葡萄两性花花蜜腺的发育解剖学研究

葡萄两性花的花蜜腺位于子房基部的花盘上,共5枚,呈椭圆形,与雄蕊相间排列,属于花盘蜜腺,蜜腺由表皮和泌蜜组织组成,缺乏维管束,表皮具薄的角质层,无气孔器,蜜腺原基由子房基部表层细胞恢复分裂能力形成,在蜜腺发育过程中,泌蜜组织的液泡规律 性变化和多糖动态变化均不明显,原蜜汁由子房维管束的韧皮部提供,蜜汁通过表皮细胞排出。     

‘辣椒95-1’保持系与雄性不育系花蜜腺的发育解剖学研究

采用扫描电镜和石蜡制片技术对'辣椒95-1'雄性不育系和同型保持系的花蜜腺及其发育过程进行了比较研究.结果表明:雄性不育系和同型保持系花蜜腺的位置、形态、结构及发育过程相似.辣椒的花蜜腺位于子房基部,围绕子房,属于子房蜜腺.蜜腺由分泌表皮和泌蜜组织组成.分泌表皮外覆角质膜,表皮无气孔分布,泌蜜组织为多层薄壁细胞.蜜腺由子房基部的外层表皮及其相邻的内侧细胞分裂、生长、分化而来.在花蕾膨大期,蜜腺细胞的细胞质较浓,已经开始积累淀粉粒和蛋白质;露冠期,分泌表皮和泌蜜组织的细胞质稀,淀粉粒和蛋白质大量增加;花蕾初放期,细胞质浓,淀粉和蛋白质的含量都非常高;盛花期,细胞质稀,液泡增大且数量增加,淀粉和蛋白质的量减少;败花期,细胞质稀,形成中央大液泡,淀粉重新积累.     

垂柳花蜜腺的发育解剖学研究

垂柳雌花蜜腺一枚,位于于房与花序轴之间,多呈扁平广卵形,由分泌表皮、泌蜜组织和维管束组成。雄花蜜腺呈基部相连的两枚突起,一枚位于花丝与花序轴之间,基部宽扁,上部棒状;另一枚位于花丝与苞片之间,棒状,仅由分泌表皮和泌蜜组织组成。雌、雄花蜜腺均起源于花托表面2—3层细胞。在蜜腺发育过程中,雌、雄花蜜腺泌蜜组织细胞的液泡发生规律性变化．雌花蜜腺为淀粉型蜜腺,而雄花蜜腺为非淀粉型蜜腺。雌、雄花蜜腺的原宜汁分别由蜜腺维管束韧应部或花丝维管束韧皮部提供,其蜜计最后均由分泌表皮细胞和变态气孔排出。     

小花糖芥花蜜腺的解剖学研究

小花糖芥（Erysimum cheiranthoides L.)花蜜腺位于雄蕊部花托上,仅有2枚侧蜜腺,属十字花科侧蜜腺类型中的侧半环亚型,其2枚密腺均由分泌表皮,产蜜组织和维管束组成。分泌表皮上有变态气孔器,产蜜组织中有维管束分布,属较进化的十字花科花蜜腺亚型类型。蜜腺原基是在花的各部分原基基本分化完成后,由花托表面及雄蕊基部区域的1－2层细胞,经反分化形成,在蜜腺发育过程中,蜜腺组织中的液泡和多糖物质都发生了有规律的变化,其原蜜汁在产蜜组织中加工合成,最后由表皮细胞和变态气孔泌出。     

四种蜜源植物花蜜腺的比较解剖学研究

草莓、漆树、芥菜和薄荷四种植物花蜜腺形态结构各异。草莓花蜜腺着生在花管内壁上属花被蜜腺。芥菜花蜜腺４枚,包括一对侧蜜腺和一对中蜜腺。漆树和薄荷的花蜜腺为花盘蜜腺,位于子房基部。四种花蜜腺都属结构蜜腺,其中仅芥菜的侧蜜腺组织中具维管束。它们在发育早期均无特殊的原始细胞,都由花器官表层细胞反分化形成原基,再发育成蜜腺。四种花蜜腺发育过程中细胞原生质体的液泡都表现出了规律性的消长变化。漆树和薄荷的花蜜腺具典型的淀粉动态变化,草莓的花蜜腺则属非淀粉型蜜腺;芥菜花蜜腺介于这两种类型之间。草莓和薄荷的花蜜由表皮细胞直接渗出。芥菜则气孔和表皮泌出兼备而漆树通过气孔泌蜜。     

