DataGridViewComboBoxCell selection issue

            dgvSalaryUS.RowCount = dgvSalaryUS.RowCount + 1;
            dgvSalaryUS.Rows[0].Cells["ColNo"].Value = 1;


            DataTable dtCity = new DataTable();
            dtCity.Clear();
            dtCity.Columns.Add("CityID",typeof(int));
            dtCity.Columns.Add("City", typeof(string));
            DataRow drCity = dtCity.NewRow();
            drCity["CityID"] = "1"; drCity["City"] = "A"; dtCity.Rows.Add(drCity);
            drCity = dtCity.NewRow();
            drCity["CityID"] = "2"; drCity["City"] = "B"; dtCity.Rows.Add(drCity);
            drCity = dtCity.NewRow();
            drCity["CityID"] = "3"; drCity["City"] = "C"; dtCity.Rows.Add(drCity);
            drCity = dtCity.NewRow();
            drCity["CityID"] = "4"; drCity["City"] = "D"; dtCity.Rows.Add(drCity);
            drCity = dtCity.NewRow();
            drCity["CityID"] = "5"; drCity["City"] = "E"; dtCity.Rows.Add(drCity);
            DataGridViewComboBoxCell SalaryComboBoxCell = new DataGridViewComboBoxCell();
            SalaryComboBoxCell.DataSource = dtCity;
            SalaryComboBoxCell.ValueMember = "CityID";
            SalaryComboBoxCell.DisplayMember = "City";

            SalaryComboBoxCell.ReadOnly = false;
            dgvSalaryUS.Rows[0].Cells["colPlace"].ReadOnly = false;
            dgvSalaryUS.Rows[0].Cells["colPlace"] = SalaryComboBoxCell;
            SalaryComboBoxCell.Selected = true;

            dgvSalaryUS.Rows[0].Cells["colPlace"].Value = 3;

I want to assign  dgvSalaryUS.Rows[0].Cells["colPlace"].Value = 3 but it displaying 3  ...please help me to solve this issue

saju