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1.
对棉花种子萌发过程中子叶细胞内蛋白体的变化进行了详细的观察。干种子内存在仅由蛋白质基质组成无内含物的蛋白体,含有球状晶体的蛋白体和无含球状晶体和拟晶体的蛋白体。种子萌发过程中蛋白体逐渐液泡化,其降解方式可分为三种类型:(1)内部降解类型:(2)周边降解类型;(3)内部和周边同时降解类型。文中还一步进行了不同降解类型与酶的分布,蛋白体存在部位和萌发时间进程之间的关系。  相似文献   

2.
对燕麦糊粉细胞在种子萌发0,1,2,3,4,5,6,7天的亚显微结构进行了观察。重点观察了有关燕麦糊粉细胞内的蛋白体和糊粉细胞的胞壁在萌发过程中的变化情形。种子未萌发时,糊粉细胞内的蛋白体含有浓密的蛋白质基质和植酸钙镁以及蛋白-糖复合体两种内含体。种子萌发时,蛋白体内的蛋白质基质和植酸钙镁逐渐消失,而蛋白-糖复合体的消失则稍为缓慢。到萌发7天时,蛋白体都基本转化为液泡。糊粉细胞的胞壁在种子未萌发时具有内外两层壁结构。但在种子萌发时,外壁逐渐被水解而消失;但内壁则保持不变。文中还描述和讨论了有关糊粉细胞内壁和外壁的一些特性和功能。  相似文献   

3.
采用细胞化学方法 ,研究了黄瓜种子中贮藏Ca2 的分布特点及其在萌发过程中的变化动态。干种子的子叶细胞中贮藏有大量的蛋白体、油脂体 ,Ca2 沉淀颗粒大量分布于胞质、胞间隙以及细胞质膜上。大多数蛋白体中有 1至数个圆球形或椭圆体形含Ca2 的球状晶体。相比之下 ,胚芽和胚根细胞中Ca2 较少。种子萌发早期 ,子叶中的贮藏钙及晶体溶解释放出的Ca2 部分转运到生长发育中的胚芽和胚根中。随着萌发的继续 ,胚根和胚芽细胞中的Ca2 不会持续增多 ,反而下降  相似文献   

4.
黄瓜种子萌发过程中Ca^2+分布的变化   总被引:2,自引:0,他引:2  
吴慧涵  王建波 《植物生理学报》2001,27(2):141-144,T001,T002,T003
采用细胞化学方法,研究了黄瓜种子中贮藏Ca^2 的分布特点及其在萌发过程中的变化动态,干种子的子叶细胞中贮藏有大量的蛋白体,油脂体,Ca^2 沉淀颗粒大量分布于胞质,胞间隙以及细胞质膜上,大多数蛋白体中有1至数个圆球形或椭圆体形含Ca^2 的球状晶体,相比之下,胚芽和胚根细胞中Ca^2 较少,种子萌发早期,子叶中的贮藏钙及晶体溶解释放出的Ca^2 部分转运到生长发育中的胚芽和胚根中。随着萌发的继续,胚根和胚芽细胞中的Ca^2 不会持续增多,反而下降。  相似文献   

5.
采用细胞化学方法,研究了黄瓜种子中贮藏Ca2+的分布特点及其在萌发过程中的变化动态.干种子的子叶细胞中贮藏有大量的蛋白体、油脂体,Ca2+沉淀颗粒大量分布于胞质、胞间隙以及细胞质膜上.大多数蛋白体中有1至数个圆球形或椭圆体形含Ca2+的球状晶体.相比之下,胚芽和胚根细胞中Ca2+较少.种子萌发早期,子叶中的贮藏钙及晶体溶解释放出的Ca2+部分转运到生长发育中的胚芽和胚根中.随着萌发的继续,胚根和胚芽细胞中的Ca2+不会持续增多,反而下降.  相似文献   

6.
淀山湖3种沉水植物的种子萌发生态   总被引:30,自引:0,他引:30  
探讨淀山湖3种主要沉水植物(菹草、大茨藻和苦草)种子萌发与种皮、水温以及萌发基质之间的关系,种皮对咱子萌发的限制作用程度与种皮结构有关,种皮破裂后,发芽率和萌发速率均增高,水温对种子萌发具有一定的的促进作用,发芽率均以20℃时最大,但萌发速率却为28℃>20℃>10℃,不同沉水植物种子萌发的最适基质不同,苦草和菹草为水加土,而大茨藻则为土;单纯水中的发芽率和萌发速率均最低。  相似文献   

