Abstract
Among vascular plants, seed plants (Angiosperms and Gymnosperms) have been well studied for the endogenous brassinosteroids. However, any concrete evidence for the occurrence of brassinosteroids in ferns, seedless vascular plants, has not been obtained. In this study we analyzed some ferns for the presence of brassinosteroids by using GC-MS. The ferns examined were Equisetum arvence (vegetative shoot and reproductive shoot, Thelypteris decursive-pinnata (leaf), Pteridium aquilinum (leaf), Osmunda japonica Thunb. (leaf). As the results, brassinosteroids were identified from all the tissues examined. As biologically-active brassinosteroids, castasterone but not brassinolide was identified. The biosynthetic precursors of castasterone were also identified, being the same as those in seed plants. The endogenous brassinosteroid profiles of the respective ferns will be discussed by comparing with those in Arabidopsis.
