Virus Testing

[isurus79]

I tested a few of my plants for virus and got a bit of a surprise in my first try! Anyone else do a virus test and get surprising results?

https://youtu.be/2ApD18Lwiew

[Toadwally]

Originally Posted by isurus79

I tested a few of my plants for virus and got a bit of a surprise in my first try! Anyone else do a virus test and get surprising results?

https://youtu.be/2ApD18Lwiew

Yep. Seemingly flawless plants tesring positive, and other plants withs suspicious symptoms test negatively repeatedly. I'm testing only for the two main viruses.

[Roberta]

Originally Posted by Toadwally

Yep. Seemingly flawless plants tesring positive, and other plants withs suspicious symptoms test negatively repeatedly. I'm testing only for the two main viruses.

Same here. I generally don't test unless there is something suspicious about a plant - failure to thrive, concerning patterns on leaves, color break on flowers (especially on Catts) I have not found a lot of virus problems - growing outside with lots of air circulation around plants and few bug problems helps. But there are some... Of course the classic is Ctt. Porcia 'Cannizaro' ... plant is vigorous, no color break on flowers, but this cultivar has been known to be virused for years. (The original FCC was virused, and it has manifested itself in the mericlones taken from that.) I grow it in an area well away from the rest of my collection. And, along with producing copious blooms in the fall, is very handy for testing my test kits. I use the Rega kits from Taiwan, which don't need refrigeration and have an 18-month shelf life (Agdia is 12 months, and because of the way they are packaged, that's pretty accurate) . But I don't use them all that fast, so it's good to know if a past-expiration strip is still good. There's the test line for sure. But beyond that, just to be sure, I test a sample of the plant now and then. And I have found that those Rega Agitest test strips are good even 2-3 years past expiration. (Yup, plant is still virused...) The difference is that the individual strips are in sealed packages - moisture is the enemy of the tests, and the Agdia strips are packaged with multiple strips in a little tube. So once open, there is air exposure that can't be avoided.

[Bayard]

Yes, after seeing color break in a Cattleya intermedia it tested positive for one of the viruses. I started doing some more testing and found some of my treasured plants tested positive as well. All got trashed.

[katsucats]

Except for several (out of laziness), I've tested every single plant that comes into the house, and I've gotten in my opinion an unacceptable rate of virused plants from vendors everyone else think are A+. The vast majority of virused plants have no symptoms, at least for a while. Some suspect plants are surprisingly virus free. If I only tested ugly plants, I would have missed most of the virused ones.

I've actually gotten tired of buying test strips and tossing plants that I'm now only buying flasks and plants from select vendors that I haven't gotten viruses from. In my experience, that's a handful out of dozens. I hate to be like chicken little sounding the alarm. I've seen members in this forum buy plants from the same batch (even mericloned ones) and vendor that I tested positive from, showing off how healthy their plants looked, and I couldn't do anything but cringe. It's gotten a bit stressful, so my solution is that I simply stop buying plants from the majority of vendors. Not even exaggerating. I'm afraid of going to orchid shows from the PTSD of seeing those test strips and the fact that I know most people don't test.

[isurus79]

Originally Posted by Toadwally

Yep. Seemingly flawless plants tesring positive, and other plants withs suspicious symptoms test negatively repeatedly. I'm testing only for the two main viruses.

Sounds about right! I'm tossing mine that test positive.

Originally Posted by Bayard

Yes, after seeing color break in a Cattleya intermedia it tested positive for one of the viruses. I started doing some more testing and found some of my treasured plants tested positive as well. All got trashed.

Ugh, that must have been really frustrating! I'm just getting started on my virus testing journey and I hope I don't lose too many plants.

Originally Posted by Roberta

Same here. I generally don't test unless there is something suspicious about a plant - failure to thrive, concerning patterns on leaves, color break on flowers (especially on Catts) I have not found a lot of virus problems - growing outside with lots of air circulation around plants and few bug problems helps. But there are some... Of course the classic is Ctt. Porcia 'Cannizaro' ... plant is vigorous, no color break on flowers, but this cultivar has been known to be virused for years. (The original FCC was virused, and it has manifested itself in the mericlones taken from that.) I grow it in an area well away from the rest of my collection. And, along with producing copious blooms in the fall, is very handy for testing my test kits. I use the Rega kits from Taiwan, which don't need refrigeration and have an 18-month shelf life (Agdia is 12 months, and because of the way they are packaged, that's pretty accurate) . But I don't use them all that fast, so it's good to know if a past-expiration strip is still good. There's the test line for sure. But beyond that, just to be sure, I test a sample of the plant now and then. And I have found that those Rega Agitest test strips are good even 2-3 years past expiration. (Yup, plant is still virused...) The difference is that the individual strips are in sealed packages - moisture is the enemy of the tests, and the Agdia strips are packaged with multiple strips in a little tube. So once open, there is air exposure that can't be avoided.

I got the tests from Taiwan as well. I wish they were cheaper!

