Join Records in Linq one column?

I want the output like

Test Genre1/
Test Genre2/
Test Genre3/Test genre1               //(Bcoz id 1 as Test Genre1)
Test Genre4/Test genre2               //(Bcoz id 2 as Test Genre2)
Test genre1/Test Test genre3/Genre5   //(Bcoz id 3 as Test Genre3)

It should be combination of the id and parent id in Linq.

Any help will be appreciated...