洋葱卵细胞的分离

将洋葱的胚珠置于酶液中酶解50~110 min后剥去其珠被,可清楚地看到珠心中的胚囊轮廓。用解剖针将珠心从中部横切,然后挤压其珠孔部位,卵器细胞从胚珠的切口处逸出。再用显微操作仪的玻璃针将卵细胞和两个助细胞分开,达到分离洋葱卵细胞的目的。酶对分离卵细胞具有重要作用,在最佳的酶液浓度[0.02%果胶酶Y23、0.08%果胶酶(Serva)、0.05%纤维素酶和0.05%半纤维素酶]下酶解胚珠110 min后,解剖1 h可从24个胚珠中分离出10个卵细胞(41.67%)。随着胚囊的发育,两个助细胞的体积出现明显的二形性。洋葱生活卵细胞的分离为开展洋葱离体受精建立了基础,也为研究洋葱卵器细胞的发育创造了条件。     

葱卵细胞的分离

将大葱(Allium fistulosum)胚珠置于酶液中30分钟可将其外珠被去掉。可清楚地看到由内珠被包裹的胚珠中胚囊的轮廓。将胚珠转移至不含酶的相同溶液中, 用解剖针从胚珠中部切割, 然后挤压胚珠的珠孔部位, 卵器细胞从胚珠的切口处逸出。再用显微操作仪将卵细胞和2个助细胞分开, 达到葱卵细胞分离的目的。酶对分离卵细胞具有重要的作用, 经0.2%果胶酶Y23、0.8%果胶酶、0.8%纤维素酶和0.5%半纤维素酶的处理, 可在2小时内从30 个胚珠中分离出18个卵细胞。随着胚囊的发育, 2个助细胞的体积出现明显差异。生活的葱卵细胞的成功分离, 为建立葱离体受精体系创造了条件。     

葱卵细胞的分离

将大葱（Allium fistulosum）胚珠置于酶液中30分钟可将其外珠被去掉。可清楚地看到由内珠被包裹的胚珠中胚囊的轮廓。将胚珠转移至不含酶的相同溶液中,用解剖针从胚珠中部切割,然后挤压胚珠的珠孔部位,卵器细胞从胚珠的切口处逸出。再用显微操作仪将卵细胞和2个助细胞分开,达到葱卵细胞分离的目的。酶对分离卵细胞具有重要的作用,经0．2％果胶酶Y23、0．8％果胶酶、0．8％纤维素酶和0．5％半纤维素酶的处理,可在2小时内从30个胚珠中分离出18个卵细胞。随着胚囊的发育,2个助细胞的体积出现明显差异。生活的葱卵细胞的成功分离,为建立葱离体受精体系创造了条件。     

水稻卵细胞与合子的分离

水稻卵细胞与合子的分离韩红梅赵洁施华中杨弘远周嫦（武汉大学生命科学学院植物生殖生物学研究室武汉４３００７２）关键词水稻,卵细胞,合子,分离ＩＳＯＬＡＴＩＯＮＯＦＥＧＧＣＥＬＬＳＡＮＤＺＹＧＯＴＥＳＩＮＯＲＹＺＡＳＡＴＩＶＡＨＡＮＨｏｎｇＭｅｉＺ...     

分离烟草胚囊的新方法及诱导卵细胞与助细胞原生质体的原位融合

用渗透压冲击和酶解相结合的技术,成功地分离出大量形态完整、结构清晰的烟草生活胚囊。此法用酶浓度低,操作时间短、例于纯化,易于分离胚囊细胞原生质体,为植物雌性细胞操作提供了一种较实用的技术。此外,通过整溶液渗透压,可有效地控制及诱导卵细胞与助细胞原生质体的原位融合。     

蓝猪耳卵细胞和合子的分离

蓝猪耳(Torenia fournieri)胚囊部分裸露出胚珠,在光学显微镜下能清楚观察到卵细胞和助细胞的形态结构.用解剖和酶解-解剖两种方法都能分离出生活卵细胞.用前种方法机械分离出的卵细胞数量较少(5%),但避免了酶对配子识别研究的干扰.在后种方法中加入0.1%纤维素酶和0.1%果胶酶既能使分离更加容易操作,又对卵细胞没有致命伤害,能在短时间内分离出较多的卵细胞(18%).用酶解-解剖方法也可分离出授粉14 h后的合子细胞.     

