scholarly journals Flowering biology and structure of floral nectaries in Galanthus nivalis L.

2016 ◽  
Vol 85 (1) ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Mirosława Chwil
Keyword(s):  
Breeding System ◽  
Nectar Secretion ◽  
Floral Nectary ◽  
Transmission Electron ◽  
Cuticular Ornamentation ◽  
Self Compatibility ◽  
Floral Nectaries ◽  
Galanthus Nivalis ◽  
Light Fluorescence ◽  
Parenchymal Cells

In Poland <em>Galanthus nivalis</em> L. is partially protected. The flowers of this species are one of the first sources of nectar and pollen for insects from February to April. The aim of this study was to present the flowering biology as well as the topography, anatomical, and ultrastructural features of the floral nectary. The flower lifespan, the breeding system, and the mass of pollen and nectar produced by the flowers were determined. Examination of the nectary structure was performed using light, fluorescence, scanning and transmission electron microscopy. The flower of <em>G. nivalis</em> lives for about 30 days. The stamens and pistils mature simultaneously and during this time nectar is secreted. The anthers of one flower produced the large amount of pollen (4 mg). The breeding system of <em>G. nivalis</em> was found to be characterized by partial self-compatibility, outcrossing, and xenogamy. The nectary is located at the top of the inferior ovary. The nectary epidermal cells are characterized by striated cuticular ornamentation. Initially, the secreted nectar formed vesicle-like protuberances under the cuticle. The epidermal and parenchymal cells contain numerous plastids, mitochondria, dictyosomes, ER cisterns, and vesicles fused with the plasmalemma, which indicates granulocrine nectar secretion.

scholarly journals Structure of floral nectaries in Aesculus hippocastanum L.

2017 ◽  
Vol 76 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Mirosława Chwil
Keyword(s):  
Electron Microscopy ◽  
Morphological Diversity ◽  
Aesculus Hippocastanum ◽  
Vascular Bundles ◽  
Fluorescence And Electron Microscopy ◽  
The Family ◽  
Floral Nectaries ◽  
Light Fluorescence ◽  
Parenchymal Cells ◽  
First Time

Abstract Representatives of the family Sapindaceae exhibit high morphological diversity of the nectary structure. The present paper shows for the first time the results of micromorphological, anatomical, and ultrastructural analyses of floral nectaries in Aesculus hippocastanum. We have also described the forage and signal attractants of these flowers, which are important for the ecology of pollination. Using light, fluorescence, and electron microscopy, we demonstrated that the A. hippocastanum nectary forming a lobed disc is histologically differentiated into the epidermis with stomata, nectariferous parenchyma, subglandular parenchyma, and vascular bundles reaching the basal part of the nectariferous parenchyma. The use of histochemical assays revealed the presence of insoluble polysaccharides, lipids, terpenoids, and polyphenols including coumarins in the nectary tissues. Nectar is exuded onto the nectary surface via stomata and the permeable cuticle. As indicated by the observation of the ultrastructure of the nectary cells, transport of pre-nectar into parenchymal cells may proceed via the symplast and apoplast. We have also demonstrated that nectar transfer outside the protoplasts of parenchymal cells has a character of granulocrine secretion. A. hippocastanum flowers produce nectar abundantly; one flower secreted on average 2.64 mg of nectar and the concentration of sugars in the nectar was 33%.

scholarly journals Comparison of features of the epidermis and the size of the floral nectary in four species of the genus Cotoneaster Med.

2012 ◽  
Vol 64 (4) ◽  
pp. 47-58 ◽  
Author(s):  
Mirosława Chwil ◽  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Stomatal Density ◽  
Epidermal Cells ◽  
Floral Nectary ◽  
Cuticular Ornamentation ◽  
Floral Nectaries ◽  
Nectariferous Tissue ◽  
Nectar Flow ◽  
Scanning Electron

