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1.
蚕豆胚珠发育过程中淀粉动态的观察   总被引:4,自引:0,他引:4  
蚕豆胚珠发育过程中淀粉动态变化如下:1.发育早期,整个胚珠中未见淀粉粒。其后首先在合点区出现淀粉,而后从合点向珠孔逐渐扩大分布范围。2.珠心和内、外珠被中均含有淀粉粒,尤以内珠被的淀粉增长迅速,数量多、个体大。受精后,内珠被解体,淀粉出现在外珠被细胞中,推测营养物质可通过整个胚囊表面进入其中。3.合点与胚囊之间的珠心细胞特化或长形。可能有助于营养物质进入胚囊。4.功能大孢子中贮存丰富的淀粉粒,它和珠心细胞一起是胚囊发育时的营养来源。5.卵细胞受精后,所含淀粉粒的数量和大小明显增长,随着合子和胚细胞的分裂,其中贮存的淀粉逐渐被消耗,到多细胞球形胚时完全消失。6.胚乳核周围始终未出现淀粉粒。7.胚器官分化之后,子叶和胚轴等处逐渐出现淀粉粒,其中生长活跃的结构如生长点、维管束等不贮存淀粉。8.子叶中的淀粉粒含量迅速增加,颗粒特大,是种子内营养物质的最终贮存场所。  相似文献   

2.
槐(Sophora japonica L.)种子发育过程中,子叶细胞大量合成和积累储藏物质,光镜和电镜下用组织化学观察到开花后30d,叶肉细胞高度液泡化,其中分而着大量的质体、粗面内质网、一些线粒体的小脂体。淀粉开始积累。开花后60d,淀粉和脂体不断长大,数量明显增多,液泡中蛋白体开始形成。从花后90d开始,液泡中有大量蛋白体形成且不断长大,有些蛋白体变得不规则形。至种子成熟期,叶肉细胞几乎完全被  相似文献   

3.
用酶解法解离受精后5 d 和20 d 的红莲( Nelumbo sp.) 子叶细胞,应用冷却型科学级电荷偶联装置(CCD) 摄像式显微荧光影像系统对单个5 d 细胞和20 d 细胞的DNA、RNA和总蛋白相对含量进行了相关测量。实验结果表明:20 d 细胞DNA成为多倍化,为4C~8C水平。视窗分析表明:同一4CDNA 视窗中,20 d 细胞比5 d 细胞的RNA和总蛋白含量增加11 倍以上。20 d 细胞的两个DNA视窗(4C和8C) 中,随着DNA倍性的增高,RNA 和总蛋白含量也以大致上相应的倍数增高。这些数据表明:红莲子叶贮存蛋白的大量积累既与DNA 倍性有关,又与发育过程中贮存蛋白亚基基因选择性的表达有关  相似文献   

4.
以萌发后不同时期的大豆子叶为材料,通过普通光镜和荧光显微镜观察,分析了不同时期子叶细胞的结构变化及子叶细胞内蛋白质和淀粉含量的组织化学变化.结果表明,随着种子萌发时期的延长,子叶细胞内的蛋白质和淀粉含量逐渐减少,在子叶衰老过程中,细胞内蛋白质首先消耗殆尽,淀粉的消耗速度较蛋白质慢;大豆子叶细胞在萌发后第18天时出现典型的植物编程性死亡的形态学特征,子叶细胞内营养物质的消耗诱发子叶细胞发生细胞凋亡.  相似文献   

5.
甘薯块根生长及其淀粉体发育过程的解剖结构特征   总被引:1,自引:0,他引:1  
为了探明甘薯块根的生长及其淀粉体的发育规律,该试验以甘薯品种‘徐薯22’为材料,采用树脂半薄切片等方法对甘薯块根的生长及其淀粉体的发育进行观察研究。结果表明:(1)甘薯块根完成初生生长的时间短,块根初生结构由表皮、皮层和中柱构成,块根横截面上皮层所占比例比中柱大。(2)甘薯移栽后10 d块根开始次生生长,次生生长形成维管形成层和木栓形成层;随着块根次生生长,位于次生木质部分散导管周围的薄壁细胞脱分化,通过平周分裂产生副形成层;维管形成层、木栓形成层和副形成层的共同作用使块根快速膨大。(3)淀粉体在块根进入次生生长时首先在皮层细胞产生,随后大量出现在次生生长产生的薄壁细胞中,块根中淀粉体的发生及发育总体上表现出由外向内的顺序。(4)块根薄壁细胞中的淀粉粒有单粒和复粒两种类型;块根生长早期,薄壁细胞中主要以复粒淀粉为主,生长后期主要以单粒淀粉为主;块根生长过程中,包含复粒淀粉的淀粉体可通过分裂形成包含单粒淀粉的淀粉体。(5)淀粉可在块根生长的整个时期积累,其中以块根生长中期积累速度最快。  相似文献   