黄花木本曼陀罗卵细胞分离(简报)

采用分离的精、卵细胞体外融合并诱导人工合子长成植株的离体受精方法可在没有其他组织影响的单细胞水平上探索受精事件的发生过程．为研究高等植物的受精机理、探索配子识别和合子激活等问题提供有效手段。分离的卵细胞不仅可以用来开展离体受精研究．也提供了用分子生物学方法研究被子植物卵细胞发育和合子发育机理的实验基础.     

洋葱伯克霍尔德菌CF_66抗菌物质的分离纯化及性质的研究

洋葱伯克霍尔德菌CF_66能够抑制立枯丝核菌等若干植物病原菌和其它一些真菌的生长。CF_66菌发酵液的粗提液通过Sephadex_75pg、Sephacryl S_100柱层析分离纯化,获得抗菌物质CF66I。此抗菌物质耐热性强,耐碱,但在强酸性条件下不稳定。低浓度有机溶剂的存在有利于抑菌活性的提高。对其结构的研究表明CF66I是以(CH2CH2O)n为主要单元结构并带有酰氨键的化合物。     

洋葱伯克霍尔德菌CF_66抗菌物质的分离纯化及性质的研究

洋葱伯克霍尔德菌CF-66能够抑制立枯丝核菌等若干植物病原菌和其它一些真菌的生长。CF-66菌发酵液的粗提液通过Sephadex-75pg、Sephacryl S-100柱层析分离纯化,获得抗菌物质CF66I。此抗菌物质耐热性强,耐碱,但在强酸性条件下不稳定。低浓度有机溶剂的存在有利于抑菌活性的提高。对其结构的研究表明CF66I是以(CH2CH2O)n为主要单元结构并带有酰氨键的化合物。     

胡萝卜精、卵细胞、助细胞和中央细胞的分离

用两个解剖针挤压胡萝卜花粉使其破裂释放出精细胞。用酶解-解剖方法分离胡萝卜胚囊中的卵细胞、助细胞和中央细胞。胡萝卜胚珠先在酶液中酶解40~50min,然后将其转移到不含酶的分离液中用解剖针解剖胚珠。将胚珠的合点端切破,轻轻挤压胚珠的珠孔,卵细胞、助细胞和中央细胞即可逸出。在最佳条件下,20min可从20个胚珠中分离出5个卵细胞。对分离胚囊细胞的渗透压和酶液成分进行了筛选。分离出的卵细胞用显微操作仪收集。胡萝卜精、卵细胞的成功分离为在双子叶植物中进行离体受精探索创造了条件。     

洋葱小孢子母细胞减数分裂过程中微管分布变化

应用间接免疫荧光标记技术和激光共聚焦扫描显微镜成像技术观察洋葱小孢子母细胞减数分裂过程中微管分布变化。减数分裂之前,小孢子母细胞中的微管较短,呈辐射状,由细胞核表面向四周扩散。减数分裂开始后,细胞质中的一部分微管蛋白聚集成纺锤体微管,控制染色体的分布。进入减数分裂I后期,纺锤体微管变为牵引染色体移向两极的着丝粒微管和连接纺锤体两极的极丝微管。之后,所有微管集中在两个核之间,构成成膜体。然后,微管解聚成微管蛋白弥散在细胞质中。减数分裂I完成后,二分体2个子细胞中的微管蛋白又聚集成2个纺锤体微管,开始减数分裂II过程。经过减数分裂II中期,2个二分体细胞中的微管再次集中在2个细胞核之间形成成膜体,隔离2个细胞核。此后,微管蛋白解聚,弥散分布在小孢子细胞质中。     

