DIY Virus Checker?

[articuno75]

Agdia’s Easy-to-Use, On-Site ImmunoStrip Identifies Hard-to-Detect Cymbidium Mosaic and Odontoglossum Ringspot Viruses in Orchids Has anyone seen this, used it, or know about it? If you have used it, how well does it work. Looks cool and might be handy to have on hand,,, if reliable.

[tizzycat]

Jenny I never heard of this but agree it would be handy to have around. Interesting.

[Cynthia, Prescott, AZ]

I took a close look at it, and don't think it is all that great. The price for a 5 test kit is too high all together, $12 each test. The 25 test kit comes out to $4.80 each test. But this is a single test that does not give the added info on which virus is present, CMV or ORSV. Now I don't think it is all that important to know which virus your plant has, but for similar cost, $5.25 with 21 or more samples being tested ($6 for single sample), you get more reliability, and a breakdown on virus type. I also note that they say the strips last 1 year in the frig., so 25 tests are still going to have to be used up in one year. Course there is the postage one way for your 21 samples sent out, about $5.

Still, I am thinking of ordering the 25 sample kit just to see how well it works.

[Brassavola]

It looks very useful... I thought that two of my orchids were infected by a virus, so I've done some research about viral infections and have learned that, when visible, viral diseases form a some kind of regular or symmetrical patter on foliage. It's just important to isolate the plant as soon as possible, to be careful about disinfecting the tools, that orchids are not too close to each other and to be careful about flying pests. I know this is sometimes not as easy as it sounds...
Here are some pages that contain photos of orchids and plants infected by viruses:

Orchid Virus

Virus Diseases

Symptoms of virus diseases in plants

[JLu]

I think there is some value, but it is limited as Cynthia said.

Since I have a lot of species Catts and many of them were 100% infected during the corsage and cut flower days of the 40's, 50's and 60's, I am concerned. I already threw away a great C. labiata that was obviously virused based on flower color breaks. Makes me interested in having a test available. Some of these species sell for astronomical amounts (many in the $200 to $1000 and more range). It certainly would be nice to get a quick test result for a few dollars that might save that much money.

[FLaCo]

You guys have given me something to worry about. All this virus talk is making me a hypochondriac.

[Brassavola]

Me too. I have to tell myself aloud every morning "Don't worry.Everything is alright."

[JLu]

Ya'll don't need to panic over viruses. They are not new and for the most part few people ever see the results (even when they have it). You do need to establish clear, consistent practices to avoid the transfer of sap from one plant to another. That means sterilizing tools faithfully. It also means not transferring sap on your hands when repotting several plants at the same time or removing spent blooms. You stand a much better chance of getting a virused plant when you buy a Hosta at a nursery than when you buy an orchid. Viruses don't jump off a plant and run through your collection. Sap has to be transferred, but the chance of infection when sap is transferred is very high.

I mentioned earlier that large flowered Cattleyas that were part of the corsage and cut flower trade are highly infected. This information via reliable references written by authors who were part of the industry or reporting based on sources in that industry. See. AA Chadwick, et al, The Classic Cattleyas or Courtney Hackney, American Cattleyas. However, many cultivated orchids are now infected and infected plants can have a virus and not show signs for years or maybe not at all. It is said that Paphs either don't get viruses or never show signs...I do not know.

This post will result in numerous suggestions as to how to sterilize tools. I think I've seen them all and nobody can prove whether their method works or not...including me and people who know way more than me. There are the simple suggestions like soaking in alcohol, Physan 20, or trisodium phosphate (which will quickly corrode metal tools ending that problem for sure). Then there is the "ultimate" solution of heating your tools in an oven to more 350 F for 1 hour or heating them with a torch. Heating my hands hurts too much so I rely on soap and water.

I am completely unwilling to rely on the three chemical baths. Some will say they work...but how in Hades do they know? We have a pathogen which might not show any signs or very delayed signs..so considerable virus testing would be required and for many viruses there is no simple test and no known minimum level of detection.

Personally, I heat my tools with a propane torch until there are very,very hot sometimes glowing red. Will it work...don't know, but it makes me feel good. I buy stainless steel scissors at the dollar store for, guess what, a dollar...which I'm sure will soon be $2 given the value of the US dollar. I've heated some of them more than 20 times and they look like hell, but they still work so I figure 5 cents per cut isn't too bad.

Do not panic over viruses, if you plan to grow plants you will encounter them. Use some common sense in keeping things clean and wish a lot that it doesn't happen to you or that it's minor if it does. Look at pictures so you will recognize a virus if you see one. Remember, they are not curable..get rid of an infected plant or if it's value is too great, isolate it. By the way, viruses are not spread by pollen so an infected plant can be used for breeding. In my mind, the pod parent might yield virused seedlings, but many people say they do not and that all seeds are safe. I just do not know. Maybe somebody else does know for sure.