6.
高,低蛋白含量的大豆种子贮藏蛋白积累的比较研究   总被引:4,自引:0,他引:4  
利用SDS-PAGE及电子显微镜等技术比较分析和观察了两个大豆品种(Glycine m ax(L.) Merr.)种子贮藏蛋白积累的差异。结果表明,在子叶发育过程中,蛋白含量高(45% )的“公交8059-3”比蛋白含量低(35% )的“GD-1515”蛋白含量高,且增长速率较快;蛋白质及7S和11S亚基积累的时期较早,尤其是7S的β亚基。电镜观察表明“公交8059-3”蛋白质在液泡中的积累,前期与“GD1515”相似,中期以后的液泡中,蛋白体占整个细胞的比例均高于“GD1515”。这表明:大豆蛋白含量的差异有其生化及结构上的基础  相似文献   

7.
用DNA银染法研究传染性软疣病毒的形态发生发育过程   总被引:2,自引:0,他引:2  
用DNA银染技术显示了传染性软疣病毒(MCV)形态发生发育及其过程中DNA的变化。结果显示:在被感染的皮肤表皮细胞内都有一个大小及构型不同的银染区(病毒工厂)。MCV的发生发育均在银染区内而不在胞质区内。其发生过程是先在细胞一侧的胞质内复制合成病毒DNA等物质,形成中等密度的银粒大小不等的银染区(病毒前包涵体区),然后在其中形成致密的细粒状银染区(病毒前基质区),接着在后者的周围出现弧形的粗粒银沉淀(初期MCV的外膜),逐渐分割包围病毒前基质而形成初期MCV。在发育过程中,初期MCV的外膜、基质,核心外膜及核心均经过一系列的形态变化。侧体是中期MCV向成熟期发育中出现的暂时性结构,其本质为含DNA成分的病毒基质。本研究提示:MCV的DNA物质进入皮肤表皮细胞后能大量复制,合成大量的病毒蛋白质,自主地装配成完整的初期MCV,后者有独特的形态发育过程。  相似文献   

8.
小麦胚乳细胞的分离及其淀粉体的计数   总被引:13,自引:1,他引:12  
IsolationofEndosPermCellsandCalculationofTheirStarchGrainsinWheatPlants小麦胚乳重量占籽粒重的90/以上.胚乳细胞的分裂数目及其淀粉体的发育状况决定着籽粒的重量和品质卜‘。在胚乳细胞增殖期,如能增加胚乳细胞的分裂速度.就能增加产量k‘.因而分离胚乳细胞,观察胚乳细胞的发育技术与方法受到人们的重视)-’‘’。前人对胚乳细胞的计数大致有以下几种方法:()根据胚乳体积与胚乳细胞体积之比推算”‘;(2)用纤维素酶分解胚乳.计数单位酶液中的细胞数)‘’;(3)先用纤维素分解胚乳后再用淀粉酶解离细胞中的淀粉.…  相似文献   

9.
在花生(Arachis hypogaea)荚果发育过程中,子叶细胞的超微结构和脂酶活性皆发生了显著变化。子叶生长初期,缅胞中质体较多,并不断形成淀粉粒;脂酶活性低,脂体和蛋白体很少。子叶发育中期,子叶细胞质中出现大量体积较大的脂体,液泡中的蛋白体不断形成和增大,而且细胞质、内质网、蛋白体外膜、细胞质膜和细胞间隙上皆显示较强的脂酶活性。子叶发育后期,脂体数量不再增加,但体积略有增大,间质透明度也有提高;蛋白体增大较小,但数量却进一步增多;细胞质中仍显示较强的脂酶活性。至末期时,蛋白体形态变得不规则,甚至出现部分解体,其基质充挤脂体间隙;细咆中的脂酶活性减弱。研究表明,花生脂体起源于细胞质,蛋白体起源于液泡,子叶油分和蛋白质的积累足体内脂体和蛋白体不断发育的结果,细胞中脂酶活性的变化可能与脂体发育有关。  相似文献   

