Endogenous fusicoccin‐like ligand revealed in higher plants by radioreceptor and radioimmunoassays

Abstract
Radioimmuno- and radioreceptor assays were developed for quantitating fusicoccin-like substances in plants. FC-like ligands were found in cultured horseradish roots (70–90 pmol/g) and headed cabbage leaves (9–11 pmol/g). Detection of FC-like ligands in sterile root culture further argues in favour of endogenous fusicoccin representing a new type of phytohormone.