SPField authorField=list.Fields.Cast<SPField>().FirstOrDefault(n => n.Title == "Кем создано"); //Поиск поля             
                if (listItems.Count > 0 && authorField!=null)
                {
                    gridDataSource=listItems.Cast<SPListItem>().Select(n => new DemandGridStruct
                    {
                        Id=n.ID,
                        DemendMean = (string) n["Title"],
                        Applicant = n["_x0437__x0430__x044f__x0432__x04"] ?? n[authorField.Id],
                        State = (string)n["_x0441__x0442__x0430__x0442__x04"],
                        CreateDate=(DateTime)n["Created"]
                    });

                }