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Colchicine and Figs

Has anyone ever treated figs with colchicine to achieve polyploidy?
Does anyone know of any polyploid figs?
Does the polyploidy improve any aspect of the plant or fruit?

Funny, I was just thinking about this last week.

Personally I'd suggest that amateurs beware of this stuff -- colchicine is a powerful vector to mess around with on a food crop, unless you're someone who is using careful controls.  (i.e. unless you're not just "messing around", but rather making a serious attempt to achieve some goal and willing to invest the appropriate discipline to do it).

OK, putting such considerations aside (i.e. let's assume that you're asking not as an amateur but with some sort of serious interest)... What is your intent in achieving polyploidy in a fig?  What goal?  Just asking about the context/motivation to achieve it.  (Or is it more of a pure research interest... i.e. to see if it can be done?).

Mike   central NY state, zone 5

Clarifying:  I'm not saying that the questions are uninteresting.  I wonder about it too, and would love to hear any known research.  But I have not done even a basic search to see what's been published (did you do that yet?).  However, regardless of curiosity, I'm mindful of the risks involved in colchicine and how it affects DNA, and felt that such cautions well ought to be part of any discussion about it.

So, a quick google search (simple search with the terms "ficus carica polyploidy") turns up many scholarly articles about polyploid common fig research.  (Triploid looks to be common).
A separate google search (simple search with the terms "ficus carica colchicine") also turns up articles.

Mike   central NY state, zone 5 

https://pubget.com/paper/19935916/Presence_of_triploid_cytotypes_in_the_common_fig__Ficus_carica_L__
http://www.academicjournals.org/ajb/Ebooks/May/AJB-%2010%20May,%202012%20Issue.pdf
http://waynesword.palomar.edu/hybrids1.htm

http://www.ncbi.nlm.nih.gov/pubmed/19935916
http://www.nrcresearchpress.com/doi/abs/10.1139/G09-068?journalCode=gen#.UTIz7DAQvJY
http://www.degruyter.com/view/j/abcsb.2011.53.issue-2/v10182-011-0022-3/v10182-011-0022-3.xml


Kinda looks like Panachee might be polyploid.  (Maybe JT too).


Mike   central NY state, zone 5

<edit:  REASONS to STAY AWAY from Colchicine:
                             It causes cancer, birth defects, liver damage, and lots more bad things.
http://www.carnivorousplants.org/cpn/samples/Cult291ColchHaz.htm
http://www.ncbi.nlm.nih.gov/pubmed/20586571
http://www.cancer.gov/drugdictionary?cdrid=39188
Yeah, I know that it's also used in some focused cancer treatments (one of the ironies of life that substances that disrupt healthy cell functions also disrupt cancer cells too in specific ways), and potential other treatments (sort of points out the ways that pharmacological understanding and clinical usage and is not so far developed beyond primitive stages... the specific disruptions are only partially understood yet it is used.  But then, there are people in the world still advocating clinical use of thalidomide, DES, and leeches too.  The brightest research physicians expound on how much remains to be learned before we have a clue about what many widely-used drugs actually do to humans).  And all this from a fairly attractive flowering plant.

Michael,

   Just plain, simple curiosity. Thanks for doing my homework for me. I should have done it myself, but when I have fig questions I go  to The Forum. Well, at least this way the topic gets more exposure.

I would not recommend anyone except for a trained professional to use the stuff, it will cause cancer in humans if exposed to it directly, I am not saying you are suggesting to try it but rather just if people have done it in the past.

@Chivas -- I agree 100%, absolutely.  That's what I was saying in post #2 and post #3.  

So since we both seem to be on a track of making sure that people on this forum see the warning (as if they wouldn't see it when they try to obtain it?  Who knows), I'm posting it here in bold:

Don't play around with colchicine.  Use by a trained professional is one thing, but colchicine is a powerful mutagen.  It damages DNA in unusual ways.  It causes cancer (and many other maladies) in humans.  Use of colchicine by amateurs is not recommended.  Any imagined benefits for amateur fig growers is not worth the risk to your health or your family's health.

Am I overdoing it?  I don't think so.  It's very dangerous stuff.

Mike  

Michael and Chivas

     Thanks for words of warning. I feel a bit irresponsible not mentioning it myself: Kids, do not try this at home. Colchicine is a carcinogen (and, oddly enough, used in the treatment of some cancers.)

