Abstract: The gametophyte development of Athyrium fallaciosum was observed in sterile culture.The results showed that the spore is tetrahedral type;the spore germination is of the Vittaria-type and the gametophyte development is of the Adiantum-type. Adult gametophyte is cordate;the antheridia is nearly spherical; the mature archegonia is slender and often apply to the prothallus base tilted or curved. The gametophytes of A.fallaciosum were female, male, hermaphroditic and asexual gametophytes by using routine propagation. Sowing density affected gametophyte sexual expression and showed a certain trend. With density increased, male gametophytes increased and female gametophytes first increased and then decreased. Hermaphroditic gametophytes and asexual gametophytes sexual expression were not affected by density. The number of archegonia of female gametophytes and hermaphroditic gametophytes is 10~15. When density increased, the number of antheridia decreased. There were about 50 antheridias of male gametophyte, while about 20 antheridias of hermaphroditic gametophyte.

Key words: Athyrium fallaciosum, gametophyte development, density, sexual expression