The investigations involved four species of the <i>Cotoneaster</i> genus: <i>C. divaricatus</i>, <i>C. horizontalis</i>, <i>C. lucidus</i>, <i>C. praecox</i>, which are commonly grown for decorative purposes. In Poland, these plants bloom in May and June and are a source of abundant spring nectar flow for insects. The floral nectaries of the above-mentioned species were examined using stereoscopic, light, and scanning electron microscopy in order to assess their size and epidermal microstructure. In the plants studied, the upper part of the hypanthium is lined by nectariferous tissue. The nectaries in the four species vary in terms of their sizes. Nectar is secreted onto the surface of the epidermis through anomocytic, slightly elongated or circular stomata. The largest stomata on the nectary epidermis were found in the flowers of <i>C. horizontalis</i>, and the smallest ones in <i>C. divaricatus</i>.Their size and location in relation to other epidermal cells were taxon-specific. The highest density of stomata in the nectary epidermis was found in <i>C. divaricatus</i> (205 per mm<sup>2</sup>), whereas <i>C. horizontalis</i> flowers exhibited the lowest (98 per mm<sup>2</sup>) stomatal density. The cuticular ornamentation on the nectary epidermis surface was diverse. The stomatal indices calculated for the nectary epidermis were considerably lower than for the leaves in the particular species.

scholarly journals Structure of trichomatous nectaries in flowers of Lonicera kamtschatica (Sevast.) Pojark.

2012 ◽  
Vol 61 (1) ◽  
pp. 13-26 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Małgorzata Bożek
Keyword(s):  
Electron Microscopy ◽  
Corolla Tube ◽  
Nectar Secretion ◽  
Apical Portion ◽  
Transmission Electron ◽  
Secretory Tissue ◽  
Floral Nectaries ◽  
Subcuticular Space ◽  
Lateral Walls ◽  
Scanning Electron

The structure of the floral nectaries of <i>Lonicera kamtschatica</i> was examined using light microscopy, scanning electron microscopy and transmission electron microscopy. Nectariferous tissues are located in the lower portion of the corolla tube. It was found that the secretory tissue of the nectary was composed of two layers of epidermal formations: short papillae and about 3x longer unicellular trichomes. They cover the adaxial surface of a small spur. Nectar secretion takes place through the apical portion of the trichomes and papillae. The cell wall of the upper part of the trichome has protuberances participating in nectar transfer to the subcuticular space which reaches large dimensions. The lateral walls of the trichomes are saturated with cutin. The papillae have much thicker walls than the trichomes. In the papillae, there are no wall protuberances. Less secretion accumulates in the subcuticular cavities of the papillae than in the trichomes.

scholarly journals Anatomy and ultrastructure of floral nectary of lnula helenium L (Asteraceae)

2011 ◽  
Vol 76 (3) ◽  
pp. 201-207 ◽  
Author(s):  
Aneta Sulborska ◽  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Secretory Cells ◽  
Secretory Vesicles ◽  
Nectar Secretion ◽  
Golgi Bodies ◽  
Floral Nectary ◽  
Granular Cytoplasm ◽  
Inula Helenium ◽  
Modified Stomata ◽  
Floral Nectaries ◽  
Anatomy And Ultrastructure

Floral nectaries of <em>Inula helenium</em> L. only occurred in disc florets and were situated above the inferior ovary. The shape of the investigated glands (five-armed star with rounded tips and deep incisions - observed from above) clearly differed from the shape of the nectaries of other <em>Asteraceae</em>, also the height of nectary was much lower (129 µm). The glandular tissue of the nectaries of elecampane was composed of a single-layered epidermis and 5--9 layers of secretory cells. Nectar was released through modified stomata, mainly arranged in the top part of the gland. The secretory cells were characterised by granular cytoplasm and the presence of a large, often lobate, cell nucleus. In the cytosol, numerous amoeboid plastids, mitochondria, Golgi bodies and ribosomes were present. In small vacuoles, myelin-like structures, fibrous material and vesicles with the content of substances which can be secretion, were observed. The plastid stroma showed different electron density and the presence of internal tubules and plastoglobules. Vesicular extensions forming bright zones were visible between the membranes of the nuclear envelope. Adjacent to the plasmalemma, as well as between the plasmalemma and the cell wall, secretory vesicles occurred, indicating the granulocrine mechanism of nectar secretion.

scholarly journals Anatomy of the floral, bract, and foliar nectaries of Triumfetta semitriloba (Tiliaceae)

