James, maybe I'm just not seeing it in your photos, but when I do my virus tests using Agdia kits and I mash the leaf, the fluid in the pouch is quite green in color. Yours appears to be fairly clear. Maybe they have changed the kits over the past few months?

When one of my better-loved orchids tests positive for virus, I will usually retest it. Very rarely does it turn out differently, but there is always hope.

Some were greenish some were pretty clear. This was the first time I've done this so maybe I wasn't crushing them enough. The instructions said to rub the pouch gently so I didn't push very hard. The samples that were positive changed right away, the one both viruses in a under a minute. I did have to retest 3 because the control line didn't change so I guess those weren't mashed up enough. I assume if the control line changed there was enough in solution to get a reading.

I did order more tests, 2 of the 6 I want to retest because they seem healthy and never had any flower distortion, the rest do show symptoms so I wont retest those. I was told that false positives were possible but a false negative was very unlikely.

James

CJ they haven't changed the test - you do need to turn the test liquid green.

James I'm sorry for your results but you are wise to test. Use a blunt object to run back and forth over the leaf. The plastic material holding the liquid is very strong. We use the end of the felt tip marker we used to label the bag. Use a new razor blade for each sample so you don't cross contaminate.

Brooke

I did use a wooden spoon to rub the pouch and most of them did turn green. I did use a different razor with each plant. I used a tweezers to pick up the samples which I soaked in 50/50 bleach solution and heated with a torch between samples. I also had a bucket with 10 to 1 bleach solution for my hands and hand sanitizer just in case.

I tried to use sections that had the most spotting so maybe there wasn't much chlorophyll in the samples? The thing I don't understand is if there wasn't enough plant material in solution woukd it still show a result on the test strip?

I ordered most tests so I think I will redo a few to be sure.

James

Yes it would produce the virus red lines because it was very virused. One of mine turned the first line red before I even got the timer set :>(

Brooke

Yes, Brooke, the plastic packaging is very tough. I pop the cut leaf in, take the kit out to the concrete garage floor, and pound it to death with the back end of a medium-sized screwdriver. Lots of green.

I've done a couple hundred of these tests and have only found one negative to later retest positive, but the two tests were about 18 months apart so the virus may have been very weak or nonexistant the first time.

Call called them today to ask about the tests I did.

I misunderstood the instructions, when they say to rub gently with something like a Sharpie, I was thinking flat like a rolling pin. They explained to use the point like you were coloring and make circles from the center working to the edge.

They said the sample didn't need to be completely destroyed, the fiber just needs to be crushed. Not to agitate the bag to much because the solution will get foamy and effect the results. Also if the solution is to pulpy with plant material it can cause a false positive.

I explained how I did the test and they thought my results should be accurate, although the control line would still show even if there was no plant material in the bag at all. The control line just confirms the strip is working.

I'm going to try to test all of my plants and then spot check in the future. Thank you for the input guys.

James

I had a situation similar to yours last year. I had some older plants showing questionable symptoms so I bought a test kit. Out of the 25 tests 5 plants tested positve. Two of them were duplicate divisions so, you might say only 3 plants.
Like you I was surprised by some of the results. Some plants with symptoms and poor growth tested negative and some with few or no symtoms tested positive. Unlike you, however, I found that is was my newer plants that tested positive and not the older ones I was sure I had spread infections to before I knew the take precautions. Though I do remind myself that the test only checks for two viruses. So, my older plants could still be infected, just with a diferent virus.
I think the tests are a great tool to screen with and I know I'll buy another kit in the future to test again.