I'm CymMV Positive

[Jerry Delaney]

Maybe one way to get an idea of how things are spread is to buy a young seedling test it, if clean put it with the known infected plants then re test it down the road . Just a thought .. Gin

It's a VERY good idea, Gin. Problem is, if false negatives occur how is one to prove that the seedling wasn't already infected when it was obtained. As we all know, having adequate and meaningful controls are the key and the hardest part of any biological experiment. Having spent ~40 years in biological research/manufacturing/qc I have only one for sure truth; "It's been repeatedly proven that when you take a biological organism and place it in a carefully controlled environment, under carefully controlled conditions, it will behave as it darned well pleases".
I heard years ago of a test run where they took a "Known" negative plant, severed the rhizome and placed a protective barrier at the severed point. Later, one of the separated leads was deliberately infected with ORSV. One year later both plants were retested and the one deliberately infected tested + and the other half that had been the same pot was still -. The idea was that there was no root transfer of the virus. I have no idea if this really happened but it sure makes a good story!

[Gin]

Interesting info . Jerry
I read some where that a plant can on occasion wall off virus from a puncture wound but sounds good . How about an out of the flask seedling would that work ?

[orchids3]

Have also read that plants can be forced to grow rapidly and the new growth can be removed and will grow without Virus - wish I had kept the reference but I didnt. So this is a for what it worth - probably very little.

[quiltingwacko]

I received the test strips yesterday, finally. I hope to get time tomorrow to use them. I did the opposite of your suggestion orchids3. Just the way it happened not intentionally. I cut all of the "diseased" parts off the two plants in question, a Vuylstekeara and an Odontioda. I don't know what they have, if anything. They now reside alone in a room with no other orchids. Carol

[Jerry Delaney]

That might be a good approach, Gin. I would make sure that the flask is a seed sowing (not a mericlone) and from a dry pod (green pod sowing can pass on virus).

[camille1585]

Originally Posted by orchids3

Have also read that plants can be forced to grow rapidly and the new growth can be removed and will grow without Virus - wish I had kept the reference but I didnt. So this is a for what it worth - probably very little.

I think that this was what was believed until fairly recently. I'm not sure (will have to look up the articles) but I think this was disproved. The only part of a plant I know of that can grow fast enough to be virus free is the meristem, and even that doesn't happen in all cases.
Do you think you could try to find were you read that?

[Florida_guy_26]

Let me just say that from what I have read that they say insect vectors COULD be a possibility for spread of the virus. Just because articles state no known insects that can transport the virus does not mean it isn't happening, it just means it has not been documented. That doesn't say much guys and on top of that, if you think about it- how do mosquitos, ticks, mites, etc. pass viruses and bacteria to un-infected hosts? Just because it is not written or documented does not mean it does not happen. I myself think anything that can bite or penetrate any part of the plant can carry and transfer a virus. Also, how can any one of you explain that a virus got passed to a plant after the tools had been soaked in straight bleach for 10 mins???? 15 minutes in a dilute amount will kill any pathogen on tools and surfaces unless you all have some other explanation to how it was passed. I think this kind of explanation coming from people who have the problem shows that the virus must be passed by some other means if the plant has been left alone and tools were sterilized prior to any work with the plant. Think about it- by your belief that insects are not the cause of spread in plants would be just like saying that ticks and mosquitos do not spread any harmful viruses or bacteria.... can anyone say rocky mountain spotted fever or lyme disease????

[Jerry Delaney]

Think about it- by your belief that insects are not the cause of spread in plants would be just like saying that ticks and mosquitos do not spread any harmful viruses or bacteria.... can anyone say rocky mountain spotted fever or lyme disease????

I probably should go back and read all of the posts before submitting this one Florida Guy, but if my diminishing memory serves me right, I don't know that anyone stated that insects could not transmit disease to plants. I think the statement was that there was NO KNOWN insect vector for CymMV. There is a huge difference between these two statements. For example, with all the publicity over the past few years, I can't believe there is little doubt as to the ability of mosquitoes to transfer West Nile virus from bird to human and/or human to human. Indeed there exists a whole group of viruses termed Arbovirus (arthopod borne virus) that can be spread by insects.
In retrospect, have you ever heard of a proved case of HIV being passed from one human to another by an insect? How about measles, mumps, chicken pox and any number of other viruses? All of these viruses go through a viremic phase but I have yet to hear of a confirmed case of insect transmission.
I imagine everyone is aware that the bacteria responsible for the plague can be transmitted via flea bite. But, how about tuberculoses, undulant fever. To my limited knowledge, there are no insect vectors for those diseases.
Chemical sterilization has a lot of "ifs" associated with it. I tend to agree that 15 minutes in straight bleach should take care of most things, including virus. However, there are a lot of other factors that influence any type of chemical sterilization. Strength of the sterilization agent, exposure time, amount of extraneous organic material, temperature, surface tension, and many other things come into play. That is the reason that I prefer to use heat. I have always said that "any organism that survives after the cutting instrument glows a dull red deserves to propagate itself"!
I imagine that some of the human transfer of virus could be as innocent as simply touching a flower or inflorescence and doing the same to another plant without washing your hands or changing gloves. Or, perhaps two leaves rubbing together in the wind or fan turbulence. Maybe having water drip or splash from one plant to another.
Anyway, Florida Guy, I guess anything is possible, however, some are rather improbable. I can't quite remember how it goes exactly or who wrote it, but
"Dogs have fleas upon their backs, put there for to bite um; and those fleas have lesser fleas and so on infinitum".

[camille1585]

Yes, I agree, it's stated that there is no known insect vector. Nothing rules out the existence of one. But I think (and this is just my opinion here) that it is safe to say that if there is a vector, it's not going to be one of the very common greenhouse pests (thrips, aphids, mites, mealies...) Seeing the importance of these viruses, I'm thinking that scientists have already studied all of these insects as possible vectors before arriving to their conclusions.
It may be that there is an insect vector in whatever part of the world the virus originated, where ever that might be.

[Ray]

As far as I'm aware, there are no plant antivirals, so once infected, they'll be so forever.