What disease will this be?
 

Today cut this pseudobulb of a cattleya, which about nine months ago began to get this color and slowly rising from the rhizome upwards. In the center it was green but the tissue that covered it was dead as you can see. The plant is in good condition and finished its flowering so I decided to cut this bulb that was in the center of it. Apply daconil in the cut, I suspect the fungus Rhizoctenia S. I would like to hear your advice.

Has anyone gone through this? Those who cultivate for years, have nothing to say? I would appreciate your advice.

That looks like it could be sunburn. Nine months would be a very slow fungus.

Hard to tell for sure with that pic but it could be nothing more than normal aging. When catts get big enough, the oldest growths do eventually die back. It's typically a slow process and the plants seem to absorb those older growths...the leaves, as well as the pbulbs, will gradually dry up and turn to sticks. Some will only lose the leaves and you're left with leafless pbulbs.

This can also happen after major root loss. Example - after a rough dividing of a large plant. In this case, the orchid truly does "eat" the older growths in order to provide energy to make new ones.

Next time...a pic of the whole plant before you remove anything would be better for diagnosing whatever is going on. It's too hard to know for sure with one partially shriveled growth.

Thanks to everyone for the advice, I did not put the photo of the plant because it is healthy but I was curious to know if this was a fungus The two opinions fit the plant well, the climate here is very strong and always take some sun in the morning. Greetings.