Interesting lighting - coming from the bottom up.
Slightly uninteresting subject - maybe if more of the banana was in the pic? Or the lighting on top was better?
I don't know if a banana is a great subject to take a 'macro' of, because you can't include the whole banana, etc.
Great idea and really different for a photo Challenge. You show good detail in your photograph, nice lighting, good focus, perhaps a little too bright on the bottom right, but overall, a really good shot.
without the stems and title this would really be abstract, might not've know what these were. weird how the brown spots have black pinpricks at their centers.