Viruses and unconfirmed facts

[Orchid Whisperer]

Well, this won't be the first time I've asked a dumb question, but here goes. . . sorry, I'm actually going to ask more than one dumb question.

Here's the first one. I do understand that some viruses are REALLY bad actors, CMV and ORV/TMV have been mentioned (I think we would all agree that these are akin to rabies or other fatal virus diseases in animals). But if some of the other viruses are really hard to detect/symptoms not commonly observed, are these viruses really a problem (are they like having the common cold, for example)? I wouldn't hesitate to put my dog down if he had rabies, but would certainly care for him if all he had was a 'canine cold'.

Second dumb question, sort of related to the first - if I have an orchid that I have owned for 20 + years, it has never shown any sign of flower break, never shown other problems that "look viral", should I consider it to be LIKELY virus-free, but untested/unconfirmed? Or at least, doesn't have anything worse than "a cold"?

Last dumb question. We all get colds from time to time, and in general, most of us recover. If there are "lesser viruses" in orchids, do plants "recover" from them? Like cytomegalovirus in humans (50 to 80% of folks in the United States have this by the time they turn 40 years old), do some orchid viruses essentially stay dormant unless the health of the plant is compromised? Sorry, guess that is two questions.

FWIW, whenever I am dividing, re-potting, etc., I always act as if the plant that I am working with potentially "has rabies", and so did the one before it. Any tool that touches the orchid is either flame-sterilized, or chemically sterilized with a soak (not a dip) in full-strength bleach. This happens before I use the tool, and after I use the tool/before I store it. Same goes for orchid pots I reuse (terra cotta ones get both a bleach solution treatment, then prolonged oven sterilization at 500 F).

I'd love to hear some opinions!

[NYCorchidman]

Originally Posted by escualida

The good news is that there are some good sellers out there that will replace or refund your plant if you get it tested and it comes out positive, they will even reimburse you for the cost of the test. One of these sellers is Hausermann's, they sometimes resell Phals from other growers and I've gotten a few that were virused. I got them tested through Critter Creek and had them send the report directly to Hausermann's, when they got the report they refunded the cost of the virused plants plus the cost of the test for those plants.

Also, I have a LOT of cattleyas and some phals from Carter and Holmes and NONE of them have ever had a virus, so if you want to be 99.9% sure you're buying a virus-free plant, get one from them.

It is so nice of them for Hausermann to acknowledge your claim not like some people we talked about in the past , but they even paid for the testing fees? That is crazy, in a great way. I don't expect that much.

Anyhow, thank you so much for your vendor info.
I've been buy cattleyas locally and many are "suspicious" if you know what I mean.
I do have some from Kawamoto. haven't tested yet but so far, looks clean and grows and flowers fine.

I've looked at so many nice cattleya pictures of Carter and Holmes, but many are seedling size and I don't have the patience to wait forever.
Have you bought blooming sized cattleyas from them also??

---------- Post added at 03:07 PM ---------- Previous post was at 02:35 PM ----------

I would not compare virused animals and virused plants mainly because they are just so different.

Let me first start with your 20+ year old helahty looking & performing plant. What is it by the way? I'm quite curious.

You could say it is virus free, but without testing, you cannot be sure as you say. but then again, for all practical reasons, why would you worry when the plant is apparently doing so well for so long? would be my opinion especially you also mentioned that you treat your plants as if they were all virused.
That is actually what everyone should do, and that way, the transmission of viruses within one's collection may stay low if not zero.

I applaud your "clean" practice!

The two named viruses are important because they are the most common and also they happen to be the most destructive, so in the economic point of view (severity of crop damage done, flower quality and stuff), they are important while many other viruses that affect orchids are not as important.

I do not know the gritty details on how and why viruses may stay within plant tissues without causing any problem, then one day they break out as plants do not have immune systems like animals do.
There was a study that I ran across in the past regarding how certain (not all) plants may have something similar to animal immune system using a type of RNA related mechanism, but not sure all the detail and how extensive the study was. don't want to get into that story here. lol

In humans, when we get attacked, they are cleared by our immune systems. some do stay and "walks" out every now and then when our immune system is down, cold sore around the mouth is a good example that many people can relate to. Herpes simplex virus I (oral herpes) is in almost all people as early as infant (by adult kissing cute babies on the cheek), and this virus resides inside us in the nerves that control the mouth area. While many people with this virus may never experience the "breakout", many others do.

Then there is probably the most seirous of all, HIV.
I would say maybe orchids with CymMV or ORSV that do show symtoms and deteriorate severely is sort of like humans with AIDS who are taken over by the deadly virus.

Alright, enough of my rambling, lol
I think as long as virused orchids grow healthy and flower well, on the personal home grower level, it should be fine.
The real problem is that the possibility of transmission to other orchids that might not take it so well once infected with viruses.

[Orchid Whisperer]

Thanks for your answer NYC! I appreciate the detail & glad to know that I'm approaching virus control in a reasonable manner.

