why not just use the DataSource to bind the data in your case the data source is the RSS ? and set AutoGenerateColumns to rue , something like that :
List<string> names = new List<string>();
names.Add(" the alghabban ");
GridView newGrid = new GridView();
newGrid.DataSource = names;
newGrid.DataBind();
and when you need to add row just add it to names and bind the Grid view again