Abstract
The sexuality of homosporous fern gametophytes is generally controlled by antheridiogen, a pheromone that promotes maleness. In this work, we examined whether photomorphogenically active light affects the antheridiogen-induced male development in the gametophytes of Ceratopteris richardii. It was found that the gametophytes of her1 mutant, which are insensitive to Ceratopteris antheridiogen (ACe), developed into male when they were grown under blue light in the presence of ACe. In the wild-type gametophytes, however, the blue light-irradiation did not affect the sensitivity to ACe, probably due to the saturation of ACe-sensitivity in the dark. Indeed, in the gametophytes of C. thalictroides, which is other Ceratopteris species and showed low antheridiogen-sensitivity in the dark, the blue light-irradiation increased the male development. Thus, we think that another ACe-signal transduction pathway that is activated by blue light latently exists in the gametophytes of C. richardii.
