object dependency to restrict resource

Dear Experts

I want to write object dependency for PDS in APO to select particular resource when planned order generated . i have seen the option under T-code PDS_maint . how to mantain .please suggest

scenario for example :

I have 10 resources . i want to make one of X resource to be selected always when ever planned orders are generated .Pls suggest

I can do these through procurement priority . But I want do these through object dependency

Regards

Jaisree