Hi, try to like this
1.create diffrent LOV'S as per your requirment
2.go to your item(where this lov u want attached) and create key list trigger under item level
3.write the query based on condition
create group with query creates a runtime record group while populate_group_with_query populates records in an existing group (Design time)
a recent article on record group can be found on adfarticles
Forms does not have a Built-in for dynamically creating an LOV; these objects can only be created in the Forms Builder during design time. You can, as numerous people have tried to demonstrate, change the Record Group an LOV uses dynamically. Unless you are changing the Column Mapping Properties of the LOV, using different Record Groups to supply the data for an LOV should work for you. If you need to change the Column Mapping Properties, then you will need to create multiple LOV objects with the different mapping you need and then assign the LOV to your Item dynamically.
Hope this helps,