西域旌节花的雌雄配子体发育及其系统学启示

研究西域旌节花（Stachyurus himalaicus Hook.f.et Thoms.ex Benth)雌雄配子体的形成和发育过程，并与“近缘”类群（山茶科，猕猴桃科，山柳科，省沽油科，堇菜科，金缕梅科和Crossomataceae等）的胚胎学特征进行了比较，西域旌节花主要胚胎学特征可概括为：四囊型花药，药壁形成方式为基础型，花药壁由表皮，药室内壁，2-3层中层和绒毡层组成，药室内壁纤维质加厚，腺质绒毡层，小孢子母细胞减数分裂为同时型，小孢子四分体呈四面体形排列，花粉散发时为二细胞，胚珠倒生，双珠被，厚珠心，珠孔由内，外珠被构成，具珠心冠和承珠盘，蓼型胚囊，从目前可资利用的雌雄配子体形成和发育的资料来看，旌节花科与堇菜科最为接近，与金缕梅科的关系值得注意，而与山柳科和猕猴桃科以及山茶科的关系相对疏远，胚胎学证据不支持Nandi等（1998）揭示的旌节花科与Crossosomataceae的姐妹群关系，但他们的分析结果在某种程度上仍然得到了胚胎学证据的支持。

The Development of Male and Female Gametophytes of Stachyurus himalaicus and Its Systematic Enlightenment

This paper deals with the formation and development of both male and female gametophytes of Stachyurus himalaicus and a comparison of embryological features was made among Stachyuraceae and its related taxa such as Theaceae, Actinidiaceae, Clethraceae, Staphyleaceae, Violaceae, Hamamelidaceae and Crossosomataceae. The embryology features of Stachyurus himalaicus may be summarized as follows. The wall of the tetrasporangiate anther comprises the epidermis, fibrous endothecium, two or three middle layers and glandular tapetum, with a wall formation of basic type. By miosis, the microspore mother cells undergo simultaneous cytokinesis and so result in the tetrahedral microspore tetrads. The pollen grains shed at two-celled stage. The ovules are anatropous, bitegminous and crassinucellate. Both the inner and the outer integuments take part in the formation of micropyle. The nucellar cap and hypostase are developed. The chalazal or sub-chalazal megaspore is functional, developing into a Polygonum type embryo sac. Embryologically, Stachyuraceae is more similar to Violaceae and Hamamelidaceae, but the families of Clethraceae, Actinidiaceae and Theaceae seem to be more stand off from Stachyuraceae. The progressively sister relationship between Stachyuraceae and Crossomataceae as well as Staphyleaceae, revealed by Nandi et al. in 1998, is not supported by embryology.