荠的花蜜腺发育解剖学研究

荠(Capsella brsa-pastoris(L.)Medic.)的花蜜腺共4枚,都呈半圆形、绿色。蜜腺由分泌表皮、泌蜜组织和维管束组成,属于结构蜜腺。在花的各部分分化后,由花托表层细胞恢复分裂能力形成蜜腺原基。在蜜腺发育过程中,泌蜜组织的液泡和淀粉粒发生有规律的变化。荠的花蜜腺按其着生位置,属于花托蜜腺;其发生方式属居间生长,4枚蜜腺同步发生;根据其结构和泌蜜前后的多糖物质变化分析,其原蜜汁源于维管束的韧皮部,通过泌蜜组织输送到气孔下腔,然后由变态气孔排出。     

黄杨花蜜腺的形态解剖学研究

黄杨花单性,雌雄同株,雄花花蜜腺４枚,乳头状,着生于退化雌蕊子房顶部;雌花花蜜腺３枚,短柱状,位于３枚花柱之间。雌、雄花蜜腺均由分泌表皮、产蜜组织和维管束构成,在发育过程中产蜜组织细胞的液泡都发生有规律的变化。雌花蜜腺大,属非淀粉型蜜腺,泌蜜量大,蜜汁含糖分多,维管束中仅含韧皮部;雄花蜜腺小,属淀粉型蜜腺,泌蜜量小．蜜汁含糖量小,维管束由木质部和韧皮部构成。     

地椒花蜜腺发育的解剖学观察

通过显微和亚显微观察对地椒花蜜腺的发育进行了研究。地椒花蜜腺位于子房基部的花盘上,属于盘状蜜腺,新鲜时呈绿色。蜜腺由分泌表皮和泌蜜组织组成,分泌表皮为一层细胞,表皮细胞角质膜较厚,表皮上分布着大量的气孔器,气孔器突出于表面;泌蜜组织细胞多层。花盘中央有维管束通向子房,在维管束和泌蜜组织之间有４￣５层大型的薄壁细胞。蜜腺由花盘的表皮及其内侧相邻的细胞发育而来,在发育过程中,其细胞中的液泡和贮藏的淀粉     

芝麻菜花蜜腺的结构和发育研究

通过解剖镜观察、石蜡切片和薄切片等方法,对芝麻菜的花蜜腺的位置、形态、结构、发育过程及泌蜜前后组织化学变化进行了研究。芝麻菜花蜜腺4枚,分成两对,其中一对侧蜜腺较大,棱柱状,分别着生在外轮2个短雄蕊基部内侧的花托上,结构上由表皮、产蜜组织和维管组织构成;另一对中蜜腺较小,近棒状,分别着生在内轮4个长雄蕊外侧的花托上,结构上仅由表皮和产蜜组织构成。二者表皮细胞外都具角质层,且蜜腺产蜜组织细胞中只含少量的多糖物质。两类蜜腺的蜜汁均由变态气孔泌出体外。无论侧蜜腺还是中蜜腺,蜜腺原基皆是在雌、雄蕊已分化后,由花托相应位置表皮下的1～2层细胞分裂形成的。在蜜腺发育中,产蜜组织细胞在泌蜜前后不具明显的液泡变化。     

龙眼花蜜腺的发育解剖学研究

对龙眼(Dimocarpus longan Lour.)花蜜腺的形态结构、发育过程以及蜜腺的组织化学变化进行了较为系统的研究;对花蜜腺结构与泌蜜的关系、泌蜜方式、起源和系统演化等作了初步的探讨。结果表明：龙眼的花盘蜜腺位于花托上,呈环状环绕在雌雄蕊基部外围,花芽分化约30d,在雄蕊和花被之间的花托表面,蜜腺原基也开始形成,由花托表面2～3层细胞脱分化形成居间分生组织发育而来;龙眼花蜜腺由分泌表皮和产蜜组织构成,属结构蜜腺;分泌表皮角质层极薄,密布单细胞绒毛,未发现有气孔;产蜜组织由亚腺细胞、产蜜细胞、油细胞和维管束组成;在蜜腺发育过程中,产蜜细胞的液泡和多糖物质发生有规律的变化;蜜腺的原蜜汁来源于韧皮部,蜜汁经表皮角质层渗出。     

Ultrastructure of the Floral Nectary of Arabidopsis thaliana L. Prepared from High Pressure Freezing and Freeze Substitution

