Auto Comment ?

[GigFlint]

When you are uploading, check the twitter, facebook, and Google+ boxes and type in a comment. When it's finished and published, it'll leave that message on those respective platforms.

I want the comment to be on youtube on the video which i uploaded

What these two say. That's the only way, there's no automatic way to do it

 

[mycharliequinn]

sorry,
it's not one of the upload defaults you can set.