Orchids Exposed to Radiation

[Mahon]

So I thought I might like to see what everyone's opinions are on this project I will be starting...

Here is the project: Study the effects of Gamma radiation (from a Cs-137 source, with the decay product Ba-137m producing Gamma) upon a selected orchid taxon. One orchid plant will be irradiated, the other grown normally. The beta minus decay of Cesium-137 will result in gamma emmision from the decay product Barium-137m.

Of course, I am still developing my hypothesis and need to do some "pre-testing" tests, to see how much a plant can take without the effects of lethal ionization or too much irradiation that will completely stop meiosis of cells. I don't think that the beta particles are of high concern on the project. but if it is, perhaps I will use 3mm thick aluminum shielding, allowing only the gamma rays to reach the plant.

Overall, this experiment is meant to study the effects of radiation resulting in mutation, and possibly adaptation as a final result. As soon as I can come up with more "pre-tests", the explanation still remains vague.

So, with this said, any ideas, suggestions, thoughts, comments, references, or ridicule? Thank you all for your time...

-P.A. Mahon

 

[gore42]

Pat,

I think that it would be much more interesting to test the effects of that same radiation on protocorns or seed. Once the plants are full grown, about the best you can hope for is tumors... I doubt that the effects would be significant enough to affect entire blooms.

However, if you have mutations or other radiation related damage in the seed or protocorns, they will be passed on to all of the cells that grow from them, and you could get much more dramatic effects. Just a thought.

- Matt

edit: You also might want to consider some more serious shielding than aluminum... something with a bit more density Maybe the aluminum is perfectly safe, but I'd rather be certain and use lead foil.

 

[gonewild]

oke: It's not nice to fool with Mother Nature.

I agree with Mat, better use lead foil. (I think aluminum is for protection against alien life forms.)

If you were to radiate tissue culture plants in vitro you would have something to base the effect on, maybe?

 

[Mahon]

Pat,

I think that it would be much more interesting to test the effects of that same radiation on protocorns or seed. Once the plants are full grown, about the best you can hope for is tumors... I doubt that the effects would be significant enough to affect entire blooms.

However, if you have mutations or other radiation related damage in the seed or protocorns, they will be passed on to all of the cells that grow from them, and you could get much more dramatic effects. Just a thought.

- Matt

Matt,

I did consider using orchid seeds, but I wanted to see what would come of the gamma rays emmitted to mutate the DNA in the plant... basically, I was hoping for mutation of not just any cells, but the meristem cells... I think you are right, tumors would probably be a result of irradiation.

Then also, I won't be here long enough to get accurate results from seeds... if I use Florida native material, I may be lucky and see germination right before I ship out...

edit: You also might want to consider some more serious shielding than aluminum... something with a bit more density Maybe the aluminum is perfectly safe, but I'd rather be certain and use lead foil.

I am not sure yet... the beta minus produced by Cs-137, I think, wouldn't do too much to the plant, as the decay product Ba-137m would be producing the gamma rays... I will have to see how plants respond to unshielded and shielded inside the irradiator... that will definitely be a "pre-test"...

Thanks for your input, I appreciate it... I will most likely put some extra orchid seed in the irradiator, just for fun.

-Pat

 

[Mahon]

If you were to radiate tissue culture plants in vitro you would have something to base the effect on, maybe?

The problem I thought of that is the irradiation of the container in which the plants are growing in vitro... also, the tissue culture medium would be irradiated... I think irradiating the container and medium would be giving off radioactive particles, while the plants are inside (over ionization of the plants?)... perhaps irradiating the meristem tissue before it goes in vitro?

Good ideas Lance, thanks!

-Pat

 

[gore42]

Pat,

I just read that second section more carefully, and I see what you mean now about the shielding. I only glanced at that section the first time and didn't realize that you intended to use the aluminum as a filter.

Anyway, if I were you, I'd get a bunch of cheap clones of Phals to do this on, and irradiate them as the spikes are just beginning to initiate. This would acheive a couple of goals; your control group would be genetically identical, which is important... and Phals cheap and fast growing enough that you could get results pretty quickly.

- Matt

 

[gonewild]

Matt,

Then also, I won't be here long enough to get accurate results from seeds... if I use Florida native material, I may be lucky and see germination right before I ship out...

-Pat

I don't think you dare do this with native material. Think of the consequences if mutated native plants escaped your experiment. Better stick with something as Matt suggests, phals.

 

[Mahon]

Pat,

I just read that second section more carefully, and I see what you mean now about the shielding. I only glanced at that section the first time and didn't realize that you intended to use the aluminum as a filter.

Anyway, if I were you, I'd get a bunch of cheap clones of Phals to do this on, and irradiate them as the spikes are just beginning to initiate. This would acheive a couple of goals; your control group would be genetically identical, which is important... and Phals cheap and fast growing enough that you could get results pretty quickly.

- Matt

VERY GOOD IDEA! This could, at the least, be a starter project...

Thanks!

-Pat

PS: Yeah, I did mean the aluminum as a filter (better term for it)... 15 seconds of exposure to Cs-137 is a lethal dose, and Gamma travels through aluminum like its nothing, so I would be dead...

 

[Mahon]

I don't think you dare do this with native material. Think of the consequences if mutated native plants escaped your experiment. Better stick with something as Matt suggests, phals.

You're right... if they do grow and survive when I am gone, a single waif could have some bad effects to the species in nature...

-Pat

 

[gonewild]

You're right... if they do grow and survive when I am gone, a single waif could have some bad effects to the species in nature...

