Identification of gibberellin A9 methyl ester as a natural substance regulating formation of reproductive organs in Lygodium japonicum.

Prothallia of Lygodium japonicum (Thunb.) Sw. were aseptically cultured under white light in a mineral solution. Solvent fractionation of the resultant culture medium and subsequent preparative thinlayer chromatography yielded a fraction that induced antheridium formation and inhibited archegonium formation. Combined gas chromatography-selected ion monitoring analysis of this fraction confirmed the presence of gibberellin A9 methyl ester (GA9-me) as an antheridiogen and an inhibitor of archegonium formation. Exogenously applied [(3)H]GA9 was rapidly converted to [(3)H]GA9-me in the prothallial tissue. Authentic GA9-me was active to 10(-10)M in antheridium formation and to 10(-9)M in the inhibition of archegonium formation.