High pressure freezing and freeze substitution techniques were used to study the floral nectary of Arabidopsis thaliana L. focused on its ultrastmcture of mature nectary at pre-secretory, early secretory and heavy secretory stages. Questions of whether or not the transported vesicles fuse with the plasma]emma, and whether or not the "densely-stained cells" were comparable to companion cells during the secretory process were especially emphasized. The flowers of A. thaliana contained a pair of rather large lateral nectaries and 2 to 4 median ones. The median nectaries were situated at the bases of the two long stamens or between them while each of the. lateral ones was situated nearby each short stamen and between two petals. Before and during the secretion changes in the size of vacuoles and starch grains in the chloroplasts, the number of dictyosomes and endoplasmic mticulum and the distribution of mitechondria occurred before and during the stage of secretion. It appears that transported vesicles from the dictyosomes were transferred directly from one nectarfferous cell to another or to the exterior. They did not fuse with the plasmalemma when they left the cells. A great number of special "densely-stained cells" were different from the companion cells nearby the sieve elements. It was suggested that a tunnel be formed by these "densely-stained cells" connecting the stomata at the top of nectary leading the out-flow of nectar.     

油菜花蜜腺发育过程的超微结构变化与泌蜜机理的研究

油菜花蜜腺由２枚侧蜜腺和２枝中蜜腺组成,其基本结构类似。在蜜腺发育过程中,产蜜组织细胞内的内质网、高尔基体、质体和线粒体以及液泡都发生有规律变化。泌蜜前,细胞器的数量增加。其中,质体内积累淀粉,此过程与蜜腺内初皮部的分化并和线粒体的增加相关。泌蜜时,内质网数量增多,并产生小泡．小泡向质膜移动。泌蜜后,细胞液泡化,细胞器数量减少,细胞萎缩。根据观察结果分析,其原蜜汁来源于韧皮部,转运至产蜜组织细胞的质体、内质网和高尔基体内加工成蜜汁,最后通过胞吐和渗透相结合的方式泌出。     

Anatomical and ultrastructural changes of the floral nectary ofPisum sativum L. during flower development

Summary The floral nectary ofPisum sativum L. is situated on the receptacle at the base of the gynoecium. The gland receives phloem alone which departed the vascular bundles supplying the staminal column. Throughout the nectary, only the companion cells of the phloem exhibited wall ingrowths typical of transfer cells. Modified stomata on the nectary surface served as exits for nectar, but stomatal pores developed well before the commencement of secretion. Furthermore, stomatal pores on the nectary usually closed by occlusion, not by guard-cell movements. Pore occlusion was detected most frequently in post-secretory and secretory glands, and less commonly in pre-secretory nectaries. A quantitative stereological study revealed few changes in nectary fine structure between buds, flowers secreting nectar, and post-secretory flowers. Dissolution of abundant starch grains in plastids of subepidermal secretory cells when secretion commenced suggests that starch is a precursor of nectar carbohydrate production. Throughout nectary development, mitochondria were consistently the most plentiful organelle in both epidermal and subepidermal cells, and in addition to the relative paucity of dictyosomes, endoplasmic reticulum, and their associated vesicles, the evidence suggests that floral nectar secretion inP. sativum is an energy-requiring (eccrine) process, rather that granulocrine.Abbreviations ER endoplasmic reticulum - GA glutaraldehyde - SEM scanning electron microscopy     

Unusual transfer cells in the epithelium of the nectaries ofAsclepias curassavica L.

Summary The secretory cells of the nectaries ofAsclepias curassavica form a glandular epithelium in the inner parts of the stigmatic chambers. They resemble transfer cells in having many infoldings of the plasmalemma. The wall protuberances, however, are poorly developed and often lacking. The plasmalemma is highly convoluted and forms, in places, external compound membranes where the extracytoplasmic space is collapsed completely. Active glands contain dilated cisternae of the ER and large vesicles which are mainly associated with the cis face of the dictyosomes. In addition, small vesicles are observed in high number. It is discussed whether the secretion is granulocrine or eccrine and whether the enlargement of the plasmalemma is the cause or the consequence of the high secretory activity. After the secretory phase the outer peripheral part of the cytoplasm disintegrates. The remaining part of the protoplast is covered by a new plasmalemma.     

