phal infestation needs your help

[Phyrex]

Hi all. I know I've been away for a while but I had to seek help with this sickness that has attacked and keeps on attacking my phals. Any advise would be appreciated as I have tried many things but nothing seems to help.

PS the third picture is of the second leaf on the plant that was attacked after I'd removed the first infested leaf.

PPS the infected area starts with a discoloration, then an indentation and then browning.

[Phyrex]

Here's a keiki of the same equestris from before that has the same thing

[Phyrex]

Here's some other good examples of the disease.

[TwoStems]

I'm not really an expert yet but, my first instinct is sunburn...how bright is the light where you keep them?

[Phyrex]

I'm sure it's not sunburn as some plant have it some don't. Only phals have it, no other genera. I've been trying to segregate the sick ones but I'm not sure how far the disease will travel. They're still in the same room just on a different wall.

[Brutal_Dreamer]

Richard I wonder if you might have spider mites on that phal? At first it looked like cell collapse from cold, but the additional photos make me think perhaps an insect is sucking the leaves dry. To test, take a damp, white paper towel and wipe the underside of the leaf. If you see a slight discoloration or orange-ish color come off on the white towel, you have spider mites. To treat, use rubbing alcohol and clean each leaf. Increase the humidity around these phals and the mites will not come back. This is just a best guess. Hope it helps. AND - nice to see you.

Cheers,
BD

[Phyrex]

Hi Bruce. I've tried that too. No coloration. I'm down to Mesophyll Cell Collapse or false spider mites in my research unless I get something else testable.

[walingwaling]

hmmm, looks like something is chewing their...

[Brutal_Dreamer]

Hi Bruce. I've tried that too. No coloration. I'm down to Mesophyll Cell Collapse or false spider mites in my research unless I get something else testable.

Richard,
The more I look at this, the more I am convinced it is spider mites. Maybe they are just a different color than the ones I have see that are orangish?? In any event, treat with a pesticide (regular mix level) and increase humditiy. Make sure to re-treat with a pesticide in 7 days and in 14 days again. If the humidity level around your plant is 30% increase to 60%. I hope this helps!!

Cheers,
BD

[opaline]

Hi I agree with Bruce you definetly have spider mite invasion. Sometimes the white paper towel trick gives a false positive and vice versa, depending on temperature maturity and extent of population. Paper towel might just show colouration similar to that of dirt/ dust. On thinner leaves you would see a fine stippling on the upper surface but phals leaves are thick and your photos demonstrate how a phal shows mite damage. Treat all your plants. Spider mite does have worldwide resistance to many pesticide products so rotate your treatments and try and obtain a miticide.