【摘要】 利用常规石蜡制片技术,对紫葳科梓属黄金树的大、小孢子发生与雌、雄配子体的形成过程进行观察。结果表明:黄金树每朵花含有5枚雄蕊,其中2枚可育,3枚退化;可育雄蕊的花药为四囊型,花药壁4~6层,分别为表皮、药室内壁、中层(1~3层)和绒毡层,药壁的发育属于基本型,腺质绒毡层;孢原细胞为多孢原起源,小孢子母细胞减数分裂的胞质分裂为同时型,小孢子四分体的排列方式为正四面体型和左右对称型;复合花粉粒,由小孢子母细胞减数分裂生成的4个小孢子组成;成熟花粉二细胞型;胚珠倒生,双珠被,薄珠心,珠心表皮下的孢原细胞直接发育为大孢子母细胞,减数分裂产生直线型四分体,合点端的一个大孢子分化为功能大孢子,胚囊发育属于蓼型;同一朵花中雄配子体的发育略早于雌配子体,但雌雄同熟。更多还原

【Abstract】 The megasporogenesis, microsporogenesis and formation of female and male gametophyte of Catalpa specioca were observed using conventional paraffin section technology. The results showed that each flower of C. specioca contains five stamens,two of which are fertile stamens and the others are staminodia. The anther of the fertile stamen is tetrasporangiate, and its anther wall is composed of four to six layers: epidermis, endothecium, one to three middle layers and tapetum. The development of anther wall is basic type and tapetum belongs to glandular type. Archesporium is milti-provenace. Simultaneous cytokinesis in microspore mother cells follows meiosis to produce tetrahedral tetrad as well as isobilateral tetrad. Every compound pollen grain comprises four microspores derived from one microspore mother cell. Pollen grains are 2-celled when shed. The ovule is anatropous, bitegminous and tenuinucellate. The archesporial cell below nucellus epidermis functions directly as the megaspore mother cell. The chalazal megaspore of linear tetrad develops into a Polygonum-type embryo sac. In the same bud, the stamen develops earlier than the pistil, but maturates almost at the same time.更多还原