This week I've had a new and interesting "case study". A Cymbidium I had tested returned a positive result for both Orchid Fleck Virus (OFV) and Odontoglossum Ringspot Virus (ORSV). This is the first time, out of the dozens of plants I have had tested, that I have ever had a result with more than one virus.
In this case the necrotic markings were different to my previous experiences with OFV and ORSV and only one leaf tip had a faint chlorotic marking that I have seen with ORSV (and I didn't see that until I got the test results and went looking for it).
Necrotic markings:
The chlorotic marking that I attribute to ORSV:
In this case the plant wasn't a valuable one (thankfully), so it has been a valuable learning experience. I haven't encountered OFV symptoms often enough to say that these necrotic markings wouldn't appear in just an OFV infection (in fact the thin leaf with the necrotic tissue near the tip does look similar to a photo I have seen), but this will be a useful reference.