SEXUAL DEVELOPMENT OF ONOCLEA SENSIBILIS ON AGAR AND SOIL MEDIA WITHOUT THE ADDITION OF ANTHERIDIOGEN

Onoclea sensibilis gametophytes grown on agar, unsterilized soil or ashed soil without the addition of antheridiogen developed antheridia after the notch meristem was formed. There was a linear increase in maleness through time on all three media. Antheridial production on agar was delayed nearly 3 wk. Agar had a significantly higher proportion of females than ashed soil or unsterilized soil. It was concluded that agar is an inappropriate medium for experiments on the mechanism of sexual development in Onoclea gametophytes.