花粉

The effect of gamefocidal 2C derived from Aegilops cylindryca on meiosis and mitosis of pollen grains of triticale.

来自山羊草的杀配子染色体(Aegilops cylindryca 2C)对小黑麦减数分裂及花粉的有丝分裂的影响。

The pollen fertility of two-line hybrid rice and conventional rice was observed under normal and low temperature conditions.

考察了水稻常规品种及两系杂交稻在低温影响前后的花粉育性变化。

And during this very moment, unbeknown to the bee, it picks up the pollen.

就在这时，它已经粘到花粉了，但它自己还浑然不知。

A microscopic fossil,as of a pollen grain or unicellular organism.

微体化石一种微小的化石，如花粉粒或单细胞有机体的化石

Some large vacuoles appeared in the tapetal cells of the sterile anthers at the early uninucleate pollen stage.

在单核细胞早期，不育花粉的四分体细胞中有较明显的大液泡出现。

The results were as follows: 1.Inoculated on the induction medium at the late uninucleate stage,the microspores could initiate embryogenesis by first divisions in both symmetric and asymmetric patterns,but the former was predominant.

通过观察玉米小孢子胚胎发生的细胞形态学特征，发现：离体培养条件下单核后期的花粉可以通过均等分裂和不均等分裂两条途径形成胚状体，与前人的研究结果一致。

Osg6B, a promoter from rice, can direct gene expressing in anther tapetal during the early developmental stage of microspore from tetrad to uninucleate pollen, with high temporal and spatial specificity.

osg6B是来源于水稻花药绒毡层的特异性的启动子，它在小孢子发育的四分体时期至单核花粉期在花药绒毡层中特异启动基因的表达，它具有较为严紧的时空特异性。

Based on extrapolated organ shape criteria,we select ears that are in uninucleate period,carry out pretreatment in a 6~8℃ low-temperature condition for about 12 days, and callus induction rate can be enhanced in this way.② 1~2mm diameter should be the appropriate size for translocated callus,and plants grow to 4cm breeding for mature plants should be conducted in a timely manner.③ Get well down with sterilization,reduce contamination and strengthen greenhouse management,etc.

根据器官形态指标外推法选择花粉发育处于单核靠边期的幼穗，进行6~8℃低温预处理12d左右，可提高愈伤组织诱导率；②愈伤组织转移大小以直径1~2mm为宜，当绿苗长至4cm左右时及时进行壮苗培养；③做好接种材料、室内、人员的消毒和卫生工作，降低污染率，加强温室等的管理。

Microspore abortion of H9A occurred in the early uninucleate stage. The tapetum cells were in extreme hypertrophy so that tetrads were extruded to crack and break down and could not form normal uninucleate pollen grains; the abortion type was sporophyte.

结果表明，雄性不育材料H9A的小孢子败育发生在单核前期，由于绒毡层细胞极度膨胀，四分体受挤压后破裂并降解，无法形成正常的单核花粉粒，属于孢子体败育。

The observation showed that sterile plants and fertile plants in the pollen mother cell stage is not very different, when microspore mother cells of male sterile plants enter meiosis period, it could form normal tetrad cell , tetrad cell is normal in early development stage, In the uninucleate microspore stage , tapetal cells were vacuolization, the microspores were extruded to the middle by tapetal cells.

本研究利用石蜡切片法，结合光学显微镜技术对樱桃萝卜核质互作雄性不育系的不育株和对应保持系可育株的花药发育过程进行细胞形态学观察，观察结果表明：不育株与可育株在花粉母细胞时期差别不大，不育株的花药小孢子母细胞进入减数分裂期后，可以正常的形成四分体，四分体前期发育正常，而在单核小孢子期绒毡层细胞出现液泡化，绒毡层细胞向中间挤压小孢子。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。