     My question was submitted because I I know that colchicine treatment of plants induces polyploidy, often resulting in larger plant segments, bigger fruit, brighter colors. Just wondered if it was ever tried on figs and what the results were. There does not seem to be much literature on it out there.

I just thought I would also mention it since it cannot be mentioned enough for a product so dangerous I think.  

But it's interested that is how we have the oats and wheat today because of it, being that they were treated with it to induce bigger cells and therefore a higher yield.  I wonder which other crops it has been used on, you brought all sorts of questions to my mind about it.

  • djm

Actually I've been thinking of attempting this too for a couple weeks now. If you're concerned about the risk associated with colchicine, oryzalin might be a better alternative. It seems to be safer for animals and easier to obtain. Is it worth the effort? Is applying it to a bud likely to result in the eventual growth of a polyploid branch? Would that yield a more desirable variety? I don't know.

Don't know if any of you has a subscription on Springer (I do not), but here's a reference article that mentions triploid and tetraploid varieties in its abstract (I cannot access the full article).
http://www.springerreference.com/docs/html/chapterdbid/96378.html

Mike

Dale - Colchicine (or more frequently a slight chemical variant called colcemid) is used to arrest growing cells in metaphase so karyotyping can be done on the condensed chromosomes. As others mentioned above, it is extremely toxic stuff and should not be used outside a well controlled laboratory environment. It is also used to induce polyploidy in plants by treating seeds or plant cells growing in tissue culture. The whole plants generated from those sources can have favorable characteristics in terms of fruit size & yield when compared to normal, diploid plants.

As Mike points out, there is a report of naturally occurring triploid figs. The pdf is attached. Great find Mike!!!

In the case of the fig, it does not appear to be known. In some plants, yes. It IS interesting that naturally occurring triploid figs are seen at an appreciable rate (3 of 44 trees examined). It suggests that triploidy confers some advantage to at least some figs that causes them to be selected for propagation. 

Very interesting thread, interesting potential results...maybe... but the dire warnings about the effects from misusing this chemical are horrific.

Assuming that someone other than professionals use this product, is it inhaled, absorbed through the skin...etc?  Is the Colchicine that is used to treat Gout just as toxic?  Can you dissolve a Gout pill and brush it on a growing bud?  Is it safer to use this way?


Just curious.

Frank

DWD,

     Thanks for the article. It was interesting that of the sample population, the triploidy was found in the cultivated selections. That suggests it produces/enhances some features attractive to humans. Also, once again demonstrates that "mistakes" of nature (e. g., incomplete meiosis of pollen gamete) can have adaptive value.  One potential flaw in sampling: if these are "unknown" cultivars, how did they control for duplication?

Frank - Yes, the colchicine used to treat gout is very toxic. It is used on patients with acute gout when non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids are contraindicated or not tolerated. Even with the low doses used, studies show dropping the dose received over 24 hours from 4.8 mg total to 1.8 mg total reduces the adverse effects of nausea, vomiting and/or diarrhea observed in 77% of patients to just 26% of patients. It can get into you either via inhalation or absorption. Inhalation is extremely dangerous. A patient with acute gout is currently prescribed three 0.6 mg pills to take over a few hours. As I understand it, patients need to get new doses as acute gout flares happen. Note that gout is not my expertise, my understanding might be dated even though I doubt it. Anyway, you should not be able to get your hands on any very easily. Brushing it on a bud is unlikely to give one a useful result. At best what you will generate is a shoot with mixed cell types, some diploid (2n), some triploid (3n) and some tetraploid (4n). As far as safety goes, I have used it and colcemid from time to time in my lab. I would only use them in a controlled laboratory environment with established systems for handling and disposing of highly toxic materials.

Dale - Exactly. He did not control for duplication in any obvious way. I would expect to call the 3 triploid plants as individual events and not duplications there must have been something that clearly distinguished the cultivars, green vs bronze vs black figs for instance. Great question. His email is listed. You could contact him and ask.

Stay away from the colchicine!!

DWD2...

Thanks for the answers.  This whole line of experimentation is not for me, but I was just curious.  Besides, I'm not that adventurous.  I'll leave that to the experts.


Frank

@DWD2 - thanks for attaching a copy of the article.  (That's pretty much why I posted the reference... I was kinda hoping that you or one of the others here who has a Springer subscription would do exactly that... when I found the abstract I figured I really wanted to read that one... so thanks for obliging and attaching it!).  I did read it, and as I thought likely, he discussed two pathways to triploidy in his article.  Not surprising, since figs have such a bizarrely complex sexual life.   (I guess bananas are similarly unusual... we could probably go places with Jon's interest in both bananas and figs, but hey, I guess we shouldn't go there :-).

