I was talking with an orchid grower today who warned me about a problem
that orchid growers seem to be having, but don't know much about it or
what to do. It is called a microfungus and once it sets in it
eventually kills the orchid. It spreads very easily throughout a
greenhouse or collection and affects phrags, paphs, phals, and other
things. Small brown or orange lesions appear mostly on the undersides
of leaves and discoloration eventually spreads killing the leaf or
entire new growth or eventually the plant. Healthy established plants
may have the microfungus symptoms but still grow and bloom.
Apparently not much is known about this and there is no known cure.
Phyton 27 may help control it but it never seems to go away. One West
Coast commercial greenhouse operation apparently lost an entire
greenhouse orchid collection to what was attributed to this mysterious
"microfungus."

Anyone know more about this "microfungus?"

Thanks