All actions and proceedings brought by or against personal  representatives or collectors upon any cause of action or right to which the estate of the decedent is the real party in interest, must be brought by or against them in their representative capacity. (1868-9, c. 113, s. 79; Code, s. 1507; Rev., s. 160; C.S., s. 164; 1973, c. 1329, s. 3.)