Composition is okay but desaturating the image didn't help in this instance. For this to score highly in my estimation, I would want to see anatomically correct texture in all the fruit (i.e. knock my socks with great texture!), which implies greater DOF, very precise focus plus somewhat different lighting. These are my preferences and you may disagree.
I'm giving a lot of leeway on this because it's largely to do with artistic expression and personal taste, but for this particular challenge I think this would have been better composed if it showed one orange in its full roundness. I like the feeling of depth in this image, but the b/w is a bit perplexing -- seems like it would have really popped in color.