Hi amit,
The way you are accessing the dictionary objects in action2 is not correct because you hav created one instance in action 1 and try to access it on action2 which is out of scope.Do try to add the disctionary object declaration in a vbs file and then attached it to QTP interface or call it at run time and then then try to access it in your QTP test/actions. eg
'declare this on VBS file
set Obj=createobject("scripting.Dictionary")
Obj.add "A", "Apple"
'QTP expert View
'Action1
msgbox obj.item("A")'Print value-"Apple"
Obj.add "B", "Banana"
'Action2
msgbox Obj.item("B") ' print value -"Banana"
Hope that this make some sense for you

regards
Niranjan