洋葱花药发育中钙离子分布特征

采用焦锑酸钾沉淀钙离子技术,对洋葱（Alliumcepa）花药发育中Ca^2＋分布进行了研究。在小孢子母细胞时期,小孢子母细胞中的钙沉淀颗粒很少,但绒毡层细胞的内切向壁已出现明显的钙沉淀颗粒。在四分体时期,四分体小孢子的胼胝质壁中出现较多的钙沉淀颗粒;绒毡层细胞内切向壁的钙沉淀颗粒消失,而在外切向壁和径向壁部位的钙沉淀颗粒增加。在小孢子早期,小孢子中也出现了钙沉淀颗粒,而绒毡层细胞内切向壁表面出现了很多絮状物,其上附有细小钙沉淀颗粒。到小孢子晚期,小孢子中出现一些小液泡,细胞质中的钙沉淀颗粒有所下降。此时绒毡层细胞已明显退化,但在绒毡层膜上仍有一些乌氏体和钙沉淀颗粒。在二胞花粉早期,营养细胞中的液泡收缩、消失,细胞质中又出现了较多的钙沉淀颗粒,在质体和其内部的淀粉粒表面上附有较多的钙沉淀颗粒。到二胞花粉晚期,花粉中的钙沉淀颗粒已明显下降,仅在花粉外壁中还有一地钙沉淀颗粒．     

Somatic embryogenesis and plant regeneration from immature embryo cultures of onion (Allium cepa L.)

Somatic embryos were obtained and plants regenerated from immature embryos of onion following culture on embryogenic induction media. Highest rates of somatic embrogenesis resulted from 0.5- to 1.5-mm immature embryos cultured on media containing 5 mg/l of picloram. Somatic embryos formed either directly on the surface of embryos or developed from compact cultures. The production of somatic embryos was significantly affected by the addition of auxin, embryo size and cultivar. The potential of somatic embryogenic cultures for plantlet regeneration has been maintained for over 1 year in some lines. Three types of immature-embryo-derived cultures were characterized by histology. Some cultures were morphologically similar to immature-embryo-derived embryogenic cultures of other monocotyledonous species. Cultures such as these have proven to be useful target tissues in transformation studies. Received: 16 December 1997 / Revision received: 23 February 1998 / Accepted: 13 March 1998     

Variations in gynogenic response among long-day onion (Allium cepa L.) accessions

Long-day onion genotypes originating from Europe, North America and Japan were tested for gynogenic induction ability. Haploid induction using an efficient single-step flower culture induction procedure was at least as productive as the previously studied double-step flower/ovary culture, while undesired callusing of flower bases did not substantially lower the induction frequency. Differences in embryo yields among different accessions and among different donor plants within accessions were very pronounced. Three extremely responsive accessions were found, with average embryo yields of 18.6–22.6%, while individual donor plants produced up to 51.7% embryos. In terms of geographic origin, genetic material bred in America was on average almost five and nine times more responsive than European and Japanese material, respectively. The stability of high induction frequency was confirmed by culturing flowers from the same individual donor plants in two subsequent growth years. Of the regenerants, 90.5% were haploid and 88.2% of analysed diploid regenerants were homozygous. The results indicate that the genotype of donor plants has a crucial influence on haploid induction ability and that the less labour intensive single-step flower induction procedure is an efficient method of obtaining a high-frequency homozygous-embryo induction rate. Received: 20 November 1997 / Revision received: 13 March 1998 / Accepted: 30 March 1998     

A comparison of four selective agents for use with Allium cepa L. immature embryos and immature embryo-derived cultures

The efficacy of antibiotics, kanamycin, hygromycin, and geneticin, and the herbicide phosphinothricin as selective agents in onion (Allium cepa L.) tissue culture was investigated. Immature embryos and immature-embryo-derived cultures were grown on media containing a range of concentrations of the four selective agents. Kanamycin was shown to be unsuitable while phosphinothricin, geneticin or hygromycin significantly reduced further growth of the onion cultures. The level of casein affected growth on medium containing phosphinothricin. The effectiveness of phosphinothricin was reduced when high levels (200 mg/l) of casein were present in the medium. Omission of casein reduced the shoot regeneration frequency from immature embryo cultures. Low levels of hygromycin (10–30 mg/l) reduced callus growth but significantly increased the regeneration frequency from immature-embryo-derived cultures. Received: 12 September 1997 / Revision received: 5 December 1997 / Accepted: 13 March 1989     

