Dear Vaibhav,
Thank you for your reply. I have understood the procedure of transporting the hierarchies and their categories. Rewarded you as helpful answer.
As per the information suggested by you, it says that "The report can only be executed for a given hierarchy once. If a hierarchy already exists in the target system, the hierarchy will not be re-transported".
In my scenario, the hierarchy (R3PRODSTYP) is already available in target system (test system) so this hierarchy and their categories will not be retransported. So what i am thinking is, i want to transport the 'comm_category' table values from dev to test. Is this a good idea or will there be any issues raised after doing so? If this is a good approach, transporting of 'comm_category' table is enough or do i have to transport any other table values also?
Please guide me. 
Regards,
Maddy.