Hi Amarnath,
you can style the InsertionCell and use a DataTrigger that will set the ReadOnly property to True for the desired fieldname.
For example:
<Style TargetType="xcdg:InsertionCell">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=FieldName,RelativeSource={RelativeSource Self}}"
Value="OrderID">
<Setter Property="ReadOnly"
Value="True"/>
</DataTrigger>
</Style.Triggers>
</Style>
Xceed - Software Developer and Technical Support