Hi Shashi,
I assume you are asking for this while you wait for your request on this thread Border Radius for Text Inputs - #3 by psp316r.
I will post an update on that thread specifically (just for anyone searching for this in the future), but in terms of a workaround, the best option is to make custom widgets that have the border radius you want. However, after talking more with the Tulip team, we are going to work on getting this implemented natively in our widgets, so if you can wait a little bit, you can avoid having to making custom widgets!