10.
莲幼胚子叶细胞造淀粉体DNA的动态变化   总被引:5,自引:0,他引:5  
莲(Nelumbo nucifera Gaertn.)幼胚子叶细胞造淀粉体和分离的造粉质体上均呈现强烈的 Feulgen 反应物质。经 DNA 酶处理后,在子叶细胞造淀粉体上呈 Feulgen 负反应。将分离的造粉质体用特异性的 DNA 荧光染料 DAPI 染色,造粉质体显示蓝色的荧光。实验证明,莲幼胚子叶细胞随着发育时期的增长,造粉质体 DNA 的含量逐渐增加,显示出有规律的动态变化过程。在电镜下观察,造粉质体 DNA 区域外无膜结构存在,故具有原核生物的特征。这种质体 DNA 的纤维丝直径大约为25。  相似文献   

11.
陈建敏  孙德兰 《植物学报》2005,22(5):541-548
莲子叶细胞中储存了丰富的营养物质, 主要为蛋白质、淀粉和淀粉质体DNA。这些贮藏物质为种子萌发和幼苗的生长提供必需的能量和养料。通过组织化学和显微镜观察, 研究莲从种子萌发到植株生长至具有4个节时, 子叶中贮藏物质消耗的全过程。在此过程中, 子叶中的贮藏物质不断降解,营养物质发生转运。蛋白体首先发生降解, 其大量降解主要发生在幼苗三叶期。淀粉质体降解时会聚 集成团, 之后体积逐渐减小, 最后完全降解。种子萌发后65天是子叶贮藏物质消耗末期, 淀粉质体DNA的含量比萌发后20天的三叶期明显减少。细胞壁的形态结构发生多种形式的变化, 细胞壁发生的这些变化与子叶细胞间物质的运输有关。含多糖的球形颗粒通过维管束在子叶中运输。  相似文献   

12.
莲种子萌发和幼苗生长时期营养物质的代谢变化   总被引:2,自引:1,他引:1  
莲子叶细胞中储存了丰富的营养物质,主要为蛋白质、淀粉和淀粉质体DNA.这些贮藏物质为种子萌发和幼苗的生长提供必需的能量和养料.通过组织化学和显微镜观察,研究莲从种子萌发到植株生长至具有4个节时,子叶中贮藏物质消耗的全过程.在此过程中,子叶中的贮藏物质不断降解,营养物质发生转运.蛋白体首先发生降解,其大量降解主要发生在幼苗三叶期.淀粉质体降解时会聚集成团,之后体积逐渐减小,最后完全降解.种子萌发后65天是子叶贮藏物质消耗末期,淀粉质体DNA的含量比萌发后20天的三叶期明显减少.细胞壁的形态结构发生多种形式的变化,细胞壁发生的这些变化与子叶细胞间物质的运输有关.含多糖的球形颗粒通过维管束在子叶中运输.  相似文献   

13.
It was first shown that the amyloplasts in young cotyledon cells of lotus (Nelumbonucifera Gaertn.) and the isolated amyloplasts stained with Feulgen reaction and treated by DNase, had Feulgen-positive reaction and Feulgen-negative reaction respectively. The isolated amyloplasts stained with DAPI demonstrated blue fluorensence. Some experiments proved that DNA content in the amylopasts increased gradually with the development of cotyledon, showing the dynamic change of DNA in the amyloplasts. Electron microscopic observation revealed that there was no membrane surrounding the DNA region of the amyloplasts illustrating the characteristic of its protokaryotic organisms. The DNA fibrils were about 25A in diameter.  相似文献   

14.
Amyloplasts and cytoplasmic ribosomes in cotyledon cells of lotus (Nelvmbo nucifeva Gaertn. ) have been observed on the basis of morphology. Isolation of these ribosomes by centrifugation through 30% to 55% (W/V) sucrose density gradient resulted in three bands of amyloplasts ribosomes and four bands of cytoplasmic ribosomes. The authors used these ribosomes bands for SDS-PAGE electrophoresis to analyse ribosomes of proteins. The patterns of SDS-PAGE between cytoplasmic ribosomes of proteins and amyloplasts ribosomes of proteins were different. The amyloplasts ribosomes of proteins showed 26 kD and 23 kD bands, and the cytoplasmic ribosomes of proteins showed 65 kD band. The analysis of electrophoretic patterns of the cytoplasmic ribosomes of proteins showed that there was a newly synthesized ribosomes protein with 19 kD molecular weight in 18 to 20 days after fertilization.  相似文献   