Floral nectar production and carbohydrate composition and the structure of receptacular nectaries in the invasive plant <Emphasis Type="Italic">Bunias orientalis</Emphasis> L. (Brassicaceae)

The data relating to the nectaries and nectar secretion in invasive Brassicacean taxa are scarce. In the present paper, the nectar production and nectar carbohydrate composition as well as the morphology, anatomy and ultrastructure of the floral nectaries in Bunias orientalis were investigated. Nectary glands were examined using light, fluorescence, scanning electron and transmission electron microscopy. The quantities of nectar produced by flowers and total sugar mass in nectar were relatively low. Total nectar carbohydrate production per 10 flowers averaged 0.3 mg. Nectar contained exclusively glucose (G) and fructose (F) with overall G/F ratio greater than 1. The flowers of B. orientalis have four nectaries placed at the base of the ovary. The nectarium is intermediate between two nectary types: the lateral and median nectary type (lateral and median glands stay separated) and the annular nectary type (both nectaries are united into one). Both pairs of glands represent photosynthetic type and consist of epidermis and glandular tissue. However, they differ in their shape, size, secretory activity, dimensions of epidermal and parenchyma cells, thickness of secretory parenchyma, phloem supply, presence of modified stomata and cuticle ornamentation. The cells of nectaries contain dense cytoplasm, plastids with starch grains and numerous mitochondria. Companion cells of phloem lack cell wall ingrowths. The ultrastructure of secretory cells indicates an eccrine mechanism of secretion. Nectar is exuded throughout modified stomata.     

Floral nectary and osmophore of <Emphasis Type="Italic">Epipactis helleborine</Emphasis> (L.) Crantz (Orchidaceae)

The analysis of flowers collected at different stages of anthesis provides strong evidence to conclude that the shell-shaped hypochile and the knobs of epichile form a nectary. The scent comes from the aromatic constituents of nectar and the epichile tissue and the apices of all tepals (osmophores). The comparison between pollinated and unpollinated flowers revealed that the anthesis of unpollinated flowers lasted up to the 16th day. The nectariferous secretory cells formed single-layered epidermis and several layers of underlying parenchyma built by small, isodiametric cells with thin walls and dense cytoplasm, relatively large nuclei, supplied by collateral vascular bundles. During the floral lifespan, the residues of secreted material were higher on the hypochile cells. The lipoid-carbohydrate material and lipid globules in the cell walls and in the cytoplasm were localised. The abundance of starch grains was observed at the beginning of anthesis and their gradual reduction during the flower lifespan. At the end of anthesis in unpollinated flowers, the lipoid-carbohydrate-phenolic materials have been demonstrated. The phenolic material was the same as in plastoglobuli. The features such as irregular plasmalemma, the secretory vesicles that fuse with it, fully developed dictyosomes, numerous profiles of ER indicate vesicle-mediated process of secretion. The substances could be transported by vesicles to the periplasmic space via granulocrine secretion and then to the external surface. Both micro-channels and slightly developed periplasmic space were visible in the hypochile epidermis. This is the first time for anatomical survey of secretory tissue in pollinated and unpollinated flowers of E. helleborine.     

Ultrastructure and Secretion of Extrafloral Nectaries of Plumeria rubra L.

Extrafloral nectaries situated on the adaxial side of the petiolebase are differentiated into a long head, comprising subepithelialground tissue surrounded by a layer of elongated palisade-likeepithelial cells and a short stalk from the nectary meristem.Many ultrastructural changes occur in epithelial and subepithelialcells of the nectary, from the young to secretory stages, suchas an increase in the amount of cytoplasm rich in mitochondriawith well developed cristae, rough endoplasmic reticulum (rER),smooth endoplasmic reticulum (sER) tubules and Golgi bodies.Plasmalemma invaginations with secretory vesicles occur longthe radial walls. Substantial amounts of secretory materialaccumulate in the gap between the radial walls and subcuticularspace, probably carried by the secretory vesicles from the cytoplasmat the secretory stage. Before cessation of secretion the cytoplasmbecomes vesiculated and the volume of the vacuome increases.At the post secretory stage, cytolytic processes and death ofcells occur. The subepithelial cells attain their maturity priorto epithelial cells. Histochemical localization reveals thepresence of lipids, proteins and insoluble polysaccharides withinthe epithelial cells and in the secretory material depositedin the subcuticular space as well as the gap between the radialwalls of the epithelial cells and outside the cuticle. Fine structure, nectary, Plumeria rubra, granulocrine secretion     

荇菜花蜜腺的发育研究

荇菜花蜜腺的发育过程可分为：起源期、生长期、分泌期以及泌蜜停止期等４个时期。荇菜的５枚花蜜腺均起源于子房基部的表皮及表皮内的２－４层细胞。这些细胞经反分化后分别成为蜜腺的原分泌表皮及原泌蜜组织,两部分细胞径不断地分裂分化,最冬成为成熟蜜腺。在蜜腺发育过程中,蜜腺的分泌表皮及蜜腺组织内的内质网、质体、线粒体、液泡等细胞器结构均发生了有规律的变化,内质网在蜜腺分泌期最为发达,且产生大量的分泌小泡。质体