Could you please answer this question 

You can but then selenium cannot be used it it
You will have to use some other tool for desktop app

what tools can I use with cucumber using BDD concept for Desktop application?

which tools can I use with cucumber using BDD concept for Desktop application?
Do we have any open source tools which can be collabrated with cucumber for desktop applications?

There is no good tool as such which is open src for windows app

I actually find your answers very funny. 
My question is : I need to know a tool which can be collaborated with Cucumber for desktop applications. 

It it can be commercial tool too. 

any opinion

Cucumber is a framework. Its not a tool. Its a framework available in different languages.
So you need to have a tool available in any of the languages which can be integrated with cucumber.
Now - Finding any tool which uses a programming to test a desktop application  is impossible
QTP is one tool but it uses vb and that even its an IDE
. Cucumber is not available in vb

Thanks Ashish for your response.
Can I use Winium which is selenium based windows automation tool?

https://github.com/2gis/Winium.Desktop

Not sure how promising it is!

There are many such tools and they have defects as well
So please be careful

Thanks Ashish, that resolves my question.