<dxg:GridColumn FieldName="name_col" Header="Наименование кафедры"  Name="col">
                    <dxg:GridColumn.CellTemplate>
                        <DataTemplate>
                            <dxe:ComboBoxEdit Name="ComboBox" DisplayMember="name" PopupMaxHeight="150" 
                                              IsTextEditable="False" ItemsSource="{Binding ElementName=rb_kafDomainDataSource, Path=Data}"/>
                        </DataTemplate>
                    </dxg:GridColumn.CellTemplate>
                </dxg:GridColumn>

 <navigation:Page.Resources >
        <DataTemplate x:Key="comboboxEditor">
            <dxe:ComboBoxEdit Name="Kaf_ComboBox" DisplayMember="name" PopupMaxHeight="150" 
                              IsTextEditable="False" ItemsSource="{Binding ElementName=rb_kafDomainDataSource, Path=Data}">
            </dxe:ComboBoxEdit>
        </DataTemplate>
    </navigation:Page.Resources>
........................

 <dxg:GridColumn FieldName="name" Name="Kaf"
                                CellTemplate="{StaticResource comboboxEditor}">
 </dxg:GridColumn>

  LoadOperation<z_main_block_proc_Result> loadz_main_block_proc = MainContext.Load(
                    MainContext.Getz_main_block_procQuery(OpenPlan.str_block,
                    OpenPlan.ID_work, OpenPlan.ID_year,
                    OpenPlan.ID_spec, OpenPlan.ID_user));