7.
棕果蝠取食对两种榕树种子萌发行为的影响   总被引:1,自引:0,他引:1  
在实验室利用聚果榕(Fieus racemosa)和对叶榕(Fieus hispida)成熟的果实饲喂笼养棕果蝠(Rousettus leschenaulti),比较了不同处理的3组种子的萌发行为:(1)棕果蝠粪便中的种子;(2)被吐出的果渣中的种子;(3)成熟果实中的种子(对照)。棕果蝠取食行为显著影响了两种榕树种子的萌发过程,3种不同处理的种子萌发过程及最终萌发率(GP)之间都存在显著的差异。聚果榕种子经过棕果蝠消化道后GP显著降低,而对叶榕种子的GP显著提高。棕果蝠粪便中的聚果榕种子萌发开始(GS)和最短萌发时间(Tmin)均比对照种子延迟了2d,但其粪便中的对叶榕种子G5比对照种子提前了1d,Tmin提前了2d;与之相似,前者种子萌发比果实中种子提前2d达到萌发总量的50%(T50),但后者没有改变T50。不同种榕果果渣中的种子萌发行为也有重大差异:聚果榕果渣中种子的Tmin和T50均比对照种子延迟1d,GS没发生改变;而对叶榕果渣中种子的Tmin比对照种子提前了3d,GS提前1d,T50没有改变。棕果蝠取食两种榕果后在飞行过程中排泄,进而有效的散布种子;而且通过消化明显改变了种子萌发行为,使种子萌发类型更为多样,增加了种子在不同时空条件下萌发的可能性。  相似文献   

8.
‘勐海大叶茶’种子萌发特性   总被引:1,自引:0,他引:1  
以大叶茶品种‘勐海大叶茶’ (Camellia sinensis var. assamica cv. Menghai Dayecha) 种子为材料,进行种子萌发特性的初步研究。研究发现,种皮对‘勐海大叶茶’种子的萌发存在一定的作用,含水量较高时,人为破除种皮有助于种子的萌发,随着含水量的降低,人为破除种皮反而降低了种子的萌发率。‘勐海大叶茶’种子的最适萌发温度为30℃,15℃以下时萌发率较低,容易发生低温伤害,变温处理对提高种子萌发率的效果不明显。基质对大叶茶种子萌发的影响不明显,四种不同种植基质条件下,种子的萌发率趋于相同水平,证明基质类型并非影响种子萌发的关键因子。  相似文献   

9.
非洲菊的组织培养与快速繁殖   总被引:7,自引:0,他引:7  
1植物名称非洲菊(Gerberajamesonii),又名扶郎花。2材料类别无菌种子萌发的幼苗。3培养条件(1)种子萌发培养基:1/2MS+0.7%琼脂(或脱脂棉);(2)诱导分化培养基:MS+6-BA1.5mp·L-1(单位下同)+IBA0.2;(3)芽增殖培养基:MS+6-BA0.5;(4)生根培养基:MS+NAA2。上述(2)、(3)、(4)培养基内琼脂均为0.7%,蔗糖3%,pH5.8~6.0。培养条件为室温和自然光照,种子萌发前为暗培养。4生长与分化情况4.1萌发种子用纱布袋包装,无菌…  相似文献   

10.
云南哀牢山徐家坝中山湿性常绿阔叶林动态和节律的研究   总被引:4,自引:0,他引:4  
根据多年定位观察资料,包括从组成种的种子萌发、幼苗生长及成年物种的生长规律和物候节律对湿性常绿阔叶林动态和节律的研究,结果表明:林地种子贮量、可萌发种子量和萌发种数,雨季大于旱季。幼苗生长雨季快于旱季。表明雨季是种子萌发、幼苗生长的最佳季节。立木生长是种间竞争、自我调控、自疏的过程。成年物种各物候期长、不明显与温带阔叶林各物候期短、明显不同,而开花、结果、落果终年进行与西双版纳季节雨林物候节律相似。三者的不同在于季节雨林春季(2~3 月)落叶,常绿阔叶林冬季(11~12 月)落叶,温带阔叶林秋季(9~10 月)落叶。依据物种物候节律特点及其对气候环境的反应区分出3 种生态物候型:1.暖温生态物候型(占总种数(50)的82% );2.温性生态物候型(占12% );3.温凉生态物候型(占0.6% )  相似文献   

