If you want a row in edit mode to be selected you need to do the selection manually. You could try using client side selection:
masterTable = $find(
dataItem = masterTable.get_dataItems();
You could call this function on OnBlur event on the controls which are in edit mode (for example : on the last control on the row). Then you could get the row index in which the control are placed and get the row via masterTable.get_dataItems[rowIndex];
Another option to set item as selected is on the server, by setting its Selected property to true.
Additionally, if you could elaborate on your scenario and on what exactly you are trying to achieve, you could try providing a proper resolution for your case.
I hope this helps.
the Telerik team