-Pat

Remember the Killer Bee, it happens.

 

[Drorchid]

I know they use radiaton in small doses when breeding for new colors in Poinsettia's. First through traditional breeding methods (by making a cross, and selecting the most vigorous plants with the nicest bracts) they select some good potential plants. They clone these plants, and by putting them under radiation you get color sports (mutations that either make white, pink or mottled bracts). So they come up with a whole new series of Poinsettia's but just differ in the color of the bracts.

It would be interesting to do radiation on a proven mericlone of say a Cattleya or a Phalaenopsis to see if you would get any color sports as well.

Robert

 

[ScottMcC]

How exactly are you planning on quantifying how much radiation you deliver? Have you planned how many Gray will be delivered to the plant? And furthermore, how will you ensure that it is delivered evenly to the whole plant? Or are you going to "gamma knife" them?

You should really talk to a radiation oncologist before you undertake this project--I'm sure they'll have a lot to teach you about radiation that will simplify your life.

 

[littlefrog]

I think just doing it would simplify his life considerably... Or at least shorten it. This is not an experiment for amateurs. If you were doing this in a university setting you would need substantial training and proof of such, or the university could be in serious (I mean hundreds of thousands if not millions of dollars) trouble. I don't know where you would get access to the radiation sources outside of a hospital or research university. If you do have access to such a source outside of these venues, I'm sure the FBI and NRC would really like to talk to you...

However if you insist on doing it, and have the proper training, I suggest you should treat protocorms. Even if you could get a stable mutation in a meristem of an adult plant, how would you propagate it? Cloning paphs is not really going to work... Treating a few thousand protocorms would give you a far better chance of seeing a mutation at the doses of radiation you would be using (sub lethal). Remember that most of the mutations (I'd wager 99%) you get will be silent, in non coding DNA (of which there is a whole lot), or introns. Even if you do hit a gene, there is no guarantee that you will actually change the protein enough (or at all) to see a phenotype. If you actually do change a protein, chances are good that you still wouldn't see a phenotype... In the real world, you would need to screen tens of thousands of plants to have any real chance of seeing something interesting. This is probably about the number of poinsettias you have to screen to see something interesting in the system that Drorchid suggests.

 

[ScottMcC]

there you go letting science get in the way of a good opinion again Rob...

actually Rob, I totally agree with you. Mahon, I think your idea is interesting, but I'm pretty certain you're in over your head, and working with radiation is something that shouldn't be dabbled with.

I still think you should talk to a radiation oncologist--you have much to learn about physics and physiology before you should be turned loose with the gamma rays.

 

[Heather]

In addition to the comments of Rob and Scott, I was wondering who is funding your research, Pat?

 

[bwester]

I'm wondering who in their right mind would give you anything even mildly radioactive.

 

[Mahon]

I think just doing it would simplify his life considerably... Or at least shorten it. This is not an experiment for amateurs. If you were doing this in a university setting you would need substantial training and proof of such, or the university could be in serious (I mean hundreds of thousands if not millions of dollars) trouble. I don't know where you would get access to the radiation sources outside of a hospital or research university. If you do have access to such a source outside of these venues, I'm sure the FBI and NRC would really like to talk to you...

However if you insist on doing it, and have the proper training, I suggest you should treat protocorms. Even if you could get a stable mutation in a meristem of an adult plant, how would you propagate it? Cloning paphs is not really going to work... Treating a few thousand protocorms would give you a far better chance of seeing a mutation at the doses of radiation you would be using (sub lethal). Remember that most of the mutations (I'd wager 99%) you get will be silent, in non coding DNA (of which there is a whole lot), or introns. Even if you do hit a gene, there is no guarantee that you will actually change the protein enough (or at all) to see a phenotype. If you actually do change a protein, chances are good that you still wouldn't see a phenotype... In the real world, you would need to screen tens of thousands of plants to have any real chance of seeing something interesting. This is probably about the number of poinsettias you have to screen to see something interesting in the system that Drorchid suggests.

My school has a Model B Gammator for irradiation. The source is a Cesium-137 rod, which is about down in the 250 Currie range. In order for myself to recieve significant radiation, I would have to comletely destroy the shielding material, or somehow break the irradiator. In a sense, this IS for amateurs, even for those who don't know what they are doing. There are definitely some things you do not want to place into the irradiator, but nothing I would be doing would pertain to that.

As I explained earlier, I do not have enough time to expose radiation upon seeds, protocroms, explants, etc... right now, I am only focused upon plants. Maybe I will try something else much later.

No, I do seriously doubt the chances of gamma rays hitting DNA... instead, I would be relying upon the water being distributed to the cells to distribute the radiation. Any ideas?

I'm wondering who in their right mind would give you anything even mildly radioactive.

What about an Alpha source? Pretty hard to actually recieve radiation from it, unless you injest it or get it caught inside your body... open sources are quite dangerous, the irradiator is a closed source with thick lead shielding and a safety door.

Thanks all for suggestions and comments. I believe I will get a few Phal. mericlones this weekend, and start tests on Monday.

-Pat

 

[ScottMcC]

so...seriously. how many gray are you delivering, what pattern, and what kind of effect do you expect?

talk to someone who knows a lot about radiation. I know very little, and I know that. that's why I let people who know about it do it, and stay away from it myself.

 

[PHRAG]

Be careful Mahon, we already know what gamma radiation can do when used improperly...

 

[aquacorps]

What are you going to use as a phantom?