粉叶小檗大孢子发生和雌配子体形成

采用石蜡切片方法对粉叶小檗（Berberis pruinosa Franch.)的大孢子发生和雌配子体形成过程进行了研究。主要结果如下：雌蕊1枚,子房单心皮,边缘胎座,2枚胚珠倒生,具双珠被,厚珠心,珠孔由内外两层珠被共同形成,呈“Z”字形;单孢原,位于珠心表皮下;直线形大孢子四分体,合点端的1个大孢子发育为功能大孢子,胚囊发育类型为蓼型;成熟胚囊中,2个极核在受精前融合为次生核;3个反足细胞不发达,较早退化;"品"字形卵器,其中助细胞发达且具丝状器。

Megasporegenesis and Female Gametophyte Development in Berberis pruinosa Franch.

The megasporogensis and female gametophyte formation in Berberis pruinosa were first studied through paraffin sectioning. The main results can be concluded as follows: solitary pistil is monocarpellary with 2 ovules, anatropous,marginal placenta, crassinucellate. The zig-zag micropyle is formed by both the inner and the outer integuments. Single archesporial cell is under nucellar epidermis. The tetrad of megaspores is linear shaped, with the first cell from the chalazal end being functional. The development of embryo sac belongs to the Polygonum type. In mature embryo sac, two polar nucleus fuse into the secondary nucleus before fertilization, three antipodal cells are ephemeral. Inside the triangular egg apparatus, two synergids with fifiform apparatus are developed.