2005 ◽  
Vol 83 (3) ◽  
pp. 279-286 ◽  
Author(s):  
Carlos André Espolador Leitão ◽  
Renata Maria Strozi Alves Meira ◽  
Aristéa Alves Azevedo ◽  
João Marcos de Araújo ◽  
Kellen Lagares Ferreira Silva ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Type A ◽  
Structural Features ◽  
Floral Bract ◽  
Secretory Structures ◽  
Floral Nectary ◽  
Foliar Anatomy ◽  
Weedy Species ◽  
Floral Nectaries

Triumfetta semitriloba Jacq. (Tiliaceae) is a tropical weedy species with floral nectaries and glands located at the margins of the leaves. The objectives of this work were to describe the anatomy of these secretory structures and to analyze their exudates. Sucrose, glucose, and fructose were identified in the product released by these secretory structures, characterizing them as nectaries. The nectaries of T. semitriloba are of a specialized type; a secretory epidermis comprised of pluricellular and multiserial nectariferous trichomes covers a nectariferous parenchyma, vascularized by phloem and xylem. A mass of phenolic compounds occurs in the head cells of the nectariferous trichomes of the foliar and bract nectaries; however, it is absent in trichomes of the floral nectary. The leaf and bract nectaries differed from those from flowers in their length and diameter. Structural features of the nectaries of T. semitriloba are typical of other taxa of the Malvales.Key words: foliar anatomy, histochemistry, Malvales, nectaries, Tiliaceae, Triumfetta semitriloba.

scholarly journals Histopathology of Colletotrichum gloeosporioides on guava fruits (Psidium guajava L.)

2013 ◽  
Vol 35 (2) ◽  
pp. 657-664 ◽  
Author(s):  
Sylvia Raquel Gomes Moraes ◽  
Francisco André Osama Tanaka ◽  
Nelson Sidnei Massola Júnior
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Colletotrichum Gloeosporioides ◽  
Psidium Guajava ◽  
Mature Stage ◽  
Guava Fruit ◽  
Transmission Electron ◽  
Colonization Process ◽  
Parenchymal Cells ◽  
Appressoria Formation

Anthracnose, caused by Colletotrichum gloeosporioides, produces brown lesions on guava fruits, causing severe losses on postharvest. In this study, the infection and colonization of guava fruits by C. gloeosporioides has been examined using scanning and transmission electron microscopy. Fruits at the physiologically mature stage were inoculated with a 10(5) conidia/mL spore suspension. Afterward, fruits were incubated at 25 °C in a wet chamber for periods of 6, 12, 24, 48, 96 and 120 h to allow examination of the infection and colonization process. Conidia germination and appressoria formation occurred six hours after inoculation (h.a.i). Penetration occurred directly via penetration pegs from appressoria, which penetrated the host cuticle 48 h.a.i. Notably, the appressoria did not produce an appressorial cone surrounding the penetration pore. Infection vesicles were found in epidermal cells 96 h.a.i. The same fungal structures were found in epidermal and parenchymal cells of the host 120 h.a.i. Colonization strategy of C. gloeosporioides on guava fruit was intracellular hemibiotrophic.

Adaptive response of extreme epiphyte Tillandsia species (Bromeliaceae) is demonstrated by different sexual reproduction strategies in the Brazilian Chaco

2019 ◽  
Vol 192 (4) ◽  
pp. 840-854
Author(s):  
Aline C Gomes ◽  
Bruno H S Ferreira ◽  
Camila S Souza ◽  
Luan M M Arakaki ◽  
Camila Aoki ◽  
...  
Keyword(s):  
Breeding System ◽  
Reproductive Strategies ◽  
Extreme Environments ◽  
Extreme Environment ◽  
Floral Biology ◽  
Reproduction Strategies ◽  
Pollen Vectors ◽  
Self Compatibility ◽  
Floral Visitors ◽  
Selection For

