missing texture!

I’ll be thankful if anyone help me to solve my problem:

I’d made a human character in 3 parts:- head, body & legs, hands
I’d textured it separately and saved 3 separate png files for each part
but before going to rigging, I tried to combine these three parts with cntrl+ J (in cycles), but I found that the texture related to the last selected piece alone is seen rendered!
I don’t know why…
please do help me
I’m also attaching an image of my character

this image is rendered in cycles, before joining the three pieces…

Don’t Join them. Why do you need to? But if you need to you can assign the materials to the appropriate faces in edit mode by selecting only those faces, selecting the material, and clicking assign. With any luck the UVs (you have unwrapped them of course) will still be intact. Otherwise, unwrap again.