Originally Posted by katsucats

Except for several (out of laziness), I've tested every single plant that comes into the house, and I've gotten in my opinion an unacceptable rate of virused plants from vendors everyone else think are A+. The vast majority of virused plants have no symptoms, at least for a while. Some suspect plants are surprisingly virus free. If I only tested ugly plants, I would have missed most of the virused ones.

I've actually gotten tired of buying test strips and tossing plants that I'm now only buying flasks and plants from select vendors that I haven't gotten viruses from. In my experience, that's a handful out of dozens. I hate to be like chicken little sounding the alarm. I've seen members in this forum buy plants from the same batch (even mericloned ones) and vendor that I tested positive from, showing off how healthy their plants looked, and I couldn't do anything but cringe. It's gotten a bit stressful, so my solution is that I simply stop buying plants from the majority of vendors. Not even exaggerating. I'm afraid of going to orchid shows from the PTSD of seeing those test strips and the fact that I know most people don't test.

Yikes! I hope my favorite vendors aren't on that list!

[Roberta]

Originally Posted by isurus79

I got the tests from Taiwan as well. I wish they were cheaper!


(

A way to get the best possible price from Rega is to put together a group order from your society or maybe more than one. I got mine as part of a group order which was big enough to max out the price break.

If you find that most of the plants you test are clean, you can "gamble" a little by combining bits of up to 5 plants. (so that you end up with the amount of material that you'd use for 1 test... don't overload the test or you may get false positives) The tests are very sensitive so reducing sample size will still work. Of course, if you test 5 in one test and you get a positive, you have to go back and test the individuals. So it depends on whether or not you have a significant number of positives. And keep one of those positives around (isolated) to QC your test strips after they expire... they stay good for a long time but you need to check now and then.

[isurus79]

Originally Posted by Roberta

A way to get the best possible price from Rega is to put together a group order from your society or maybe more than one. I got mine as part of a group order which was big enough to max out the price break.

If you find that most of the plants you test are clean, you can "gamble" a little by combining bits of up to 5 plants. (so that you end up with the amount of material that you'd use for 1 test... don't overload the test or you may get false positives) The tests are very sensitive so reducing sample size will still work. Of course, if you test 5 in one test and you get a positive, you have to go back and test the individuals. So it depends on whether or not you have a significant number of positives. And keep one of those positives around (isolated) to QC your test strips after they expire... they stay good for a long time but you need to check now and then.

Luckily, I got mine in a group order.

[katsucats]

Originally Posted by isurus79

Yikes! I hope my favorite vendors aren't on that list!

I've seen some of your YouTube videos. It seems you're a huge Catasetum fan as I am. Here's a little interesting story for what it's worth.

I bought a Clowesia dodsoniana once on eBay, from... (I forgot his name) we'll call him Bill, from NY. I asked him where the plant was sourced, he said wild collected, then we started a little conversation about his collection that he was planning to sell divisions of, and where to source some Catasetum species. The dodsoniana wasn't virused, thankfully, but I told him I was skeptical of buying it due to another vendor where dodsoniana's are sold, so his response of it being "wild collected" assuaged my fears.

So I relayed to him an experience I had with a well known Catasetum vendor where every Catasetum that I got from them except one (out of like 5) were virused. Hint: It's not SVO. To be fair, the vendor promptly refunded me after testing his own parent stock and confirmed the viruses, but that doesn't inspire much confidence for the rest of his plants. So Bill tells me, surely enough, he had also bought numerous plants from said vendor, and that he'd test some of those plants later on.

Two days later, I get a message on eBay, and Bill tells me his plans have changed, since he couldn't in good conscience sell virused divisions. So yep, the plants he had tested from said vendor were also virused.

I'm not going to go as far to say that there are some systemic issues going on, but statistically speaking, there probably is. In any case, buyer beware.

[isurus79]

Originally Posted by katsucats

I've seen some of your YouTube videos. It seems you're a huge Catasetum fan as I am. Here's a little interesting story for what it's worth.

I bought a Clowesia dodsoniana once on eBay, from... (I forgot his name) we'll call him Bill, from NY. I asked him where the plant was sourced, he said wild collected, then we started a little conversation about his collection that he was planning to sell divisions of, and where to source some Catasetum species.

Then, I relayed to him an experience I had with a well known Catasetum vendor where every Catasetum that I got from them except one (out of like 5) were virused. Hint: It's not SVO. To be fair, the vendor promptly refunded me after testing his own parent stock and confirmed the viruses, but that doesn't inspire much confidence for the rest of his plants. So Bill tells me, surely enough, he had also bought numerous plants from said vendor, and that he'd test some of those plants later on.

Two days later, I get a message on eBay, and Bill tells me his plans have changed, since he couldn't in good conscience sell virused divisions. So yep, the plants he had tested from said vendor were also virused.

I'm not going to go as far to say that there are some systemic issues going on, but statistically speaking, there probably is. In any case, buyer beware.

I plan to test my plants from the vendor you bought from that had the virused Catasetums when they start growing again. I really fear for my Cyrtopodiums, which I’ve purchased from that same vendor more frequently than the Catasetums.