濒危植物——半日花大,小孢子发生和雌,雄配子体形成

通过对半日花大、小孢子发生和雌、雄配子体形成过程的研究，得出以下结果：１）花药由四个花粉囊组成，药壁包括表皮、药室内壁、中层及绒毡层。药壁发育为双子叶型。腺质绒毡层；２）小孢子孢原为多细胞。小孢子母细胞减数分裂同时型，四分体排列方式为四面体型。成熟花粉２－细胞并具３孔沟；３）例生胚珠，双珠被，厚珠心。大孢子多泡原。四分孢子直线形或Ｔ字形。合点端的三个大孢子退化，瑞孔端的一个大孢子发育成功能大孢子、

Mega and Microsporogenesis and the Formation of Male and Female Gametophytes in an Endangered Plant --Helianthemum Soongoricum Schrenk

The paper deals with the mega and microsporogenesis and the formation of male and female gametophytes in Helianthemum Soongoricum Schrenk.The results are as follows:1)The anther is tetrasporangiate,the anther wall comprises the epidermis,fibrous endothecium,and ephemeral middle layer and glandular tapetum,its development follows dicotyledonous type;2)Microspore archesporium is of multicellular.Simultaneous type in the microspore mother cell follows meiosis and the microspore tetrads are tetrahedral arrangement.Pollen grains are 2 celled,and the ripe pollen which are 3 colporate;3)The ovule is anatropous,bitegument and crassinucellus.Megaspore archesporium is of multicellular.The development of embryo sac conforms to the Oenothera type.The magaspore mother cell undergoes meiosis to form a linear or T shaped tetrad.Only the micropyle megaspore functions and forms the female gametophyte,where as the other three degenerate;4)The hypostase appears at the stage of the mature embryo sac.It persists at the mature embryo stage.