土沉香小孢子发生与雄配子体发育的细胞学观察

利用普通光学显微镜对土沉香小孢子发生与雄配子体发育的过程进行了观察。结果表明:土沉香小孢子发生与雄配子体发育过程均正常;花药4室,花粉囊壁由4层细胞组成,分别是表皮、药室内壁、中层和绒毡层,绒毡层的类型为腺质绒毡层,药壁形成方式为双子叶型;小孢子母细胞减数分裂过程中的胞质分裂为同时型,形成的四分体大多为四面体型,少数为左右对称型;成熟花粉粒为二细胞型。还利用扫描电镜对土沉香的成熟花粉进行了观察,发现成熟花粉呈球形,表面为具钝三角形投影的基柱所组成。萌发孔小,边缘不清晰,不易被观察到。

Cytological observations of microsporogenesis and male gametophyte development of Aquilaria sinensis (Lour.) Spreng

Using an ordinary optical microscope, we investigated the microsporogenesis and male gametophyte development of Aquilaria sinensis. The results show that microsporogenesis and male gametophyte development of A.sinensis are normal. The anther has four chambers. The pollen sac wall consists of four layers, i.e. epidermis, endothecium, middle layer and tapetum; the tapetum is of a glandular type. The formation of the anther wall shows a dicotyledonous type. Cytokinesis occurs simultaneously with meiosis in a microspore mother cell, and the formed tetrads are mostly tetrahedral while some are symmetrical. The mature pollen grains are of a binuclear type. Using a scanning electronic microscope (SEM), the mature pollen grains were observed, which appeared spherical in shape, with their surface made up of blunt-triangular projected pillars. The germination pores of the pollen were difficult to observe because of their small size and unclear edges.