15.
SMITH  D. L. 《Annals of botany》1973,37(4):795-804
During the cell-division period of cotyledon development inPisum arvense L. cell volume increases slightly but nuclearvolume shows little variation and the DNA content remains atthe 2C to 4C level. During the main period of cell expansionthere is a close correlation between cell volume, nuclear volume,and nuclear DNA content, the nuclei of the largest storage cellsfinally attaining the 64C level. The rate of RNA synthesis increasesseveral days after the increase in DNA has begun and at thesame time accumulation of reserve protein and starch begins.RNA and starch synthesis apparently cease some time before maturationbut protein synthesis continues until the seeds are ripe. Cotyledondevelopment was found to comprise two distinct phases: an initialphase of cell division and differentiation during which DNA,RNA, and protein per unit volume of cell decline; and a phaseof reserve accumulation in which DNA per unit volume of cellremains constant but RNA and protein per unit volume increase,starch synthesis is initiated, and all the cotyledon cells assumethe properties of storage cells.  相似文献   

16.
This study aimed to analyze male gamete behavior from mature pollen to pollen tube growth in the bicellular pollen species Alstroemeria aurea. For mature pollen, pollen protoplasts were examined using flow cytometry. The protoplasts showed two peaks of DNA content at 1C and 1.90C. Flow cytometry at different developmental stages of pollen tubes cultured in vitro revealed changes in the nuclear phase at 9 and 18 h after culture. Sperm cell formation occurred at 6–9 h after culture, indicating that the first change was due to the division of the generative cells into sperm cells. After sperm cell formation, the number of vegetative nucleus associations with sperm cells showed a tendency to increase. This association was suggested as the male germ unit (MGU). When sperm cells, vegetative nuclei, and partial MGUs were collected separately from pollen tubes cultured for 18 h and analyzed using a flow cytometer, the sperm cells and vegetative nuclei contained 1C DNA, while the DNA content of partial MGUs was counted as 2C. Therefore, the second change in the nuclear phase, which results in an increase in 2C nuclei, is possibly related to the formation of MGUs.  相似文献   

17.
M. F. le Gal  J. N. Hallet  L. Rey 《Protoplasma》1984,120(1-2):113-122
Summary The relationship between the DNA and reserve protein contents have been investigated in the cells of mature cotyledons ofPisum sativum. The study was made on two seeds chosen, on preliminary analysis, as having a markedly different protein content per cotyledon. The seed with the higher protein content was of theCameor variety, the other was of theAmino variety. The DNA content per cell was measured with a scanning microspectrophotometer and the protein content per cell using morphometric methods. In both seeds, nuclei of the storage parenchyma were polyploid in a range from 8 to 64 C levels, but the average DNA content per cell was higher in the Cameor specimen. The protein content also, whether expressed per unit of protoplasm or per cell, was always higher in the Cameor seed. The greater protein content of this seed was due to a higher content of protein per cell. In both seeds the level of ploidy and the reserve protein content per cell increased in the same way from the peripheral zone to the centre of the cotyledon. A high positive correlation was found for the two seeds between the DNA content and the protein content per cell.  相似文献   

18.
通过向蚕豆叶片饲喂~(14)CO_2,应用液闪和显微放射性自显影技术表明标记同化物经叶脉和果荚韧皮部筛管快速运输至蚕豆种皮。种皮吸收营养、生长,后期逐步降解、供养子叶。种皮内的两类维管束系统同时输送营养并卸出到种皮内侧的质外体空间里。种皮里的反向维管束韧皮部卸出以共质体方式为主。并提供养分供种皮生长,而大部分的同化物由正向完整维管束韧皮部的筛分子一传递细胞进行质外体方式卸出。膨大中的子叶在早期即已成为生理上十分活跃的库。它对标记同化物的摄入随时间进程而急剧上升。  相似文献   

19.
Resistance of wild and cultivated rice bean (Vigna umbellata [Thunberg] Ohwi and Ohashi) to three bruchid species, Callosobruchus chinensis L., Callosobruchus maculatus F., and Callosobruchus analis F., was evaluated. All but three accessions of cultivated, and all wild rice bean accessions tested, exhibited complete resistance to all three bruchid species. Rice bean seeds with seed coat removed also showed complete resistance to the three bruchid species. Results indicate that physical attributes and/or chemical(s) present in the seed coat of rice bean are not the main factors responsible for resistance. Feeding tests were performed by using artificial beans prepared with varying proportions of rice bean (resistant) and azuki bean (susceptible) flour. Number of bruchid adults that emerged decreased, and larval developmental period (days) was extended, when artificial beans with an increasing proportion of rice bean flour were used. These tests revealed that a chemical compound(s) contained in the cotyledon of rice bean has an inhibitory effect on the growth of these bruchid species. The results also indicate that the chemical(s) in rice bean cotyledon is most effective against C. maculatus.  相似文献   

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