Leaf Issue : virus? / bacterium? / fungus? / ???

[Lars Kurth]

Hi,

I bought 4 plants at the BOGA congress a few weeks back and had all of them in quarantine so far (in my terrarium). Anyway, I was out on business for 4 days, when I got back the leaves of an Annelisia (formerly Miltonia) candida I bought had extremely bad spotting and became yellow.

There are no spots on the bulbs, only the leaves. When I left for the US, the leaves were pristine. The speed of impact does indicate something bacterial or environmental. The brown spots are sunken into the leaf tissue and tissue is yellowing from around those sunken spots. Some of the yellow/brown tissue on the leaves was glassy/and slightly watery, which could be an indication it is something bacterial. But it certainly does not look like Erwinia.

I checked http://www.staugorchidsociety.org/cultu ... seases.htm, and nothing quite fits. I supposse the sunkenness could imply Pseudomonas, it does not look like Erwinia. None of the leaf spots illnesses fit.

I cut all th eleaves off, but am worried. Note that these are all leaves off the fresh growth. Also note that none of the pseudobilbs from previous years had any leaves, indicating that maybe this issue is not new on this plant.

I am certainly not overwatering - watering every 7-10 days and the pot dries within 2 days or so in the terrarium. Also, there are no signs of spider mites or similar.

Lars

[Connie Star]

It looks to me like photos I have seen of ring spot virus. I'm no expert though.

[Leafmite]

I have not seen anything like this. I can see why you are concerned. If you can have it tested, that might be a good idea.

[Lars Kurth]

Well, what I was told is that

It looks like a fungal disease similar to septoria which can can be caused by wetness on the leaves and poor air circulation. It's a matter of removing the infected leaves and spraying, possibly more than once. Never a good sight once it sets in.

So I sprayed with Phyton 35.

[Stray59]

Boy - I would hit it with everything I have! It may be fungal or bacterial, but it also has many traits of viral. I am not a disease expert, but the fact that this showed up after the stress of bringing it back from a trip - well that is such an old viral trick! A little stress can allow a virus to overwhelm an otherwise healthy looking plant.
I would test the leaves with a test strip to be sure.
It sure is unsightly! Keep us posted on what you find out!
Steve