Thank you so much for the acorn tips everyone! Very kind after I arrived with such bad news! I was so surprised to find that when I checked in today!
Joshua, I had very much the same sinking feeling you seem to be conveying, and the same concern that control may not be possible or practical if growing many varieties. The silver lining may be that if you grow mainly iris, perhaps it is less important, since so many seem to tolerate viruses well? I'm a general perennial gardener, just throwing a few iris in with the rest of the lot, so for anything I add to the garden, I must to mind the effects on my other plants. (It does give me a lot of appreciation for the complexities of functional ecosystems!)
I tested mine with potyvirus Immunostrips from Agdia, which aren't cheap, but are a good deal less than $45 per test, about $50 for 5 tests here. There's a similar product from the European company Creative Diagnostics. Perhaps one or the other is available in Australia? I also tested for tomato spotted wilt and cucumber mosaic, which are also known to infect iris. And I tested for tobacco ringspot and tomato ringspot, because I had other reasons to believe those were present in the garden. They were negative for everything else. I didn't test every plant for everything, of course! The expense gets to be very high very quickly!
In the future, I think I may try biological testing as a cheap alternative. There are certain plants that are susceptible to very nearly every virus--quinoa is one of them, and some varieties of tobacco. You can inoculate these plants and see if they develop symptoms. It's quite slow, of course, as you have to grow a small plant and then let it develop a disease, but for things that I've had in the garden for a long time, I am not in a rush. For many viruses, the symptoms of infection will be the same, but it is not always important to determine exactly which virus. For me, the outcome is mostly going to be the same no matter what: no mercy! So I think I might get a few hundred quinoa seedlings going in the house and just systematically, obsessively check everything in the yard.
I honestly can't believe there are people who don't know what to do with themselves when they retire! I live for the day!
I also came to understand that the lists of viruses that infect a particular type of plant are not at all comprehensive, sadly.
And it's quite hard to find this information! I'm a medical librarian, so I was quite astonished it wasn't all organized in an up-to-date database like so much similar biomedical information. That's the difference in funding right there.
