Purification of a Specific Inducer of the Male Sex Organ in Certain Fern Species

Abstract

A NATURALLY occurring, highly specific substance has been found which induces vegetative cells of gametophytes of certain fern species to differentiate and organize the male sex organ or antheridium. Döpp¹ showed that a water extract of mature prothalli of the common bracken fern Pteridium aquilinum hastened the formation of antheridia in young prothalli of this and of another fern species. He was inclined to interpret his findings to indicate that antheridia were initiated by way of non-specific growth inhibition. Näf² reported that the promotion of antheridium formation by the extract was due to a specific antheridium-inducing factor rather than to non-specific growth inhibition. The biologically active factor was found to induce antheridium formation in representatives of 7 of the 9 sub-groups of the family Polypodiaceae listed by Eames³ as well as in Dennstaedtia punctilobula, a member of the family Dicksoniaceae⁴. It appeared likely, therefore, that a relatively simple chemical substance is capable of directing morphogenesis in a highly specific way. In view of its unique properties, an attempt was made to isolate and characterize chemically the biologically active material. The present report describes a procedure for the purification of this substance.