One thing that E. Falistocco doesn't do is name which of his/her accessions were polyploid.  I was hoping he or she would, if only to sate curiosity.  But it hardly matters, since most of the accessions are unnamed (and listed as "unknown" variety).  

Another correction on a point I posted above (post #4) -- I mentioned that it looked like Panachee might be polyploid.  And I suppose it still might be, but the reason that I stated that turns out to be based on a misleading coincidence.  There is an apple cultivar called Panachee, and it is polyploid.  (Apparently a hybrid between a tetraploid and diploid variety).  Turns out there's a set of related apple cultivars all based on Panachee.  So whether or not the Panachee cultivar of ficus carica is polyploid, I cannot say... but my initial reason for suggesting it was based on a mixup over which Panachee was being referenced in a paper, the apple or the fig.  I went back and reread that paper, and it was clearly referencing the apple.  So, as far as my own knowledge stands -- looks like there are common occurrences of polyploidy in ficus carica, but I do not know which varieties/cultivars. 

@Dale and @Frank -- Regarding colchicine pathways into the human body.  Yes, as DWD pointed out there are multiple pathways for colchicine -- it can enter via inhalation, absorption through GI linings (both gastric and intestinal), as well as direct absorption through the skin.  It is pulled from bloodstream by the liver, where it is both concentrated (causing a variety of liver and renal diseases, including sometimes death through complete renal failure) and excreted back to the intestinal tract.  Since it is also absorbed through intestinal walls, it induces a cyclic set of "peaks" in the blood, with several peaks occurring over a period of days.  Its metabolites are an interesting lot in themselves (and there are lots of papers on all of these things, for the medically-minded among you).  Eventually it is both metabolized and excreted, as the rates of reabsorption and metabolizing do a dance of competing processes.  But despite this sort of gross pathology, it is the intracellular action which often causes real issues, because of its disruptive effect on cell division at the molecular level.  (i.e. causing cancer and other pathological processes with DNA... particularly some well documented teratogenic action, aka birth defects).

Really interesting stuff... so toxic and dangerous in multiple ways, yet responsible for vast improvement historically for food crops.  And used for treating cancer too (as I pointed out above and so did Dale.  Though that seems ironic, it's actually fairly common for the simple reason that substances that disrupt healthy cell functions will also usually disrupt cancer cell functions... kind of reinforces how "primitive" (in some sense) our capabilities are at intervening in cellular processes that we can understand but are unable to intervene without killing the patient).  Colchicine not only played a part in the improvement of crops like wheat and oats (as Chivas points out)... it's also one of the big factors in why the cannabis of today is hundreds of times more potent than it was in the 60's.  Of course, a very high price was paid by many children-of-the-60's when it became fashionable for amateur cannabis growers to experiment with colchicine, and for far too many young adults being unmindful of the dangers led to otherwise-rare cancers and diseases.  And it comes from a reasonably attractive flower.  (But like we've been saying:  don't mess with colchicine).

On an up note -- the Falistocco paper really is interesting.  I've written to the professore and if I receive anything interesting in reply I'll post about it.

Mike

First, to be clear, I am not suggesting that anybody try anything! 

This was a subject of mild curiosity some years ago when I read an interesting article about this (but with another species).  The article indicated that oryzalin was much safer to work with and, since it's a pesticide I frequently have on my farm (pre-emergent herbicide), I've thought about trying it but really never got around to trying it since I've just never been anything but slightly curious.  Anyways, the old article I read stated that daylily growers frequently used oryzalin to create more robust flowering.  It stated that it was used at the dilution of 1%, plant roots were wrapped in foil to avoid accidental exposure, and the plant was hung upside down into a bucket of the solution overnight.

I didn't bother to read the pdf article (multi-tasking right now as it is), but I'm curious as to what advantages there may be with the creation of polypoid figs.

Ploidy is the complement of chromosomes in a cell. Think of egg or sperm or pollen. Each normally has one half the number of chromosomes of a whole cell. This number is "n". So a normal cell will have 2n, which we call diploid. Sometimes things go not as we expect and we end up with 3n (triploid) or 4n and so on. Commercial/garden strawberries are 8n or more, which is the best example of which I can think of why we are interested in manipulating the ploidiness of plants.

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