Virus tragedy - What should I do?

[turock]

After receiving a few plants that seemed suspicious, I bit the bullet and bought some virus test kits.

Well, the suspicious plants were clear. But a large portion of my collection is virused. Most of the plants that are infected were total surprises. They're growing vigorously and show none of the classic symptoms. Others had absolutely no symptoms, except for being lethargic growers. Tragically, most of my favorite plants are virused.

What are your opinions / practices when it comes to dealing with virused plants and protecting your collection? I know some of you are not as concerned with viruses as others. What is your reasoning?

Also, most of the virused plants I own are ones I purchased from my local orchid society. I want to support my society at raffles, shows, and the like, but I want to avoid these problems in the future. What would you guys do?

[fishmom]

Last May, Janet Lamborn from Agdia (they make the test strips) came and talked to our Diablo View Orchid Society. She was a very good presenter. Here is a portion of the summary of her talk:

"If you are old enough to read this,
then chances are you are virused. Ninety
percent of us currently carry the herpes
simplex virus in our bodies and yet are
unaware of it presence. Ever had a
wart? This is the human papilloma virus.
Shingles? It is caused by the varicella
zoster virus. So the next time you test
your orchid for a virus and it comes back
positive, you may want to look in the mirror
before you decide to get rid of the plant."

Basically, she suggested that with good hygiene you can enjoy virused orchids for many years. She discussed how to prevent transfer of the viruses, how to test, and symptoms.

If you would like to read the entire summary, here is a link to the society website:
Newsletter

Click on the June newsletter, which will contain a summary of the presentation.

[Leafmite]

I don't test orchids but I do keep them away from my other plants. In the past, the entire virus thing got me quite upset...now, though, I do the best I can to protect my collection and try to observe my orchids so I can, hopefully, spot problems before they spread. My orchids don't get perfect care so I figure that if they are infected, they will likely be affected by the virus soon enough rather than continue looking good.

So far, i have only had two orchids that have expressed virus symptoms...one was a new orchid that was still in isolation and the other was an orchid that I brought home from a meeting and put into isolation as someone had jammed their orchid into it on the show table and caused some damage (and I didn't like how the flowers and leaves of that orchid looked).

For those orchids you really love that express no symptoms and grow vigorously, you should test them a second time or send the leaves to a lab...just to make certain that you aren't getting a false positive.

I try to protect my collection by being careful where I buy my orchids and then keeping new orchids apart from the older orchids. If I get an orchid from another source (the OS holiday free orchid), I keep it far away from all my plants for a few months until I feel satisfied. This doesn't completely ascertain my collection will stay clean but this is my attempt.

If any of your OS members use tobacco products, be aware that Tobacco mosaic virus is easily spread and isn't as easy to kill as some of the other viruses. If the member doesn't wash their hands very well after handing the tobacco product and before touching plants, they can spread the virus to their plants. Indeed, this is why some vendors and growers that allow visitors to their greenhouses cringe when people touch their plants.

I would find other ways to support your Orchid Society. If you know the society is a source of orchid virus...cross them off your list as a source of orchids. At the shows, buy only from reliable vendors.

Sorry about your orchids. That orchid I had to toss that was infected at the meeting was one of my favorites and I haven't been able to replace it (an older hybrid). I have also lost many orchids some years ago with a plague of Calcium deficiency and, last year, I lost a bunch due to baking them under the lights (and not watering enough). It is really tough. Remember, though, that after you have cleaned out your collection, bleached your grow space, and determined that your remaining orchids are free of virus, you will have the space and opportunity to try something new.

[turock]

Thanks for the insight. I will read the article.

What can I expect from my virused orchids? Will they all eventually display symptoms and die from the virus? Or can they live indefinitely in the proper conditions?

[Leafmite]

If you take very good care of them, many of them will live indefinitely. Many orchids only express symptoms when they experience stress. They will never be quite as healthy as they would have been if they were not infected but you can definitely mask many of the symptoms with good nutrition and a no-stress environment. I think most Phal-type Dendrobiums are quick to exhibit symptoms and Cattleyas often have their color-break but some of the others will show no symptoms at all if they are happy.
You will need to prevent insect vectors and practice good hygiene as to prevent spreading the virus to your healthy orchids. You should also keep the ones that are known to have a virus away from the ones that are not so that the healthy ones remain healthy. Good luck with whatever you decide!

