Cheapest virus tests?

[MateoinLosAngeles]

Got this Miltonidium showing some signs of viral infection. It actually blooms great, but it's placed next to other Oncidiums and Zygopetalums. They all have the typical black spotting on the leaves, but its next-door neighbor has started to show some yellowing of the leaves, albeit in the oldest ones.

This one has diamond streaks with small circles, and I'm trying to decide whether to cut the sick leaves or throw it away.

If it tests positive, I would probably isolate the other Oncidium to see if there are any signs of infection spreading. If it tests negative, I'm sure this is some bacterial infection from being too hot and lacking air movement. Perhaps it is low nutrients, as I have been under-fertilizing this year.

Is there a cheaper service than agdia.com?

[Ray]

It is impossible to diagnose a viral problem without testing. I think there are but two brands available, Agdia and Regabio.

That might be an acidovorax bacterial infection…

[Roberta]

The Regabio tests are much cheaper per test (like about half) but the minimum order is 50. Their shelf life is much better than what is promised - I have had some 3 years past expiration that worked fine. Unlike Agdia tests, they also don't need refrigeration. So might be a good investment just to have around.

[MateoinLosAngeles]

Originally Posted by Roberta

The Regabio tests are much cheaper per test (like about half) but the minimum order is 50. Their shelf life is much better than what is promised - I have had some 3 years past expiration that worked fine. Unlike Agdia tests, they also don't need refrigeration. So might be a good investment just to have around.

Based on their websites, Agdia is $75 for 5 tests and Regabio is $200 for 50... $15 vs. $4 per test. I think we got a clear winner haha

Is this Taiwan website the only way to buy them? Or is there a US seller? Access Denied

---------- Post added at 03:28 PM ---------- Previous post was at 03:22 PM ----------

Originally Posted by Ray

It is impossible to diagnose a viral problem without testing. I think there are but two brands available, Agdia and Regabio.

That might be an acidovorax bacterial infection…

While I wait for the virus test strips to arrive, my plan is to treat it as if it were a bacterial infection, perhaps more likely than fungal. However, the shape of the lesions and the lack of a watery blister before it got these dry streaks, made me think virus testing might be warranted.

[Roberta]

There is no US seller. Order from the Taiwan website. (Yes, it's fine... there have been several large society orders, that I was able to join, with no problems at all)

---------- Post added at 03:31 PM ---------- Previous post was at 03:30 PM ----------

Test whenever there is suspicion (another reason to just have some on hand). You totally can't tell by looking. Along with a clear price advantage, shelf life is also huge. Agdia packages the test strips in a tube. Once you open it, air (and moisture) get in and it's downhill even in the 'fridge. I have had them go bad (no QC line) in a year or less. So potentially even more expensive. The Rega strips are in individual sealed packages, so they are protected from air and moisture. They can sit on the shelf and still give a valid test several years after the expiration date which is already 18 months from manufacture instead of 12 months for Agdia.

[MateoinLosAngeles]

Originally Posted by Roberta

Test whenever there is suspicion (another reason to just have some on hand). You totally can't tell by looking.

I might need to learn a bit more before taking a big stance on my collection's virus policy. So far, I prefer to not know since some plants might be able to last a lifetime asymptomatic, based on the many divisions of historic plants that exist and are known to be virused, yet aren't destroyed because of their blooming quality...

For now, I think I will use testing on plants that I believe are so symptomatic that could be thrown away (like this one). If it tests negative, however, I would treat the infection. So the test is more to prevent me from wasting my time treating.

Whenever I'm going to repot or handle a plant I keep a 90% alcohol spray bottle next to me, constantly clean and disinfect the working area, tools, I also clean any debris from the tools with soap and water and use a torch on them. Sometimes a Physan mixture. Plastic pots get soaked in bleach overnight before being reused. Terracotta pots (and even wooden baskets) get soaked in a citric acid solution overnight and debris is removed, the terracotta pots then go in the oven at 400 for 2h.

