Biological specificity of the antheridogen. from Ceratopteris thalictroides (L.) Brongn.

The relationship of the antheridogen from Ceratopteris thalictroides (L.) Brongn. (Antheridogen C) to three other known antheridogens, gibberellic acid, and two natural antheridogens, one from Pteridium aquilinum (Antheridogen A) and one from Anemia phyllitidis (Antheridogen B), is investigated. It is shown that each is a biologically distinet entity, interspecific activity being absent. The antheridogen responses of two widely separated sources of C. thalictroides were also compared. The results indicate that both susceptibility and antheridogen production vary between the two sources.