Spots and discoloration on a Neofinetia

[camille1585]

I started seeing these symptoms on one of my Neos a couple months ago. It started on one leaf and seemed like it wasn't spreading, and it's spread to half the plant. This is only a plain standard variant, but I like it because the flowers are far larger than those of my 10 other Neos.
Any ideas what it is and if there's anything I can do? This one is kept on a separate shelf from the other due to space issues, but I'm also starting to see marks on 2 of those plants too...

[AnonYMouse]

I've never seen anything like it (dark areas, light areas and spots). Can a couple of different things be going on? Can you describe how it starts/progresses?

You know the usual routine (visual check, disinfect, isolate). You know good handling practices so I don't think this is a virus spreading (and other reasons but you never can tell-often asymptomatic in good culture).

Mayhap the collective minds here have seen and combatted this.

[camille1585]

I’ve added some photos from late February that I forgot I took. The disease progression since then was a lot faster than I thought. It started in December with that badly affected small leaf near the base of the plant and a few spots on other leaves. I had sprayed it with a rubbing alcohol and ground cinnamon mix, hoping it was fungal and easily treatable...

Like you say, I know the best practices and apply them as much as possible. Some things are still out of my control, like the mealy bugs I’ve been fighting for years. While they have caused me other problems, I don’t think it’s linked. Here’s my reasoning why:

• Mealy bug infestation caused pitting and discoloration on my Phals. Different than what’s on the Neo, but symptoms can also manifest differently on different sorts of plants.
• Last year I had leaves of 6 symptomatic plants tested for 7 viruses that occur most frequently in orchids. All tests came back negative.
• I did a major mealy bug treatment last summer (4 applications of systemic a week apart). Mealies seemed gone, all Phals grew new leaves that are still blemish free, further indicating that the symptoms weren’t due to a virus.
• Mealies have returned since January…
• It’s entirely possible that the Neo’s symptoms are related, but mealy bugs don’t like Neos, I’ve never seen a single one on them.

The conclusion of that story is that I’m thoroughly stumped.

[Selmo]

Hard to tell exactly what you have. Need a little more info. Back in December, when you first noticed this what where temperatures, light and humidity like? Looking at the tips of the leaves and the concentric circles, I would guess it could be anthracnose. Not real common but is always out there. Happens in warm, high humidity and low light conditions. Lot of times it causes leaf curl, burnt tips of leafs and premature leaf drop, along with concentric circles that remind me of age rings on fish scales or trees. The mealybugs could of been the vector that started the infection.
If this has taken 4+ months to get here, then is probably, gone thought it’s life cycle or is very slow moving and will not kill your entire plant. I would watch your other plants to make sure that they do not become infected also. Do the, increase air movement, increase the light, decrease the time leaves are wet, and good sanitation thing, and that should remedy the problem. If you want to use chemicals to treat this and other problems, then a preventative fungicide program can be used, just remember to not use the same chemical more than three times in a row, and use ones with different modes of action.
Once again, this is only a guess from a picture.

[camille1585]

Conditions were no different from other winters. 17-20C, 35-50% humidity. South facing window, but it got less light than my others Neos, which have supplemental LED light all winter. It may be a south facing window, but winters in the Netherlands are very cloudy and the days are short. I keep the Neos on the dry side in the winter.

Chemical treatment is not really an option, they are no longer sold here. I can only buy 'natural' pesticides. I'd have to see if I can get something online instead.

[Nexogen]

It is difficult to get a correct diagnosis. Sometimes, because of the too high price, give up those plants. As this plant looks, I think you should think of a nematode infection or spider mite. At the same time you can think of a mineral deficiency. Probably Abamectin (Avid) and trace minerals is indicated.
PS: It's just an opinion.