Sex-hormones in Neurospora crassa. Differences in the biological property of the hormonal extracts of fertile and sterile strains.

Sexual hormones, isolated from the wild strains and sterile mutants of Neurospora crassa, were used for the improvement of fertility of sterile crosses, i. e., St. L. a X7232-A, St. L. a X 9312-A and St. L. A X 8455-a. Improvement of fertility was observed in case of the cross St. L. a X 9312-A. Of the different extracts, hormonal substances present in the extract of 7232-A (sterile mutant) and also of the wild types (Em A, Em a, St. L. A, St. L. a) exerted the most prominent effects. For the extracts of other mutants such a conclusion was difficult to draw. The implications of these findings are being discussed.