White Spots on Sick Phalaenopsis

[PlantGrower]

Dear Orchid Fanciers:
Can anyone identify the, "white spot disease," and suggest treatment approaches if any?
I'm a newbee (3 yr.s) to orchids and two of my hybrid Phalaenopsis are in dire straights. It's sad as they both rebloomed nicely in the spring for me.
I have posted pics of the sicker of the two. Sick plants are relocated to a friend's (plantless) apt. to hopefully spare the rest of my collection. I would like to treat these if possible and perhaps do some prevention treatment to the rest of my plants.





Thanks for Help,

[nutgirl]

Welcome to OB,

Do the spots appear on healthy leaves first or after they start to go bad?

Maureen

[Masdyman]

It could be too much light through the blinds when the sun has hit the plant at a particular angle .

[Eyebabe]

I'm at a loss here...white bumps make me think scale.
Have you picked at or cut into one of those "bumps"?

[PlantGrower]

Thanks for input thusfar. I've been out of state and just got back to internet access.
1. Light was not a factor in development of the white spots as the plants originally were at my apt. in wall mounted holders where they got little, if any, direct light. The posted pic was done at my friend's where I quarantined the two sick plants.
2. The bumps tend to occur at the beginning of a leaf's decline in health. As they spread, the leaf gets sicker looking until it drops off, as did the one I placed in a baggy to isolate the, "white bump disease."
3. I will go over to my friend's tomorrow to try a scraping of one of the bumps.
I will report back tomorrow.
Thanks,
PlantGrower (Though now I feel like the plant killer.)

[Junebug]

How long has it been since you repotted or checked your roots? The potting medium appears to be mostly sphagnum and looks very moist. Those spots could be fungal spores from too much moisture.

[RJSquirrel]

the plant got oedema from too much water and not enough light... odema is a corky, wart-like growth. so when you see the bumps the cell walls have ruptured and in an advanced stage...dont want to hurt ya feelings but that plant is just about Done 4

example
you may read further here
https://edis.ifas.ufl.edu/pp164

[Izzie]

Originally Posted by RJSquirrel

the plant got oedema from too much water and not enough light... odema is a corky, wart-like growth. so when you see the bumps the cell walls have ruptured and in an advanced stage...dont want to hurt ya feelings but that plant is just about Done 4

example
you may read further here
https://edis.ifas.ufl.edu/pp164

That's possible, I'm not sure I'd agree 100% though. I'm waiting to hear what the spots are like when they're poked/prodded.

[King_of_orchid_growing:)]

White spots are fungus.

The plant tissues had died and the fungus started growing on the dead portions of the leaf.

The watery leaf suggests edema due to over watering.

The moss may be retaining too much moisture and the pot may be too large for the root mass. If the pot is able to fit the root mass comfortably without much room at all, that should be perfect.

You may want to pull the plant out of the pot and check the roots.