Hello Latha,
the problem is that the ":ITAB" variable is not accessible within the dynamic sql statement. You can store the values from :ITAB in a local tempoary table which you can use then in the dynamic sql.
But from my point of view I would avoid the dynamic sql and would use a public synonym. The public synonym would point to the table (in the different schemas on the different systems). Within your SQLScript you could code agains the public synoym w/o the dynamic sql part.
Regards, Florian