PS...one thing I forgot. Some will say that mericloning will eliminate viruses. Well...they only read the first sentence. The meristem (or growing tip) of a plant can grow faster than the virus spreads. So if someone sets out to mericlone virus free plants, they can attempt to get clean meristem tissue which apparently can be done at least in some experimental cases. However, tissue culture labs that are propagating plants for retail are not trying to eliminate virus, just make clones. They produce virused batches of clones. So, tissue culture is both a method of cleaning plants and a method of spreading viruses...the latter far out numbers the former. Go to a retail nursery and look at the Hostas right now (in the spring for you Aussies). You'll find entire batches of seedlings that show virus signs.

[Jerry Delaney]

I agree with JLu about depending upon chemicals to "sterilize" your cutting instruments. For a chemical to "kill" virus is dependent upon just too many variables. Not only is the concentration of the agent used important but time, temperature, amount of organic material present along with numerous other things enter into the efficiency of chemical sterilizers. JLu is using a much surer method by heating the instruments. One just needs to insure that a sterilizing temperature has been reached. I always say that if you heat an instrument to the point it glows red, any virus present that lives deserves to propagate its self. I personally use single edged razor blades that I get for ~3 cents each at Harbor Freight and wear disposable gloves that I buy for $1.00/100 at the dollar store and use new ones for each orchid.
The cut flower trade did a lot to get virus spread around albeit unintentional. I can remember Hauserman's discarding thousands of plants used for the cut flower market because they were virused.
JLu, I have been told that virus can be transferred with the pollen, but just like some people claim that some insects can transfer orchid virus, I have never seen any definite, controlled experiment to prove that fact one way or the other. Supposedly, if you have a valuable plant that is virused that you want to use for a stud plant, if you use it as the pod parent you don't have to worry about transferring virus to other plants. Also, if you let the pod go to maturity and sow dry seed, there is very little chance of the seedlings being virused. Conversely, if you green pod, the chances of virused seedlings is much greater.
You are certainly correct in stating that mericloning does NOT necessarily eliminate virus.
As far as the test strips, I have no idea how sensitive the elisa type tests are now. I do know that years ago when I was working as an industrial microbiologist, the sensitivity level was very low. Maybe these marketed to day are very accurate for all I know. However, years ago if one submitted leaf tissue for a virus test and it came back positive, the next year tissue from the same plant might test negative. As you pointed out, there is no cure so the plant did not suddenly become "virus free". It was most likely due to virus not being present in sufficient quantity for the test to detect it.
Perhaps, most of all, when you purchase a new orchid just remember that your mother was right. You don't really know where it has been!!!!

[JLu]

Thanks for the reply Jerry. Interesting that you heard exactly the opposite than I about the transmission of virus by pollen or pod parent. I wonder what the right answer is or whether anyone really knows. Sometimes I am amazed about how little we know about stuff on this planet. BTW, the Am Hosta Society is sponsoring research on how best to sterilize tools, I believe at the U of Minn but not certain (haven't paid my 08 dues). AOS looks for ways to help hobbyists and assisting (financially) this type research would certainly be beneficial.

I forgot one point I wanted to make in my original virus post. It is true that most of you will never have a virus and even fewer will know it if they do. No question that viruses will stress a plant preventing it from exhibiting its optimum performance. As to whether it will actually kill a plant, maybe, maybe not, but in any case it will be loooong process of decline. If you plan a long involvement in orchid growing, it is best that you not infect your whole collection upfront because you might find it necessary to start over in the future. If this is a passing fancy (and sadly it is for most), I wouldn't sweat it.

One little trick that is often talked about here is using a wooden skewer to test moisture in a planting mix. While I think its use is unnecessary, I stipulate that it does work. Consider that you are very likely to nick a root with the skewer and then nicking a root of another plant can transmit a virus. It seems to me that it would be best to buy a bushel basket of them and use them once or assign one to each single plant. Again, all this is to prevent a low probability, but highly destructive event. As Cynthia often points out in technical language, risk is a mixture of how high the probability of occurrence and how severe the results. This certainly falls in the low risk, high severity category. Depends on your risk tolerance, just like the stock market does.

[Jerry Delaney]

I agree JLu. I have heard and read all kinds of ideas and theories about orchid viruses and as you said, who really knows if many of them are right or wrong. It's like I use to tell my managers that while everyone has an opinion about a certain thing, that does not make you right or wrong, it just makes you opinionated. When it comes to orchids and orchid viruses I try to be cautious. While under the best conditions one will oft times shoot your self in the foot, that doesn't mean that one should take aim before pulling the trigger.

[FLaCo]

I hope it doesn't happen. I mean how do these big nurseries keep everything "virus free"?