Brown patch on the undersurface of leaf

[iceicebaby]

Hi, The under surface of my phal leaves develop brownish slat gray to black patches that are shiny in nature the leav looks shriveled at that spot.
From the top the leaf looks yellow. The plants growth is slowed down.

Please help

regards,

Dev

[Eyebabe]

Looks like a pseudomonas infection...which can cause crown rot.
Sure it could be some other less common phal infection but removing the leaf was the best thing to do