【摘要】 <正> 单倍体植株小孢子母细胞减数分裂现象,一些作者曾作过大量观察,但有关大孢子发生过程中减数分裂和胚囊发育情况,工作和报道较少。本文较为系统地观察了花药培养得到的再生单倍体植株大孢子母细胞减数分裂和胚囊发育过程,从大孢子角度为单倍体植物增添了具体的细胞学和胚胎学内容。供试材料烟草(Nicotiana tabacum c.)“金星”品种(2n=48)花药接种于附加KT 2毫克/升,IAA 0.5毫克/升的H固体培养基上。约40天形成愈伤组织后转移到NAA 0.15毫克/升,IAA 0.375毫克/升的MS固体培养基上,待分化出小苗后经盆栽适应,再定植于大田中。用FAA和纳瓦兴液固定单倍体植株不同长度花更多还原

【Abstract】 The meiosis of MMC(megaspore mothercell) and process of ES (embryo sac) deve-lopment in N.tabacum L.haploid pollenplants were studied in this paper.The abnor-mality of meiotic division appears as stickeswith various degree at pachytene and diaki-nesis.At the metaphase Ⅰ,univalem scatteredin cytoplasm,or some chromosomes concen-trate on the plate,at times spindle bend toa sickle.At the anaphase Ⅰ and telophase Ⅰlagging chromosomes and micronuclei oftenwere discovered.At the anaphase Ⅱ and telo-phase Ⅱ,chromosomal bridges and micronu-clei also were observed.At the dyad stagethe cells began to degenerate for various de-gree.Development of the tetrad and func-tional megaspore also stopped and degenera-ted.Individual ES might develop to fournucleate stage,but it degenerate later on.Af-ter eight nucleate stage,but the further de-velopment of ES were not observed.Becauseof abnormality of meiosis,female gametophyteaborted at dyad-four nucleate ES.更多还原