So I think I'm doing what I can do to keep things hygienic. However, can't be perfect. For example, I don't strictly leave a disinfecting solution on the work station for 10 minutes between plants because it would take forever.

When it comes to plant placement, I can't have them separated enough so the leaf tips don't touch. Especially these thin leaved ones. I keep all the plants on trays with a grid (like eggcrate) to prevent water cross-contamination, but especially Cattleyas have roots that like to spread, they get on to other plants, they get on the shelf, some have even tried to climb my walls, and definitely many have roots that grow into the egg crate and are exposed to the flowing water underneath. So it is what it is. I try to use microbes on every watering and keep culture as close as possible to what they like to ensure there's an environmental balance that contains infections, but I can't monitor every plant exhaustively.

I may eat my words in years to come if I have a big loss in my collection. But for the time being, I think I will only test on plants showing significant signs or if the flower quality is subpar for whatever reason (to confirm whether it's due to culture or virus). Otherwise, I will just assume that small signs are fungal/bacterial and treat accordingly.

Do you have a strict virus policy for yourself?

[estación seca]

It's a complicated situation. Most hobbyists probably don't need to be concerned if they don't sell or trade plants, and use good hygeine practices. Of course biting insects like mealybugs, scale and aphids may spread viruses. Maintaining a completely virus free collection is an extremely expensive decision.

[Roberta]

I take the moderate approach. I also have the luxury of outdoor growing - plants are still crowded, but there is total air exchange. A person growing in a greenhouse that is pretty much airtight may have different needs. I test when I see something suspicious like color break on flowers (which can also be caused by thrips, etc) or a plant that is doing poorly. (Answers the question, do I try to rescue it because the problem is likely curable, or toss it because it isn't) Over the years, I have not had a problem with a virused plant (don't have many) infecting neighbors, I do test the neighbors if I find one. Again, in a greenhouse situation that might be much more of an issue.

[MateoinLosAngeles]

Originally Posted by Roberta

I do test the neighbors if I find one. Again, in a greenhouse situation that might be much more of an issue.

Do we have a clear knowledge of how CymMV and ORSV are spread? E.g. can they be somewhat airborne and be transferred from one plants stomata to another, are they carried in water, through plant fluids? Sounds like the most common carrier are sucking pests, which break into the plant's tissue. Yet, outdoors, where plants are subjected to many critters, from passing by spiders to actual pests, it sounds like you still have a low percentage of virused plants.

It would be helpful to know more about this, I'm thinking about the example of HIV in humans, it can only be transmitted through fluids from the sexual organs, anal mucus, blood, and breast milk. However, it is not transmitted from saliva, tears, sweat, etc. You can hug a person with HIV without risk of infection unless both people had an open wound that was in direct contact during that hug. Whereas, other viruses like HPV can be passed through extended skin to skin contact, Hepatitis C is through blood only, and the Covid-19 virus can be passed by simply sitting next to another person on the bus.

Do we know about the specifics of CymMV and ORSV? I think that would be very helpful in addressing prevention. Most articles I find online are pretty generic but don't really get into specifics, maybe I could try to find some actual scientific paper that has studied this.

[Roberta]

Not airborne. Water, maybe since it gets absormeb by roots and may also contact breaks in either roots or leaves. Actually, the #1 vector is humans. Sucking insects would reasonably be expected to transmit viruses, to what extent I don't know if it has been well measured. I know it isn't completely straightforward. One of the members of one of my societies actually experimented with a batch of seedlings (so a bunch of identical plants), and tried to infect some of them on purpose to test what might produce transmission. Over a period of several years, they still tested negative. On the other hand, legacy collections tend to have high rates of infection even though the owners really tried to follow good hygiene practices. So does age have anything to do with it? Or what other factors? I don't know what studies have been done. This same individual who did the test on the seedlings put together a "visual" test of multiple photos, showed it to a number of very experienced and knowledgeable people (judges, people with a botanical background, etc) to see if they could tell the virused ones from the clean ones. Nobody did better than chance, some did worse. Conclusion, appearance is an unreliable indicator.