花粉

Inflorescence differentiation can be divided into 6 phases: primary, rundlet primordium, floret primordium, pistil and stamen primordium, initial reproduction structure and pollen maturation.

根据观察结果，将北柴胡花序分化进程划分为初生期、小伞原基分化期、小花原基分化期、雌雄蕊原基分化期、生殖结构分化始期和花粉粒完熟期6个时期。

Three group male sterile and maintenance lines of monogerm sugar beet as materials were used, we observed the biological characters of their buds, anthers and anther structure, and the development process of pollens by the methods of conventional Paraffin Slicer, Safranine Ai-Shi Haematine Crystal and Fast Green.

方法］以3对单胚型甜菜雄性不育系和保持系为试验材料，采用常规的石蜡切片方法，对花蕾和花药的生物学特性以及花药结构、花粉发育过程进行比较。

Particular matter which is absorbable, such as dust, pollen, Hair,scurf, smoke etc..

能够进入人体喉部以下呼吸道的颗粒物。如尘埃、花粉、香烟、烟雾等。

At this time, everywhere is a sea-green edge望不到, set off a red, white, yellow and purple ...... all sorts of wild flowers, a breeze blowing潮润, that grass pollen rich atmosphere, vertical heart drilling.

这时，遍野是望不到边的绿海，衬托着红的、白的、黄的、紫的……种种野花卉，一阵潮润的微风吹来，那浓郁的花粉青草气息，直向人心里钻。

In this paper, FT IR is used to investigate the effects of strong sound waves at different frequency and strength on the secondary conformation of the cell wall proteins of tobacco cells.

本论文采用傅里叶红外光研究烟草花粉细胞在不同频率和不同功率的强声波作用下，细胞壁蛋白质二级结构的变化。

The natural levee and overflow facies have more Pinus, Selaginella and local plant pollen grains.

自然堤和泛滥相以含有较多的松、卷柏孢子和当地花粉植物为特徵。

Chromosome pairing behavior in meiosis of the hybrid F1 was carried out. Results showed that in an average , 1.25 rod bivalents were observed in one PMC, meiotic configuration was 2n=14=11.49Ⅰ+1.25Ⅱ(Xta=1.25) and most of PMCs possessed 1～5 bivalens, indicating that the relatively high homeology was detected between the D genome of Ae.tauschii and the V genome of D.villosum. The morphological differences between F1 hybrids and their parents were significant. F1 plants were highly self-sterile, but partially self-fertile after treated by chromosome doubling technique.

对杂种F1花粉母细胞减数分裂中期Ⅰ染色体配对行为进行观察发现，"节节麦×簇毛麦"杂种F1平均每PMC有1.25个棒状二价体，染色体的平均构型为2n=14=11.49Ⅰ+1.25Ⅱ(Xta=1.25)，大部分被观察的细胞出现1～5个二价体，表明节节麦D染色体与簇毛麦V染色体间具有相对较高的部分同源配对， D和V染色体之间存在一定的部分同源性。F1植株高度自交不育，经染色体加倍处理后能够自交结实。

F1 hybrid has the morphological feature which is between the male and female parents and shoed strong heterosis, exuberant vitality, late ripe period and low rate of self-fertility. The average chromosome configuration of F1 in PMC MI was 18.58Ⅰ+18.59Ⅱ+0.085Ⅲ+0.028Ⅳ. At anphase Ⅰ in PMC, some laggard chromosomes arranged in equatorial plate. Micronucleus and a lot of abnormal cells can be observed at dyad, tetrad and microspore.

杂种F1形态特征介于双亲之间，具有较强的杂种优势，生长旺盛，熟期晚，自交结实率较低。F1花粉母细胞减数分裂中期Ⅰ平均染色体构型为18.58Ⅰ+18.59Ⅱ+0.085Ⅲ+0.028Ⅳ，PMC后期Ⅰ观察到部分落后染色体排列在赤道板上；二分体、四分体和小孢子时期，细胞内普遍观察到微核，且出现大量异形细胞。

In order to obtain factual information about self-fertilization, empirical measurements must be made.

为了得到关于自传花粉的确实资料，必须采用一些已行之有效的方法。

In order to obta in factual in formation about self-fertilization, empirical measurements must be made

为了得到关于自传花粉的确实资料，必须采用一些已行之有效的方法。

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。