洋葱花粉母细胞细胞内、细胞间微梁骨架的超微结构观察(英文)

以洋葱(AlliumcepaL.)花粉母细胞为材料,采用DGD包埋去包埋原位技术,对花粉母细胞不同发育时期的细胞内、细胞间微梁骨架的超微结构进行了电镜观察。结果发现,花粉母细胞核内存在粗细不等的微梁骨架,与核仁和染色体紧密相连,随着发育的推移,其均一性发生改变。在核周有核纤层样的结构存在,与细胞核和胞质中的微梁骨架紧密相连,到前期结束时解体。洋葱花粉母细胞内具有发达的胞质微梁骨架,这种结构在减数分裂前期Ⅰ变化不明显。在胞间连接(胞间连丝和胞质通道)内,也有精细的微梁骨架分布,并且与两端细胞中的骨架相连。在凝线期的花粉母细胞中观察到细胞融合现象,有胞质或核内微梁骨架与穿壁转移的胞质小球和核小球内骨架相连。此时细胞核偏向一边,但细胞的其余部位仍充满了胞质微梁骨架。初步探讨了核微梁骨架与核仁和染色体之间的关系,核纤层与细胞核之间的关系,以及细胞内、细胞间微梁骨架与细胞融合之间的关系     

Ultrastructural Observation on the Intra- and Intercellular Microtrabecular Network of the Pollen Mother Cells in Onion (Allium cepa)

Using DGD embedment-free electron microscopy, ultrastructural observation on the intra- and intercellular microtrabecular network (MN) of the pollen mother cells (PMC) of the whole meiotic prophase Ⅰ in onion ( Allium cepa L.) was performed. Complex nuclear MN was observed in the nucleus of PMCs, spreading throughout the nuclear region. The nucleolus and chromosomes were connected with the MN filament network. The uniformity of nuclear MN changed with the development of the PMCs. A lamina-like structure surrounded the nucleus and joined the MN in nucleus and in cytoplasm, but it disassembled at the end of prophase Ⅰ. There was also a complex cytoplasmic MN in PMCs, without obvious variation during the prophase Ⅰ. Furthermore, MN in cytoplasmic connections (plasmodesmata and cytoplasmic channels) was noticed to link the frameworks in two neighboring PMCs into one entity. Cytomixis was observed at synizesis of prophase Ⅰ in this experiment, and MN in cytoplasm and in nucleus was noticed to distribute in these granules which migrated from one PMC into its neighboring cell. At this time the nucleus moved aside from center of the PMC, but the rest of the cell was still fulfilled with MN filaments. The relationships of nuclear MN with nucleolus and chromosomes, lamina with nucleus, as well as intra- and intercellular MN with cytomixis are discussed in this paper.     

Fidelity of Hymenoptera and Diptera pollinators in onion (Allium cepa L.) pollination

Onion (Allium cepa L.) is protandrous in nature and requires cross‐pollination to avoid inbreeding. The pollination potential of native bees (Hymenoptera) and true flies (Diptera) was assessed in the perspective of finding the best pollinators for onion cross‐pollination and seed multiplication. The community of pollinators was composed of four bee species and twelve true fly species. Episyrphus balteatus, Eupeodes sp., Musca domestica and Eristalinus aeneus were the most abundant pollinators. The maximum pollinator activity was observed from 12 to 24 days after opening of the flowers. The pollination effectiveness of tested bees (Apis dorsata and Apis florea) was greater than true flies (E. balteatus, Eupeodes sp., M. domestica, E. aeneus and Callihoridae sp.) in terms of Spears values.