黄山梅大小孢子发生和雌雄配子体发育的观察研究

he megasporogenesis, microsporogenesis and the devel opment of female and male gametophyte of endangered species Kirengeshoma Palmata were observed by means of traditional paraffin wax sections . The main conclusions were drawn as follows: (1) The mature wall of anther consists of four or five layers, including epidermis, endothecium, one or two middle layers and tapetum from out to inside, which belongs t o basic type . Tapetum cell is of secretory type . (2) The tetrahedral tetrads are born following the cytokinesis of microsporocyte meiotic division . The mature pollen grains are two-celled at the dis persal stage . (3)The aborted and normal pollen grains were observed in the same anther, however, the percentage of this aborted phenomenon was only 1.5%. (4) The ovary was composed of three or four fused carpels in one flower with axile placentation and the ovules were anatropous，bitegminous and crassinucellate. The mature embryo sacs were of the Polygonum type. These results suggest that mega- and microspores and male- and female gametophytes were not the endangered bottleneck.