11.
Membrane bound protein bodies (aleurone grains) are thought to be the main subcellular location of protein and mineral storage in seeds. In addition to structurally homogeneous proteinaceous matrix, protein bodies may contain protein crystalloids, electron–dense globoid crystals, electron–transparent soft globoids, and crystals of calcium oxalate. Protein crystalloids vary in shape, size and number. For example, cotyledon mesophyll cell protein bodies in the Cucurbitaceae generally contain protein crystalloids whereas those of Compositae and Cruciferae do not. Globoid crystals, which are rich in phytin, vary greatly in size and number per protein body. Some species have numerous small globoid crystals per protein body whereas others have one or two large globoid crystals per protein body. Phosphorus and various cations (K, Mg, Ca, Fe, Ba, Mn) located in globoid crystals can be studied with an energy dispersive X–ray (EDX) analysis system mounted on a transmission electron microscope. In some cases, cations such as Ca, Mn and Fe are specifically localized in globoid crystals of certain tissues or embryo regions. Further investigations may allow elemental composition of globoid crystals to be used in studies of systematics. Biref–ringent crystals, sometimes in the form of single large crystals but frequently in the form of druses, are present in protein bodies of some species. At least some endosperm protein bodies of all Umbelliferous species examined contain druse crystals. While seed protein bodies of relatively few species have been studied with electron microscopy, there are indications that protein bodies could be a useful character for studies in plant systematics.  相似文献   

12.
Protein bodies of pumpkin cotyledon cells were oval (about 10?7µm), and each was composed of a crystalloid, a globoidand proteinaceous matrix. They started to swell and fuse with1 day of imbibition. The proteinaceous matrix region expandedat the expense of crystalloids, and its electron density decreased.Finally, the protein bodies became central vacuoles includingmany small protein particles in about 8 days of germination. Fluorescent microscopy using antibodies raised against pumpkinseed globulin showed that fluorescence could not be observedin either protein bodies of ungerminated seeds or crystalloidsof germinating cotyledons, and only the proteinaceous matrixof germinating cotyledons became fluorescent. Probable causesof no fluorescence on crystalloids of seed globulin depositionwere considered. (Received November 9, 1979; )  相似文献   

13.
Protein bodies in the endosperm of castor bean seeds (Ricinus communis L.) contain phytin globoids and protein crystalloids embedded in an amorphous proteinaceous matrix. The protein bodies are apparently surrounded by a single membrane. The protein bodies were isolated by grinding and centrifuging in glycerol. Such isolated protein bodies were almost identical (after cytological fixation) to those observed in situ, except that the globoids were lost. However, membrane-like structures appear to have surrounded the globoids. Histochemical analysis of the isolated protein bodies showed that carbohydrates (glycoproteins) are localized only in the matrix region.  相似文献   

14.
A histochemical and ultrastructural study of yucca seed proteins   总被引:4,自引:0,他引:4  
Embryos and nutritive tissues in ungerminated Yucca seeds of 4 species contain many spherical bodies which stain positively for proteins. Two distinct morphological types were observed at both the light and electron microscope levels. A meshwork-type consists of electron-dense and electron-transparent regions in which are embedded slightly birefringent inclusions. The second type, named the core-type, consists of a core surrounded by a matrix in which the inclusions are embedded. A single unit membrane surrounds each protein body. Both types are present in the embryo while only the core-type protein body appears in the surrounding nutritive tissue (perisperm). All regions in each of the two protein body types, except the inclusions, stain histochemically for proteins. Seeds were planted at 2-day intervals and allowed to germinate through 14 days. As germination commences (day 0) protein bodies in the embryo begin to break down. By day 4 the bodies are depleted in embryos of 3 of the 4 species. About day 4, protein bodies in perisperm surrounding the embryo begin to break down and this process continues outward to the seed coat until day 14 when all seed proteins have disappeared. During germination the protein bodies in the embryo and perisperm of 3 species coalesce and then undergo breakdown. In a fourth species, there is no appreciable increase in size of the bodies, but an erosion of the periphery and possibly internally as well takes place, followed by ultimate dissolution.  相似文献   

