Does anyone know off-hand, how the naturally occurring concentration (800 - 1,200 ppm in Colchicum bulbs) compares to what is typically used in chromosome-doubling experiments (.5 or 1 percent weight/volume). Is it enough to get an effect, or is it just too dilute??
I found this using a websearch on yahoo-- obviously not pertaining about roses, but could be useful info.
Hum… I found an intresting link about Ginko Biloba having enough colchicine or colchicine like compounds to be found in a women’s plecenta. Since Ginko is very available it would be intresting to play with it this spring.
Enrique
Link: www.generalvitamin.com/displaycontent.asp?filename=assets/content/newswire_2001_09_06_2.htm
Yet another link! Man, how come I could not find any these links before? Here a conversion kit for day lilies that is sold online. I would think that it is ready to use.
Enrique
Yet another link! Man, how come I could not find any these links before? Here a conversion kit for day lilies that is sold online. I would think that it is ready to use.
Enrique
Thanks Enrique!
Shesh-- I used to think that pot smokers were dumb. On the contrary, some are pretty smart. I have found lots of info by typing in “‘Colchine’ and ‘Marijuana’” and got lots of good hits. I think I am going to try the natural bulb method, however I am going to take ALOT more care and attention to make sure that my safety or that of my family never come into peril. I’ve got a bunch of rooted ‘The Fairy’ cuttings. And I’m going to buy a very cheap blender for my use of this experiment that I will destroy later on.
Still looking for a doubled Mermaid…
1,000 ppm = 0.1% by weight.
Baxter
The information is a little hazy. Is the last link suggesting to use this on NEW shoots? What about seeds? Im assuming they’d dry up and croak. My worry is that most rose’s new basals are too tender for this but I could be wrong. If it is new shoots and it actually works, am assuming too much to think that one is supposed to eliminate the other stems manually when the chaemical treated part matures? Sorry if that’s confusing.
-Mike
Mike,
You definitely need to treat “actively dividing cells” (think actively growing) with colchicine or any of the other doubling chemicals. Cells normally double their chromosomes right before dividing; colchicine stops that normal division from occurring, leaving the cell with all the contents of what would have normally been two cells. If the cells are not dividing, you won’t get the desired effect. Same goes for seeds, you need cell division (in other words growth) for the doubling to occur. That’s why people are always treating newly germinated seeds or the growing point between the cotyledons.
You’re right, the chemicals are very destructive to the tender new growth. It’s a fine line between desired effect and toxicity. And when you think you’ve properly treated a shoot you will probably have to cut off other competitive growth to force growth from the treated regions. Often the treatments result in chimeras, (mixtures of doubled and normal cells) because only the cells that were caught at just the right stage of division, and their descendent cells, will have been doubled.
I think the whole process is rather “hocus-pocus” and inefficient; but still, it’s worth all the bother when you get even one success. Maybe a sterile dead-end diploid hybrid could be changed into a fertile new addition to your tetraploid breeding programs. To me, all the trouble seems small in comparison to the rewards.
Thank you, Tom. I would like to try this, most likely with R. Rugosa ‘Alba’ just out of curiousity. Im hoping that the rugosas arent sensitive to this like they are with fungicides. Im thinking early spring would be best as to lessen the heat intensity on them.
-Mike
Jadae, I have read that the more sterile a diploid is, the more fertile the tetraploid, and vise-versa. Since R. rugosa alba is quite fertile, a tetraploid from it might not be very fertile. Still worth a try. If you are just looking for a tetraploid rugosa, email me. I might be able to help you.
Joan
Below is a link you might find interesting along those lines.
Because a fertile branch, on a previously sterile plant would be a pretty definite confirmation that doubling has occurred; I’ve only been trying to convert sterile species hybrids, so far. I’ve been using trifluralin (active ingredient in Preen herbicide) since it was readily available, and supposedly less toxic to mammals (myself included). So far, I’m pretty sure that I’ve gotten two decent conversions. One was on a rugosa x xanthina seedling that has been completely sterile for me so far, unfortunately the three blooms on the promising lateral branch, didn’t set hips. The whole section of the plant subsequently died, so I’ll never know for sure. The second probable conversion is on another sterile rugosa hybrid, not one of mine. Both of the possible/probable conversions grew out from axillary buds that had been exposed to trifluralin (just painted on suspended in water) while the shoot was rapidly expanding. Usually the most tender part of the tip turns black and dies, but a little farther back the growth is just stunted. This region is where the interesting side shoots have originated. Side-shoots from farther down have all been normal in appearance.
The second possible conversion, just like the first, did not set hips on it’s first three blooms (in 2002). But I’m hoping that maybe next year, things will be different. I think that maybe I’ve gotten chimeric conversions that haven’t extended into the LII layer yet. That’s where the pollen and ovules originate, so it’s important that this tissue be doubled. I’m hoping that as the plant matures and increases in size that at some of the tetraploid cells get incorporated into the LII layer, and fertile sectors result.
Good luck with your plans. Tom
Now that I’ve been talking about it, I can’t stand to wait, so I collected two leaflets from the rugosa hybrid. I’m gonna try to do a clear nail polish imprint when I get home, and tommorrow look at them under a microscope to check stomata size. Until then, here’s a scan of the two typical leaflets from treated and untreated portions of the same plant…you be the judge…
Link: www.geocities.com/tesilvers/converted_rugosa_hybrid.html
Nice documentation! Also, really loved your glauca hybrid. The contrast looked really great.