the exact same conditions as 'clone 1' was, they won't fully revert.

   I hope my babbling makes sense, it's not easy for me to explain this in english

[Pascal B]

Julien, I understand what you are saying but what you are referring to is more than what most forum readers can understand unless they have some background in biology. Epigenetic factors take a long time, if present, to express themselves in such a way that it would explain the different behavior of the plants in cultivation people in this thread talk about.

In this thread we are talking about the more straightforward "botanical" clone which in horticultural terms is restricted to a group of descendants of a single plant derived by vegetative reproduction or apomixis (asexual reproduction without fertilization). It is probably fair to say such a clone would more or less react the same in cultivation to environmental factors.

The artificial proces of cloning is a different matter but is too costly for niche markets like Pleione to be economically viable. As far as I know, tissue culture through the chemicals present in the media can also cause slight genetic mutations but I have no idea if TC is used in Pleione? Most propagation is through seeds or bulbils correct?

[sjusovare]

   Indeed, tissue culture is considered as not economically viable for pleiones (too small market) -my previous post was not about that type of multiplication-  most of the multiplication is done through bulbils and natural increase (divisions).

   I did observe plants issued from bulbils behaving in a different way than their former parents, especially when it came about tolerance to water or temperature (my Pln aurita are specialists for that, half of them suffer much of the slightest lack of water while the others do not.. they're still all originally coming from only one plant I got 10 years ago), I do think it can explain at least some of the differences seen in cultivation, especially when you take in consideration the fact that it has been grown, divided and resold by different growers, some for over a decade if not more, even if originally they all came from the same plant. (if I remember well, during 1 century there has been only 5 clones of formosana in cultivation worldwide for example).

   I do agree with you that for most of botanical species and even hybrids, there were simply so many different plants in cultivation that the variability of the stock accounts more to explain the differences in cultivation, however that doesn't explain the different behavior for selected clones such as Pln vesuvius "Phoenix' which all came from the same only selected plant.

   The mechanism is complex (and perhaps I should not have gone into details which were not really useful), I just meant to say that the way the previous owners of the plants grew them does affect much the way they are going to behave with you, both them and their bulbils, even if genetically they are similar to others in other places and that one would expect their behavior to be identical.

[JPB]

Hans, I think what Chris means is that only true clones would react the same way in cultivation. A true clone consists of vegetative propagations of a single plant and therefore all plants of that clone share the same genetic characteristics. Just like a cultivar (= selected clone) should be vegetatively propagated, can never be reproduced by seeds and finds its origin in one single plant selected at a point in time. A lot of growers are not familiar with what a "true" clone or cultivar should be and apply these terms incorrectly.

If a supplier offers a "clone" it does not necessarily mean that it is a true clone, it might be a mix of similar looking plants, it is very hard to get that quarantee. Even a collection from a single wild population is usually not a single clone as that implies it was started as a single plant that only reproduced by offsets, an unlikely scenario. So even plants from the same wild population might react differentlty in cultivation due to their different genetic makeup. Or maybe all 3 of us are talking about the same thing but in different words....

We agree, and indeed: a clone is a clone and not just another plant/pseudobulb collected at a given locality (your "same wild population"). I did't know that there is some misuse of that word by some people. The definition of clone is quite straightforward IMO

[KBruyninckx]

I did observe plants issued from bulbils behaving in a different way than their former parents, especially when it came about tolerance to water or temperature (my Pln aurita are specialists for that, half of them suffer much of the slightest lack of water while the others do not.. they're still all originally coming from only one plant I got 10 years ago), I do think it can explain at least some of the differences seen in cultivation, especially when you take in consideration the fact that it has been grown, divided and resold by different growers, some for over a decade if not more, even if originally they all came from the same plant. (if I remember well, during 1 century there has been only 5 clones of formosana in cultivation worldwide for example).

   I do agree with you that for most of botanical species and even hybrids, there were simply so many different plants in cultivation that the variability of the stock accounts more to explain the differences in cultivation, however that doesn't explain the different behavior for selected clones such as Pln vesuvius "Phoenix' which all came from the same only selected plant.

Aren't we overcomplicating the matter?
Divisions (or bulbils for that matter) originating from the same clone would all look alike and would in my opinion all react the same way if the environment is exactly the same...

What I mean is simply that your potting mixture, your water (& your method of watering), your fertiliser, your pots used, your geenhouse/windowsill/unheated conservatory, the nighttime & daytime temperature throughout the year (year after year!), the amount of light etc all play a HUGE role on the performance of your plants.

Flower colour, bulb size can be "manipulated" by fertiliser, within all of the fertilizer brands available again there are sometimes only minute differences in the composition but they DO have an effect, your potting mixture is also key as the pH value of this will determine nutrient uptake by your plant.

For years, and I'll talk about orchids in general now, we used a "traditional" orchid fertilizer (NPK 10-4-7 during spring & summer; NPK 4-8-8 during autumn & winter). Over the last couple of year we have experimented with our so-called Akerne's RAIN MIX ( see: http://akerne-orchids.com/rainmix.htm , NPK 13+3+15+11CaO+3MgO) which we now use solely for all our plants (including Pleiones) yearround.
The effect was and is amazing: bulb size on Cattleya's increased, pseudobulbs were also more rigid and plump, this then of course translates into more flowers with better flowers substance and longer flowering period...

Another example talking about the effect of light.
Our Tolumnia hybrids (equitant Oncidiums for those asleep for the last 20 to 30 years   ) will produce (slightly) different coloured flowers in wintertime than compared to the ones produced in summer.
In this group the flowers produced in summer are much more intense in colour and hence more desirable, but with the cool-growing Masdevallia and Dracula it is the exact reverse, flowers produced in wintertime are brighter coloured and larger than the ones produced in summer.... take into account the fact that these originate from around 2000 - 3000 m in the Andes in South America and you'll soon understand why they dislike summertime in Europe (yes, even the sometimes dreary summers we get in Belgium or the UK )

As the conditions that we give to our plants are all different (and cannot be copied to the finest detail!) it is not surprising that some people tend to grow species X or Y better then us, but then again we all, no doubt, grow some others better than they do
Same story with the individual clones, under different conditions the same clone would perform different (better or worse, that is what experience teaches us...).


kind regards,

Kenneth.

[Luc Gilgemyn]

Flowering for me now, Pleione Britannia 'Doreen'

Chris,
Bulgaria... or it's windowsills seem to be way ahead of everybody else this year... 

[Rodger Whitlock]

In his "Plant Propagation" (iirc), Liberty Hyde Bailey, the famous American horticulturist, mentions that in the old days apple varieties were propagated by seed, not by grafting. He then makes the remarkable assertion that the individual twigs on a single apple tree will show as much variation as a group of seedlings.

Bailey was no fool so one cannot dismiss this as an ill-educated remark by someone who didn't know what they were talking about. To me it implies that epigenetic factors are of more weight than usually realized. In fact, it's only within very recent years that the very term "epigenetic" has started to become a meme.

Bailey, of course, didn't use the term epigenetic. His book is of great interest to students of botanical history as it was published just as the impact of Mendel's seminal papers was starting to be widely felt and genetics was still a very simple discipline.