15.
The ultrastructure and histochemistry of developing and mature cell inclusions in vegetative cells of Antithamnion defectum Kylin were examined. Those studied were chloroplast inclusions, cytoplasmic crystals and spherical bodies within the vacuole. Chloroplasts of mature vegetative cells contain an interthylakoidal, apparently noncrystalline deposit of undetermined chemical identity. The bodies are parallel to the long axis of the plastid, are square (0.13 μm) in cross-section, and up to 3 μm long. Spherical vacuolar bodies (0.5–1.5 μum diam) are formed during early stages of vacuole formation by accumulation of protein deposits in swelling endoplasmic reticulum (ER) cisternae. Swelling of smooth ER contiguous to the ER containing the deposits results in the vacuole enclosing the spherical bodies. In mature cells, vesicles appear to be secreted into the preformed vacuole. Cytoplasmic proteinaceous crystalloids develop without a bounding membrane and may serve as protein reserves.  相似文献   

16.
Protein bodies in embryonic axes of soybean seeds have inclusion structures containing phytin globoids. Biogenesis of the protein bodies during seed development was examined by transmission electron microscopy. Protein bodies in embryonic axes originated from central vacuoles. The central vacuole in embryonic axes subdivided into smaller vacuoles with internal membranous structure. Then the subdivided vacuoles were directly associated with rough endoplasmic reticulum (rER), and were filled with proteinaceous matrix from the peripheral region. The increase of matrix was simultaneous with accumulation of β-conglycinin estimated by SDS-polyacrylamide gel electrophoresis. Glycinin-rich granules that had been found in developing cotyledons were not observed in embryonic axes. After proteinaceous matrix filled the protein bodies, electron-transparent regions presumably surrounded by a single membrane appeared in the matrix. Phytin globoids were constructed in this internal structures of protein bodies as the final step of protein body formation.  相似文献   

17.
The endosperm of Washingtonia filifera consists of living cells with the same general cellular structure throughout the seed. The major storage reserves are carbohydrate, stored in the form of thickened walls; lipid, stored as numerous small lipid bodies which fill the cytoplasm; and protein, stored as large, but variably-sized, protein bodies. The protein bodies contain two types of inclusions: prismatically-shaped denser protein crystalloids and small crystalline deposits presumed to be phytic acid. The X-ray microanalysis shows these crystalline inclusions do contain P, Ca, Mg, and Fe. Protein bodies are positively stained with PAS. Nuclei are present in all cells, but stain very palely. Plastids and mitochondria are present, but infrequently seen. The plastids have few, poorly developed membranes. Endoplsasmic reticulum and dictyosomes are lacking. The cell wall is thick except in areas of pit fields and consists of three layers which differ in their staining with toluidine blue and in their ultrastructural characteristics: middle lamella, thickened outer wall, and thin inner wall. All wall layers are positively stained with PAS and calcofluor. Although general structural features of the endosperm in Washingtonia filifera are similar to those in date seeds, the composition of the wall polysaccharides and protein bodies appear to differ somewhat.  相似文献   

18.
Embryo protein bodies in S. lutescens have a uniform matrix and contain no globoid or crystalloid inclusions. Their digestion pattern consists of peripheral pitting, and the occurrence of vesicles along the margin of the formed invaginations suggests a controlled release mechanism. Protein bodies from both dormant and nondormant embryos were observed to be in all stages of digestion. Total protein decreases in both during the first 6 hr of hydration. Lipids do not decrease in hydrated dormant florets although a significant reduction does occur in germinating nondormant florets. Dormancy, therefore, may involve a mechanism that does not control processes already derived (protein body digestion) but does inhibit processes first begun by germination.  相似文献   

19.
Protein bodies were prepared from the cotyledons of pumpkin (Cucurbita sp.) seeds by employing a nonaqueous isolation method. Both light micrographic examination and the marker enzyme assays have shown that the isolated protein bodies were intact and contamination with other cell organelles or cytoplasmic components was negligible. A proteolytic enzyme catalyzing the limited hydrolysis of carboxymethylated γ′ chain of globulin was found to be present in the protein bodies. The specific activity in the protein body (18 units per milligram protein) was higher than that in the whole cell extract (13 units per milligram protein), indicating that the limited proteolytic enzyme was localized in the protein body.

After lysis of the protein bodies using hypotonic buffer solution, the suborganellar components (matrix, membranes, and crystalloids) were separated by sucrose density gradient centrifugation. The crystalloid was composed of only globulin, a major seed protein. The major proteins of matrix and membrane fractions were shown to have mol wt of approximately 10,000. About 90% of the limited proteolytic activity was found in the matrix region.

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