Why is there still a white background even though a transparent png image is used? I have a very simple node set up as below for a leaf texture which is a transparent backgrounded png file. When I use the transparent shader with alpha node, I still get the white backround appearing as below, I can't figure out what's the problem here, please help.

Render view



nodes



PNG file 

Blender file

thanks a lot

Ps. I went through questions already asked here for this subject, they didn't solve my problem, even though it's a very simple node set-up - sorry if it's a duplicate which I haven't seen yet
Open up the Node Editor, select the image texture node, then open the Properties Panel N and enable Use Alpha.