请帮忙看下我编的数据库备份语句有什么错误?

procedure TDataForm.BitBtn1Click(Sender: TObject);
var
  FName,SQLStr:string;
begin
  if opendialog1.Execute then
    begin      FName:= OpenDialog1.FileName;
      ADOQuery1.Close;
      ADOQuery1.SQL.Clear;
      SQLStr:= 'buckup database agv to disk=''' + FName + '''';
      ADOQuery1.SQL.Add(SQLStr);
      ADOQuery1.ExecSQL;
      application.MessageBox('备份成功','提示',MB_OK);
    end;
end;