Cattelya with bacterial brown spot?

[WaterWitchin]

Assistance, please? I have a catt separated from my others for about four months now. Found it upended behind my shelving outside this summer (darned dogs or wind). I repotted, cut off what I thought was stress-related damage, but moved to a separate area away from other orchids, just.in.case.

It was doing well, re-rooted itself into LECA, and had a new leaf coming on. Now I look, and here it goes again.

Is this pseudomonas or a salvagable issue? A part of me wants to save it, and a part of me wants to pitch it in the trash and run away screaming.



---------- Post added at 09:00 AM ---------- Previous post was at 08:56 AM ----------

PS Here's a picture of other side...



And no, the black part is not sunken, and I've not seen any blisters prior to either black spot arriving. Do note... it's in my basement under lighting, with a bunch of outside ferns, etc, I'm wintering over, and I haven't looked it over carefully for about a month. Newly discovered.

[MaisyMay]

Calcium defiency? I have 2 rescue catts with calcium defiency that had a leaf like that. Google it! I am treating it with dolomite lime and oyster shells.

[WaterWitchin]

Hmmmm, okay, I'm google-knowledged now.

I have easy access to oyster shell (have chickens) and also have calcium carbonate used for a RES turtle. Put a bit of both in... can't hurt, might help, right?

Am still anxious about telling the difference between a calcium deficiency and a bacteria/virus. Sure wish it could talk to me in a language I understood a bit better.

[Leafmite]

I'm not sure what is going on with your orchid, after looking at the pictures. When my cattleyas are calcium deficient, the affected parts are normally black. I don't think what you have is a virus, either. It looks more like a fungus infection.
Here is a link that, if I have typed it in correctly, should help:

Orchid Pests, Orchid Diseases

---------- Post added at 03:22 PM ---------- Previous post was at 03:16 PM ----------

Calcium is important, though, and the bit of black on the leaf could be a sign that you should add more. I'm not quite certain about the brown part.

[WaterWitchin]

Good link, Leafmite. Thank you. I'd seen one main page on the site, but this definitely had more details. I emailed with pics to see if there were any suggestions. Will update when I hear from them.

---------- Post added at 07:20 AM ---------- Previous post was at 07:18 AM ----------

I don't think it's calcium deficiency, as wouldn't other of my orchids have the same problem?

---------- Post added at 07:52 AM ---------- Previous post was at 07:20 AM ----------

Wow! That was quick. I am thankful and impressed with the rapid assist. Yes, it is bacterial brown spot. Was told to treat with peroxide or copper if I can. Also going to move it to a different area of the house, but still away from other orchids.

Hmmmm.... how do I treat a sick orchid with peroxide?

[NYCorchidman]

no on Ca deficiency, which shows up mostly just on new shoots as black mark and sometimes yellow halo around it.

It looks like some kind of disease, but I'm not sure.

By the way, sprays that contain copper complex are fungicides, unless it is one of those 3 in 1 product that has bactericide mixed in them.

Regarding using hydrogen peroxide, it is mainly for sealing up cut wound and surface cleaning just like its use for humans. so it would not be useful at all for this situation.

The best thing is to remove the affected leaves.
Isolate the plant away from other healthy ones.
Then keep your eyes on it.
If the symptom develops further, then you can consider using sprays. maybe 3 in 1 type just in case becayse it is not completely clear what kind of infection this is.

Good luck!

[silken]

I would say no to virus and just likely a bacterial or fungal infection. I seem to get this or similar on random leaves now and then. And I don't get water on my leaves, so that isn't the issue for me. Hydrogen peroxide would just disinfect which could help. A good fungal/bacterial spray like Physan would be a good choice IMO. You could cut any real bad spots out but if they are dry and not spreading I would be inclined to leave them unless they are easy to remove only the spot. Keep the leaves dry and give it a not too cool place to recover. It will have to grow new unblemished leaves as those spots won't go away.

[euplusia]

Six posters, six various opinions. Not uncommon.
Here you get the seventh advice. The plant looks stressed, shriveled bulbs, in the first pic to the far left side an uneven leaf surface. I guess that the repotted plant has not yet produced sufficient roots to nourish the new lead. It is stressed. In General Cattleyas have a high demand of Calcium and a bad rooted plant producing a new shoot can quickly run into a deficiency. Remember that symptoms become visible late after a long time of latent undersupply.
Than a rapid growth with weak cells makes the tissue susceptible to secundary infections. Fungus infection always indicates weakness.
I would take a razor blade and cut off the sick emerging leaf one centimeter below visible transformation.
I do not advice to cut away the old leaves, even if it is eyesore. I do not consider them to be contagious, and the plant needs the stored energy to build the new shoot and roots. Fertilization over the leaves can help to absorbe nutrients and then you need a large leaf surface.
Fungus sprays: possibly helpful.
Bacteria: I don't think so.
Edema/mesophyll cell collapse: No
Virus: Always possible, but never identifiable from leaf symptoms. To my observation black streaks, spots and rings caused by virus develop on mature leafes.

[Bud]

If that is bacteria, your plant will die in 3 days....bacteria is fast. I am with euplusia on this...it is fungi infection by looking at the yellow rings around the dark spots....the plant is fighting it....and yes calcium supplement must be given to make the plant stronger.

---------- Post added at 02:54 PM ---------- Previous post was at 02:44 PM ----------

Its cold and damp in the basement....invest in an electric heater and a small oscillating electric fan....and maintain Cattleya lighting at all times.

[WaterWitchin]

A huge thank you to all! I've cut back nasty bits, peroxide on cuts, then cinnamon, and put it on heat mat. My basement area where plants are is warm, gets "real" light plus LED supplemental, and there's a fan for air movement. Fairly high humidity.

Also added extra calcium supplement top dressing just in case. And realized the fertilizer mix I use has a calcium supp. in it... don't think it's that, because it's the only one I have that looks this way.

I'll give a progress report back on it in a month or so.

Again, thanks to all for the opinions... if I didn't want 'em, I wouldn't ask.