Purple leaves

[roby]

my friend has this problem, someone can help us understand what it is?












thanks in advance

[ryrycochinco]

Looks like a bacterial/fungal infection. Cut off discolored leaves and treat plant with disinfectant such as cinnamon. If the infection continues to spread, divide the plant up into groups of three or more pseudo. Discard or allow infected divisions to die, and hopefully you'll have healthy/uninfected divisions leftover. Good Luck

[Zoi2]

The plants are just getting a LOT of light.
Joann

[zxyqu]

Yeah, you could be giving them some really high light, and the plant is responding by putting out purplish tones. But I would also monitor this carefully, as it could be a disease. My guess though is with Joann.n Reduce light, and see what happens

[roby]

unfortunately is not an excess of light, the purple color appears also attaches to the stem covered by sphagnum.
If it is a virus, the damage is enormous, greenhouse, there are about 300 plants.

[King_of_orchid_growing:)]

It is not a viral, bacterial, or fungal infection. It is an over production of anthocyanin pigments in the orchid's leaves. For some of them this coloration is normal when they're exposed to proper light levels.

Light is a complex topic of discussion. Visual light is just one aspect of light. There's also UV.

They're most likely affected by the UV portion of light.

If you wish, you can research on your own time, how light behaves, the properties of light, and how it affects plants/how plants react to light.

[BruceP]

I agree with Philip that it's anthocyanin pigmentation. This is normal and healthy for C. aclandiae and schilleriana. Mine grow in very high light and the leaves are nearly black.