Abstract Some epiphytes are adapted to extreme environments with the ability to survive drought as a result of their morphological (xeromorphism), anatomical (foliar trichomes or scales) and physiological features. In contrast to vegetative features, they may have diverse sexual reproductive strategies. Here we compared the flowering morphology, floral biology, breeding system and pollinators of Tillandsia duratii, T. loliacea and T. recurvifolia (Bromeliaceae) adapted to an extreme environment, the Brazilian Chaco. Tillandsia duratii and T. recurvifolia flower for 5–6 months, whereas T. loliaceae flowers for 11 months, mainly in the dry season, with low to high flowering overlap between them. Although these species generally show similar flowering morphology, they differ in size, colour, odour and/or floral functionality, suggesting non-sharing of pollinators among them. Bimodal pollination occurs in T. duratii (bees, moths other than hawkmoths) and T. recurvifolia (butterflies, hummingbirds); in T. loliacea, we recorded no floral visitors. Tillandsia recurvifolia is self-incompatible, has flowers which approach herkogamy and protandry, and depends on pollen vectors for fruit set. The other two species show reverse herkogamy, autonomous self-pollination and self-compatibility (mixed breeding system); therefore, pollinators are not required. The disparity in reproductive strategies among the three species suggests the possibility of selection for diverse modes of reproduction.

scholarly journals Mass isolation and culture of rat kupffer cells.

1975 ◽  
Vol 141 (1) ◽  
pp. 1-10 ◽  
Author(s):  
A C Munthe-Kaas ◽  
T Berg ◽  
P O Seglen ◽  
R Seljelid
Keyword(s):  
Electron Microscopy ◽  
Tissue Culture ◽  
Liver Perfusion ◽  
K Cells ◽  
Highly Active ◽  
Transmission Electron ◽  
Acid Dnase ◽  
Collagenase Perfusion ◽  
Parenchymal Cells

Collagenase perfusion of the liver followed by pronase treatment of the cell suspension thus obtained gave a quantitative recovery of viable nonparenchymal liver cells (NPC). From these NPC, Kupffer (K) cells can be purified by attachment to tissue culture dishes. Tail vein injection of carbon 1-2 h before liver perfusion permitted stepwise calculation as well as visualization of carbon-containing K cells. When these K cells have been put into tissue culture medium with serum and incubated overnight, they exhibit typical macrophage characteristics. Phase-contrast and transmission electron microscopy showed typical macrophage morphology and scanning electron microscopy revealed well-spread cells with cytoplasmic projections and ruffled membranes. Endocytosis studies using radioactive colloidal gold and inert latex particles also indicated that these cells are highly active in pinocytosis and phagocytosis. Further characterization of K cells is the identification of Fc receptor on their membranes. Studies on lysosomal enzymes showed that purified K cells possess higher specific activities in beta-glucuronidase, acid DNase, and cathepsin D than in purified parenchymal cells.

Nectary ultrastructure and secretory modes in three species of Tillandsia (Bromeliaceae) that have different pollinators

Botany ◽  
2013 ◽  
Vol 91 (11) ◽  
pp. 786-798 ◽  
Author(s):  
Stefano Mosti ◽  
Cynthia Ross Friedman ◽  
Ettore Pacini ◽  
Luigi Brighigna ◽  
Alessio Papini
Keyword(s):  
Electron Microscopy ◽  
Amino Acids ◽  
Lipid Droplets ◽  
Protein Crystals ◽  
Transmission Electron ◽  
Floral Nectaries ◽  
Secretion Product ◽  
Pollination Mode ◽  
Cell Wall Ingrowths ◽  
Holocrine Secretion

The floral nectaries of three Tillandsia L. spp. having different pollinators were investigated with transmission electron microscopy (TEM) to describe the previously unstudied ultrastructure of the nectar-producing tissues (primarily the epidermis) and also to determine if any differences in the ultrastructural features could be correlated to pollination mode. We determined that there were variations in nectaries among the three species, and that these may be linked to pollinator choice. Tillandsia seleriana Mez, which has a strict relationship with ants, had a nectary epithelium characterized by abundant dictyosomes and endoplasmic reticulum (ER), and a final degeneration stage possibly leading to holocrine secretion. The presence of protein crystals in epithelial plastids was correlated to a nectar enriched with amino acids and proteins, likely functioning to provide a protein-enriched diet and possibly defence against pathogens. Epithelial cells of the hummingbird-pollinated Tillandsia juncea (Ruiz et Pav.) Poir. nectary displayed cell wall ingrowths and dictyosomes and also contained cytoplasmic lipid droplets and protein crystals within plastids, both of which would enrich the nectar for hummingbirds. The nectary epithelium and the parenchyma of bat-pollinated Tillandsia grandis Schltdl. possessed a few cubic protein crystals in the plastids and its secretion product appeared electron transparent.

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