# Virus testing for breeding?



## Candace (Jul 1, 2007)

This question popped in my head after seeing some requests for pollen lately. Yeah, I know the chances paphs have virus are lower than other orchids, but my question is this...If you've got a valuable plant that you want to breed, do you need to get the donor pollen plant virus tested? Or rather, should you? I think I've read that pollen can carry virus, is this true? I've done some breeding, but only with my own plants and haven't gotten any uncontaminated flasks, so I'm still new at the breeding & flasking thing..


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## Rick (Jul 1, 2007)

I don't know of anyone who's done that at this time.

I thought that virus testing was done on some other material like leaves. At least the expression of virus usually shows up in the leaves. I guess you could find it anywhere in the plant, but there is a limited amount of pollen from a paph flower to send away for testing and still leave some for breeding (except for multis). I guess you can also plan this years in advance and test one year and breed with next years bloom if the plant is clean.

Oops I see that you didn't say getting the pollen tested, but the pollen parent (by whatever means/material). 

Anyway. This is not a common practice except for those who suspect their plant might have symptoms of virus infection.


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## Hien (Jul 1, 2007)

I suspect that all plants carry virus just like humans & anything else in nature.
(why should any thing be exception) unless you raise a plant from a total sealed lab environment..
What we see as virus symptom is the expression in the plants when they are stressed. other times, the virus are dormant in the plants.


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## Candace (Jul 1, 2007)

> Oops I see that you didn't say getting the pollen tested, but the pollen parent (by whatever means/material).
> 
> Anyway. This is not a common practice except for those who suspect their plant might have symptoms of virus infection.
> Edit/Delete Message



Right, I meant testing the leaves:> 

Hein, I'm talking about the common, plant industry type viruses. Some plants that have it may not show it, but are still Typhoid Marys that can and do spread it. 

I know if the mother plant is virused there are protocols like taking the seed at the green pod stage to avoid viral contamination of the seedlings. 

I'm interested to know if virus is viable in pollen. If a paph has virus, will it also show up in the pollen and thus be transferable to the mother plant? Anyone know for sure?


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## smartie2000 (Jul 1, 2007)

I would say it could be viable because viruses are not really 'living', so it will be viable far longer than the pollen will be viable, but will only be active when it gets a host.

There are areas where viruses are not present on an infected plant. These areas are how people salvage their diseased orchids in the lab I assume (mostly in orchdis that can be mericloned such as cattleyas and cymbidiums, yes it is possible to salvage valuable plants in the lab) I am also thinking that these unaffected areas are the faster growing areas too, where the virus has not spead to quickly enough.

I'm not sure if the virus will have spead into the pollen though. There can be a chance that the pollen may contain no virus but I don't know for sure. My thoughts are that the chances are slimmer though since some buds grow so fast. ...but there are viruses that cause streaks in cattleya blooms, so I'm not sure...sorry I am confusing, maybe it depends on the virus type. Has anyone done research on these subjects? I just typed some thoughts

The other question is that can the pod parent become affected from the diseased pollen.


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## Candace (Jul 1, 2007)

> The other question is that can the pod parent become affected from the diseased pollen.



Yes, that's what I'm asking.


I didn't think it was possible to "salvage" virused orchids in the lab or anywhere else. How does that work? From what I understand a virused plant is incurable and all tissue contains the virus. Hence my pollen question.


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## Roy (Jul 3, 2007)

From past information which may need clarification, I believe that pollen can carry virus but not necessarily cause the offspring to get it. Depending on the lab you have to virus check plants, most will come back stating the possibility of virus or worse. ( particularly cymbidiums )

It has been tried here to mericlone virus out of a plant but the results are that the plants left are so weak they are basically useless to grow.


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## littlefrog (Jul 3, 2007)

I read somewhere, years and years ago, that seed from a virused plant was not virused. In other words, the interior ovary is a 'privileged site' so to speak, that virus cannot or does not enter. If you harvest such seed dry, then you have little chance of the seedlings being virused. If you harvest green, then you can contaminate the seed with the green tissue from the mother plant. Spooky.

I think pollen is probably not a good source of virus. All of this could be wrong or superseded by current research, of course. I think testing your stud plants is probably a really good idea, but if you do mostly dry seed flasking it really shouldn't be a problem for breeding. Assuming you segregate your seedlings from your virused stud plants, of course.


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## Candace (Jul 4, 2007)

I haven't been able to find that much about orchid pollen and virus. Most articles state what you've written that two virused cymbidiums, example, can produce unvirused progeny. 

It seems other plants that have "normal" plant pollen can and do carry virus in the pollen. It's spread by bees and biting insects. The biting insects bite a hole and the wind blows the pollen on the leaf (from a virused plant) and viola!


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## smartie2000 (Jul 4, 2007)

Candace said:


> I didn't think it was possible to "salvage" virused orchids in the lab or anywhere else. How does that work? From what I understand a virused plant is incurable and all tissue contains the virus. Hence my pollen question.



I don't remember where I read about salvaging virused plants so I don't know the exact process. I remember it cost a lot and is only used on valuable plants. I'm sure it is only available for plants that can be cloned though and they find unaffected tissue and use it to create a new plant.


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## Ernie (Jul 4, 2007)

I recently got an e-mail from Agdia about a new "dipstick" method of virus detection. Looks much like aquarium water chemistry dipsticks for pH, ammonia, nitrite, hardeness, nitrate... Anybody else hear of this? See...
www.agdia.com

-Ernie


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## Candace (Jul 4, 2007)

Yes, I've read all about it. Very expensive, much more expensive than the (last I heard) $4 per testing Critter Creek Labs does. The only application I could see this would be worth the money for, is to carry to shows, auctions etc. in case there's a very expensive orchid that you want to virus test on the spot. Otherwise, I'd still go with Critter Creek Lab if you can wait a couple of days for the results. My opinion only.


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