Yes, its called Sigatoka and affects a lot of banana plants. Need to spray it with a fungicide.

It's most likely growing conditions. Don't let it be too wet or dry. What is your greenhouse temp? if the pot's sitting on the ground, put it up off the ground.

The pot is off the ground and the low temps are 50..... I had the same issue though this summer and could not get a response here other than maybe it was not humid enough. I did just spray with a fungicide to try that out but it is not Black Spot. The pictures just do not look the same. This does not get black but from yellow to brown.

That's definitely Sigatoka if I've ever seen it Tom. Google "sigatoka banana" and click on "images" and you'll see the pics are very similar. Leaf goes from yellow to brown.

Squam256 Looks like you are correct. The black spot pics I saw did not look like what I have but these pics do. Now to find an effective treatment !

Looks like the two chemicals I bought should take care of the issue. Believe it all started from an older banana which had gone undiagnosed ! Thank you!!

Looks like the two chemicals I bought should take care of the issue. Believe it all started from an older banana which had gone undiagnosed ! Thank you!!