长柱十大功劳大小孢子发生和雌雄配子体形成

Genesis of microspore,megaspore and the development of male gametophyte, female gametophyte in Mahonia duclouxiana Gagnep.

首次报道了长柱十大功劳(Mahonia duclouxiana Gagnep.)大小孢子发生和雌雄配子体形成过程.主要结果如下:花药4室,花药壁发育方式属双子叶型;药室内壁有带状加厚现象;腺质绒毡层,双核;多孢原,发生于表皮下;小孢子母细胞减数分裂的胞质分裂属连续型,形成双轴对称式四分体;散粉时花粉粒为2-细胞型,呈球形.雌蕊1枚1室,子房单心皮,边缘胎座,4～6枚胚珠,胚珠具双珠被,厚珠心;珠孔由两层珠被共同形成,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.

The microsporogenesis, megasporogensis and the formation of male gametophyte and female game- tophyte in Mahonia duclouxiana were first reported. The main results can be concluded as follows： anthers are tetrasporangiate ; the wall development is dicotyledonous type ; glandular binucleate tapetum ; endothecium of the chamber develops characteristic banded thickening during the maturation. Cytokinesis of meiosis in microsporo- cyte is successive and the tetrads are biaxial symmetrical. Pollen grains are mainly 2 - cell type when shedding. Solitary pistil is monocarpellary with 4 -6 ovules, marginal placenta, crassinucellate with double integument. Mi- cropyle is formed in both inner and outer integument, shaped as ＂Z＂ ; single archesporial cell locates under nu- cellar epidermis; the tetrad of megaspores is linear, the first cell from the chalazal end develops functional mega- spore, the development of embryo sac is Polygonum type.