梭梭的胚胎学研究 I.小孢子发生、雄配子体形成及大孢子发生过程中无融合生殖现象的初步观察

Study on Embryology of Haloxylon ammodendron I. Preliminary Observation on Microsporogenesis and Formation of Male Gametophytes and Apomixis in Megasporogenesis

对梭梭的大、小孢子发育和雌、雄配子体的形成过程进行研究后认为,梭梭小孢子孢原为多细胞,小孢子母细胞排列紧密,个别花药的小孢子母细胞彼此分开。小孢子母细胞减数分裂为同时型,四分体排列方式为四面体型。成熟花粉粒为三细胞。药壁由表皮、药室内壁、一层中层和腺质绒毡层组成。大孢子发育中未发现有减数分裂过程,只看到直接由孢原细胞发育的胚囊,推测为体细胞无孢子生殖的无融合生殖现象。

The mega-and microsporogenesis and the formation of the male and female gametophytes of Haloxylon ammodendron (C.A.Mey.) Bunge are studied in this paper. Archesporium is multicellular. Arrangement of microspore mother cells are compacted and very few microspore mother cells are interspersed in the anther. The microspore mother cells are simultaneous type in meiosis and the microspore tetrads are tetrahedral. The mature pollen grain is 3-celled type. The anther wall comprises the epidermis, endothecium, and ephemeral middle layer and glandular tapetum. The meiosis is not discovered in the megasporogenesis. The embryo sac alone come from archesporium. The results show that the phenomena of reproduction conforms to apospory.