Can we make the cell invisible in gridview?

Hi all,

How can i make the cell value(which is a textbox) in a gridview invisible? i have attached the file please see it and tell me what can be done..

For the add new row button the code is as below

  DataSet DSLoadMaster = new DataSet();

            DSLoadMaster = cb.DSLoad("city", "city_master");//obj.LoadDataSet("Select * from city_master");
            // Here we'll add a blank row to the returned DataTable
            DataTable DT = DSLoadMaster.Tables[0];
            DataRow DR = DT.NewRow();
            DT.Rows.InsertAt(DR, 0);
            //Creating the first row of GridView to be Editable
            GVDetails.EditIndex = 0;
            GVDetails.DataSource = DT;
            GVDetails.DataBind();
            ((LinkButton)GVDetails.Rows[0].Cells[0].Controls[0]).Text = "Insert";