麦秆蹄盖蕨（Athyrium fallaciosum）配子体的发育规律及播种密度对配子体性别分化的影响

在组织培养条件下，对麦秆蹄盖蕨（Athyrium fallaciosum）配子体发育的连续过程进行了详细观察。结果表明:麦秆蹄盖蕨孢子为四面体型; 孢子萌发为书带蕨型（Vittaria-type）；原叶体发育为铁线蕨型（Adiantum-type），成熟原叶体为对称的心形；精子器近圆球形，成熟颈卵器细长，常向原叶体基部倾斜或弯曲。常规播种条件下，发现麦秆蹄盖蕨配子体有雌配子体、雄配子体、雌雄同体配子体和无性配子体类型。配子体的性别随密度不同而呈现一定的变化趋势，雄配子体随密度增大呈上升趋势；雌配子体随密度增大先上升后下降；雌雄同体配子体和无性配子体随密度变化不大。雌配子体和雌雄同体配子体具颈卵器数目一般为10～15个；精子器数目随密度的增大逐渐减少，雄配子体中具有约50个精子器，雌雄同体配子体具有约20个精子器。

The Gametophyte Development of Athyrium fallaciosum and Effect of Sowing Density on the Gametophyte Sexual Expression

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.