Valore di default combobox in un datagridview

dt = new DataTable("OpenOrders");

                dt.Columns.Add("Campo1", typeof(string));
                dt.Columns.Add("Campo2", typeof(string));
                dt.Columns.Add("disney", typeof(string));

                row = dt.NewRow();

                row["Campo1"] = "1";
                row["Campo2"] = "2";
                row["disney"] = "Nocciola";

                dt.Rows.Add(row);

                row = dt.NewRow();

                row["Campo1"] = "11";
                row["Campo2"] = "22";
                row["disney"] = "Paperino";

                dt.Rows.Add(row);

                dv = new DataView(dt);

                kDataGridView.DataSource = dv;

                defaultValue = new ArrayList();
                for (int i = 0; i < kDataGridView.Rows.Count; i++)
                {
                    defaultValue.Add(kDataGridView.Rows[i].Cells["disney"].Value);
                }
                kDataGridView.Columns["disney"].Visible = false;

                disney = new DataGridViewComboBoxColumn();

                disney.Name = "disneyUffa";

                cell = new DataGridViewComboBoxCell();
                cell.Items.AddRange(
                new string[] { "Pippo", "Paperino", "Minni", "Nocciola" });
                cell.ReadOnly = false;
                //cell.Style.NullValue = "ae";

                disney.CellTemplate = cell;
                kDataGridView.Columns.Add(disney);

                for (int i = 0; i < defaultValue.Count -1; i++)
                {
                    kDataGridView.Rows[i].Cells["disneyUffa"].Style.NullValue = defaultValue[i];
                    kDataGridView.Rows[i].Cells["disneyUffa"].Value = defaultValue[i];
                    int lol = kDataGridView.Columns["disneyUffa"].Index;
                    kDataGridView.UpdateCellValue(lol, i);
                    kDataGridView.Update();
                    MessageBox.Show(kDataGridView.Rows[i].Cells["disneyUffa"].Value.ToString());
                }