PS. I grow other plants and it is surprising that for some types of plants, people really don't seem very concerned about virus.

[RobinDavis]

Thanks for the info.

[silken]

I tested some of my Cattleyas and was disappointed to find a number of them showing positive for CMV and ORSV which are the two viruses most orchid growers seem to dread. I tossed them all and did manage to replace several of my most precious ones. However, I only tested the ones I was suspicious of for some reason. Some of them were very good growers with clean leaves but I couldn't get them to bloom, regardless of what I did and they were definitely mature. So in a way, they were just taking bench space anyways. Others bloomed and to my dismay had the obvious colour break in the blooms. So those too, were not worth keeping around as when I go thru the trouble of getting them to bloom, I want them to look pretty and have nice photographs. The odd one, and it was very few, were the ones with ugly blotches on leaves. Any of those for the most part must have a fungal or bacterial problem or a different virus.

So it is hard to judge a plant for virus by just looking and I prefer to see blooms on it to make sure they don't have colour break. But only 1 of those 2 viruses causes the colour break. I have seen members bring their gorgeous blooming Catt to show n tell but it has colour break all thru the flowers???? Its hard to know what you are getting unless you know the grower is fairly careful about how they grow their plants and then it is still a gamble.

But I consoled myself with the fact that those I tossed, I had suspicions for one reason or another and they needed to go. That left more space for my many that tested negative.

A lot of the positive ones, were ones I have had the longest. When I first started growing, I didn't realize virus was such a big issue and would put many of my plants in a large basin and water them together to have a good soak. I am sure that is how many of them got infected. Needless to say, I do treat them all individually now and none share anything! Pots are sterilized in strong bleach water and cutting tools are sterilized between cuts as well.

The tests from Agdia are supposed to be something like 95 or 99% accurate so I believed them and didn't use a 2nd test. They do have a shelf life and should be kept in the fridge until used.

Sorry to hear of your virus tragedy, but hopefully going forward, you will have better blooming plants that are not virused.

[tucker85]

Years ago, if one of my orchids had color break, I would wait one more blooming season to see if the color break continued. It almost always did. Now if I see color break or if a plant is a poor grower, I test it. If it's positive, I throw it out, because it's already showing symptoms. I have no doubt that I have plants with virus that aren't showing any signs. That's fine with me. I sterilize my shears between plants and take other precautions not to spread any disease. I worked for many years as an RN in a hospital and as a paramedic in the street and we just assumed that every patient had a contagious virus and we acted accordingly. It's called universal precautions. I do the same with my orchids.

I was at the Cattleya Symposium in Ft. Pierce, FL last year and one of the speakers was Jeff Bradley. He's well known for his collection of historic and classic cattleyas. Many of his plants can be traced back to the early and mid 1900's. He told us that many of those orchids have viruses because they've been in collections for so many years. But he keeps them because they are often the only example of a particular orchid.

[turock]

Robin, I used the Agdia tests for Cymbidium Mosaic and Oncidium Ringspot virus.

Silken, I understand what you mean. There are some that I tossed right away. They looked ugly, flowered poorly, and grew slowly, and were easily replaceable. It was still a big step for me. I have never thrown away an orchid that wasn't 100% dead, rootless, leafless, overrun with fungus, etc.

I'm keeping the more vigorous ones around for now. Most of them are getting ready to bloom, so we'll see what those flowers look like. With space and time limitations, I can't justify keeping a plant that doesn't look its best and is easy to replace.

Fortunately, a friend of mine, who wants to learn how to care for orchids, has volunteered to take the virused ones off my hands. This way I don't have to throw away the ones that have sentimental value, and will get to "visit" them as I help my friend learn how to care for them.

[silken]

I know how you feel. I too normally don't throw out anything with the slightest bit of green. I give it my all to try and pull it thru. So some that were 15 growth specimens of health just defied going into a garbage bag. But they did, plant, pot, media and all. And I certainly don't compost their media as our compost goes into the garden and the virus could spread to my perennials. I normally re-use plastic pots after sterilizing well, but when I knew I had virus, I wasn't taking the chance.