珠孔

授粉后8~14h，花粉管在子房中生长并通过珠孔进入胚珠。自花粉萌发至花粉管长入珠孔大约需要1h。

8-14 hours after pollination , pollen tube grows in ovary and gets into ovule via micropyle . It is about 1 h from germination to the arrival at micropyle .

珠孔由内珠被和腹侧外珠被构成。

The micropyle is formed with inner integuments and partial outer integument .

授粉后1h花粉管经珠孔及珠心表皮细胞间隙进入1个助细胞，并释放精子。

One hour after pollination , pollen tube goes through the intercellular space of nucellar epidermis and enters one of the synergids , releases two sperms .

约18～24h，花粉管进入胚囊，破坏一个助细胞，并在其珠孔端释放两个精子；

In about 18 ~ 24 hours , the pollen tube enters the embryo sac and destroys one of the two synergids , releasing 2 sperms in the micropylar end .

利用扫描电子显微镜术和光学显微镜术研究了黄檗（PhellodendronamurenseRupr.）的珠孔塞和珠孔的形态发育和花粉管在雌蕊中的路径。

The developmental morphology of the obturator and micropyle and the pathway of the pollen tubes in the ovarian locule in Phellodendron amurense Rupr . have been investigated by scanning electron microscopy and light microscopy .

开花14～23d，胚珠中可见合子、2-细胞原胚、T-形原胚、多细胞原胚、小球胚及扩散至珠孔端的胚乳核。

The zygote , 2-cell proembryo , T-proembryo , multicellular proembryo , small globular embryo and endosperm nucleus diffusion to micropyle were observed in succession .

蓼型（Polygonum-type）胚囊大孢子母细胞减数分裂时，其珠孔端细胞壁出现胼胝质荧光，并逐渐扩展到整个细胞壁。

Polygonum-type & During the process of megasporocyte meiosis , callose occurs first in the wall of megasporocyte from micropylar end , then gradually envelops the whole cell .

结果表明，韭型（Alliumodorum-type）胚囊大孢子发生时，自大孢子母细胞的珠孔端细胞壁内出现胼胝质荧光，并逐渐扩展到整个细胞壁，中期Ⅰ至末期Ⅰ细胞壁呈现胼胝质荧光。

The results are as follows : Allium odorum-type & Callose first occurs in the wall of megasporocyte from the micropylar end , then gradually envelops the whole cell . Megasporocyte is surrounded by the wall with callose during metaphase ⅰ, anaphase ⅰ and telephase ⅰ .

珠孔区无珠孔领与孔盖的分化；

Micropylar collar and operculum are absent in micropylar region .

陆地棉珠孔的结构及花粉管在其中的生长途径

Structure of micropyle in Gossypium hirsutum and the pathway of pollen tube growth

（指植物的胚珠）珠孔完全直向顶点。

( of a plant ovule ) completely straight with the micropyle at the apex .

17～21小时，花粉管经珠孔到达胚囊；

17 ~ 21 hours the pollen tube reached the embryo sac through the micropyle ;

球形胚晚期吸器自珠孔端向合点端逐渐细胞化。

The haustorium cellularizated from the micropylar end to chalazal end at the later globular stage .

（指植物的胚珠）珠孔弯曲接近底部，几乎接触了干。

( of a plant ovule ) curved with the micropyle near the base almost touching its stalk .

成熟的胚囊是五核胚囊：由近珠孔端的卵细胞和两个助细胞以及两个中央极核细胞构成的。

The mature embryo sac was one with five nucleus , i.e. , egg apparatus and two-nucleus central cell .

合点珠孔对面的胚珠内结合珠被和珠心的一个区域。

The region of an ovule that is opposite the micropyle , where the integuments and nucellus are joined .

黄檗（芸香科）的珠孔塞和珠孔的形态发育及花粉管在子房室中的生长路径（英文）

Developmental Morphology of Obturator and Micropyle and Pathway of Poll Tube Growth in Ovary in Phellodendron amurense ( Rutaceae )

通过退化的助细胞进入胚囊，在珠孔端释两个精子。

And then , it enters the embryo sac by one degenerated synergid , releasing 2 sperms in the micropylar end .

胚根区有栅栏状细胞，珠孔区以上有薄壁细胞解体后形成的断裂层。

In radicle areas , there are palisade cells and a lucuna which located above micropyle and formed via knockdown parenchyma cells .

大孢子母细胞期间，其珠孔端沉积胼胝质，但并不完全包围之；

During meiosis , callose deposit on the micropylar end wall of the megasporocyte , but the cell was not enclosed by callose .

我们对黄檗胚珠的珠孔的形态发育研究显示，在不同的生殖时期，珠孔的结构会发生变化，在传粉时期它的结构显示不对称性。

Our investigations indicate that the structure of the micropyle changes with the different stages of the reproductive process , and becomes asymmetrical during pollination .

胚乳发育为核型，珠孔端胚乳细胞化，合点端保持游离核状态。

The endosperm development follows the nuclear type . The endosperm cells form at the micropylar end , and remain free nuclear phase at chalazal end .

胚珠发育过程中在胚囊内产生一横隔，将胚囊分为珠孔端室和合点端室，胚位于珠孔端室发育。

During the development a diaphragm is formed in the embryo sac and which divided the embryo sac into 2 chamber that is micropylar chamber and chalazal chamber .

胚珠发育异常一方面不能形成正常功能的胚囊（及雌配子体），另一方面不能在双受精过程中引导花粉管的正常延伸和进入珠孔，从而导致雌性不孕。

Abnormal ovule development could not form the normal functional sac , on the other hand could not guide the pollen tube extension and enter into the ovule .

在子房室内，沿珠柄侧的子房内壁生长至与胚珠珠孔相当部位时，花粉管离开子房壁进入珠孔，经珠心冠细胞之间隙抵达胚囊。

The pollen grain germinates on the stigma and the pollen tube grows along the hollow style canal into the ovary chamber at the funicle side and enters the micropyle .

胚囊母细胞发育排成直线形的四分体，其中靠合点端的一个胚囊细胞将成为有功能的大孢子，但靠珠孔端的其余胚囊细胞则不发育。

The megaspore mother cell develops into a linear tetral and the megaspore at chalazal end will become a functional megaspore but the rest at the microphyte end will not develop .

雌蕊3心皮3室，子房下位，中轴胎座，每室2倒生胚珠，厚珠心，双珠被，内珠被独自形成珠孔。

Its pistil consists of three carpels , the inferior ovary has three locules and each locule has two ovules which are anatropous on axile placenta . The ovule is bitegminous and crassinucellate .

花粉管通过柱头沟和花柱道时生长快，通过珠孔塞和珠孔以及珠柄时生长缓慢。

The growth rate of pollen tubes varied widely with the position of gynecium . The pollen tubes grew fast in the stigma canal and style canal , but slow in the obturator and micropyle .

大孢子母细胞继续生长，先在珠孔端出现一个较大的液泡，液泡随后移向合点端，细胞核移至珠孔端，此时环状内质网消失；

With the megasporocyte developing , a bigger vacuole appears in the micropyle end , then it migrating toward the chalazal end with the nucleus in the micropyle end , ringed ER disappears in this phase .

在胚囊发育过程中珠孔端的珠心组织退化，故成熟胶囊的卵器端直接与珠被和珠孔相接。

Owing to the degeneration of the nucellus at the micropyle pole during megagametogenesis , the egg apparatus pole of the mature embryo sac directly contacts with the integument and more or less penetrates into the micropyle .