I have 3 cattleya alliance plants purchased in 1985, 2 from Jones & Scully, C. Orglade's Blaze and Cattlianthe Golden Wax (still have the receipt; the last one is on the receipt as C. Chocolate Drop 'Kodama' x Kauai Star bright 'VI'). The third is a Cattleya Wayndora from Cali Orchids in Barranquitas Puerto Rico. I also have a 4th, Epidendrum ciliare that was given to me in 1987 or 1988.

---------- Post added at 04:38 PM ---------- Previous post was at 04:36 PM ----------

BTW the Golden Wax is blooming now, maybe I'll post pictures this weekend.

[Leafmite]

I went ahead and asked a retired botany professor last year about viruses. I guess that with good culture and decent levels of fertilizer, you can prevent some orchids from showing symptoms for many years but that they won't usually be as vigorous as they could be without the virus. Many non-orchids and orchids will be quickly doomed once exposed to a virus, no matter what one does, and show symptoms or even die within months while others will just gradually decline. He also said that he found that stressing an orchid is actually a pretty decent way to get an orchid to show virus symptoms. A compromise with their immune system allows the virus to begin multiplying and spreading.
Lastly, there are non-orchid plants that will very quickly show virus traits and can be used to test other plants for virus.
Most non-orchid plants will show signs of virus pretty easily and within a few months unless they have been bred to be virus resistant, as many of our newer bedding and gardening plants have been. So, if you have a mixed collection of orchids and things that have not been bred to be virus resistant, virus can really decimate your other plants pretty quickly.

---------- Post added at 05:08 PM ---------- Previous post was at 05:05 PM ----------

The problem with the selling of diseased plants is that we spread the diseases to plants in agriculture and cause millions of dollars in damage to our food supply. Not good.

[euplusia]

I agree with nikkik and the speaker that viruses are not the number one risk to our plant's well beings. Fusarium and Erwinia are even worse. For those who want to go further here are 3 links

http://www.aosforum.org/pdf/Batchelor_17.pdf

http://www.crec.ifas.ufl.edu/academi...df/287-288.pdf

https://docs.google.com/viewer?a=v&q...ytSMVoTJPeHy2A

[JanS]

To add a side-question to this interesting post: I noticed in one of the answers a member tested all their orchids and 90%+ from orchids.com, i.e. Norman's Orchids, came out positive for virus. I have a few orchids from that source I bought a few years ago (first and only order) and one of them is now flowering for the second time and its (Cat.) flowers are a bit deformed just like last year. I have another orchid from another source that I suspect of being infected.

Here is my question: can orchid viruses be transferred through re-using the same water for multiple orchids? Here in Southern California this time of year I tend to save precious (free) rain water and use it to water several orchids in a plastic tub, then pour the water back in the watering can from the tub and do another 1 or 2 batches. I can't find any info on whether this would be a way to potentially spread a virus. Considering much of this thread suggest we all have at least one or two plants infected... Any ideas?

[Leafmite]

I don't know. Hope you get a definite answer on this.

[Orchid Whisperer]

Hi JanS

I have been advised not to re-use water as you have been doing, because of the POTENTIAL to spread viruses or other diseases. Emphasis on potential, because I don't know that spread of viruses has happened that way (but there is a risk).

Theory goes, root tissues could be broken (mechanical injury, bug/slug damage, etc.) before you water. If you water & two plants exchange sap from a virused to non-virused plant, you could exchange disease.

A hint for using that rain water sparingly & more safely. Collect it, filter it, store it in clean containers, then use a pump sprayer to apply it only to the potting medium. Just when it starts dripping out of the bottom of the pot, move to the next plant. You will occasionally need to soak/flush out your pots, but since you are using rain water, salt buildup should be minimal.

[escualida]

Originally Posted by NYCorchidman

It is so nice of them for Hausermann to acknowledge your claim not like some people we talked about in the past , but they even paid for the testing fees? That is crazy, in a great way. I don't expect that much.

I had used a home kit to test them and they wanted official results from Critter Creek, I asked if they would cover the cost of this re-testing if the results came out positive. They did and they gave me the refund, but I don't think they would do so unless you explicitly asked.

Originally Posted by NYCorchidman

I do have some from Kawamoto. haven't tested yet but so far, looks clean and grows and flowers fine.

I have quite a few from Kawamoto as well and they've never tested positive either. They are one of my favorite vendors as well, their plants are usually very large and healthy, and at very good prices. The only issue I've ever had with them is bugs and once some snails, but they are by no means the worst offender in this regard. There is one vendor that once sent me a live moth wrapped in the newspaper along with some bare root phals, and on a separate occasion sent a FROG wrapped up with one of their plants!

Now I clean all of my new arrivals religiously, drench them in insecticide soap, and repot them before letting them join the rest of my collection.

Originally Posted by NYCorchidman

I've looked at so many nice cattleya pictures of Carter and Holmes, but many are seedling size and I don't have the patience to wait forever.
Have you bought blooming sized cattleyas from them also??

I've bought a few blooming sized plants from them, and when my orders have been fairly large they've included blooming sized "bonus" plants with my order as well. One of my most reliable bloomers was a freebie I got from them.

[NYCorchidman]

Adriana- Thank you for the good answer.

JanS- Communal bath is no no for the reasons already mentioned by the other member.