scholarly journals Micromorphology of nectaries of Rhododendron catawbiense Michx. at different flower development stages

2012 ◽  
Vol 60 (2) ◽  
pp. 15-22 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Mirosława Chwil ◽  
Magdalena Michońska

The analysis of the structure of fl oral nectaries of <i>Rhododendron catawbiense</i> Michx. was performed using stereoscopic, light and scanning electron microscopy. Nectaries were sampled at different development stages: closed bud, budburst and full bloom. The nectary gland exhibits clear ribbings corresponding to fi ve small ribs of the ovary. In the top part of the gland, unicellular and multicellular non-glandular trichomes occur in great density. The upper surface of the nectary differs from its lateral surface by a stronger degree of cuticle development. Stomata are evenly distributed on the upper surface and in the higher regions of the lateral wall. The cuticle forms clear striae on the surface of stomatal cells. Stomata at different development stages were observed, as well as the beginning of nectar secretion which takes places already in the closed bud.

2017 ◽  
Vol 23 (3) ◽  
pp. 679-686 ◽  
Author(s):  
Milan Gavrilović ◽  
Suzana Erić ◽  
Petar D. Marin ◽  
Núria Garcia-Jacas ◽  
Alfonso Susanna ◽  
...  

AbstractIn this work, weddellite and sylvite crystals are identified for the first time on the involucral bracts and petals of Xeranthemum annuum and Xeranthemum cylindraceum using scanning electron microscopy coupled with energy dispersive spectrometric (SEM-EDS) analysis. Well-developed crystals of weddellite (CaC2O4·2H2O) occur in the form of a tetragonal bipyramid (hhl), rarely in combination of a bipyramid and tetragonal prism (h00). Indumentum of involucral bracts of X. cylindraceum consists of nonglandular and glandular trichomes. Sylvite (KCl) crystals are observed only on the petal surface of X. cylindraceum. The crystals of sylvite occur in the form of perfect cubes (hexahedrons), but some crystals are deformed, i.e., partially elongated. Taxonomic significance of investigated microcharacters as well as the use of SEM-EDS analysis in taxonomic studies of plants are discussed.


2012 ◽  
Vol 40 (1) ◽  
pp. 35 ◽  
Author(s):  
Hüseyin CILDIR ◽  
Ahmet KAHRAMAN ◽  
Musa DOGAN

In this study, the epidermal types and their distribution on dorsal and lateral petals, the trichome types and their density on sepals of Lathyrus chloranthus, L. digitatus, L. laxiflorus subsp. laxiflorus, L. roseus subsp. roseus, L. sativus, and L. tuberosus, belonging to sections Lathyrus, Lathyrostylis, Pratensis, and Orobon of the genus Lathyrus in Turkey were investigated using light microscopy (LM) and scanning electron microscopy (SEM), and the systematic significance of these characters was evaluated. These taxa, except L. sativus, are studied for the first time under aspects of the petal and sepal micromorphology. Three major epidermal types were recognized on the petal: tabular rugose striate cells (TRS), areolate cells with more or less striations (AS), and papillose conical striate cells (PCS). TRS and AS were further subdivided into three subtypes. TRS was found on the dorsal and lateral petals of L. chloranthus, L. sativus, and L. tuberosus: the dorsal petals of L. roseus subsp. roseus and the lateral petals of L. laxiflorus subsp. laxiflorus, while AS was present on the dorsal and lateral petals of L. digitatus and the lateral petals of L. roseus subsp. roseus. PCS was found only on the dorsal petals of L. digitatus. Three main types of trichomes on the sepal were observed: peltate glandular, capitate glandular, and nonglandular trichomes. The capitate glandular and nonglandular trichomes were further subdivided into three subtypes. The peltate glandular trichomes were present only in L. chloranthus, but absent in the others. The capitate glandular trichomes were found in L. chloranthus, L. laxiflorus subsp. laxiflorus, L. roseus subsp. roseus, and L. tuberosus. The nonglandular trichomes were always present in L. chloranthus and L. laxiflorus subsp. laxiflorus. The present results show that the petal and sepal micromorphology can be used in delimitation of the taxa based on petal and sepal micromorphology.


1993 ◽  
Vol 48 (9-10) ◽  
pp. 736-744 ◽  
Author(s):  
Ralf Engel ◽  
Paul-Gerhard Gülz ◽  
Thorsten Herrmann ◽  
Adolf Nahrstedt

Glandular trichomes in form of long stretched tubes are present on the lower leaf side of Quercus robur as shown by scanning electron microscopy. The glands contain an essential oil, which was isolated by steam distillation together with volatile waxy components of the leaves in an amount of 0.025% of fresh leaves. The product of steam distillation was analyzed by GC-MS. Identification of com pounds is based on comparison of their mass spectral data with those of authentic samples in combination with retention indices and MS data using the SeKoMS (Search Kovats Indices and Mass Spectra) Library. Altogether 184 components of the product of steam distillation were separated, 155 of which could be identified, another 7 were tentatively assigned. Three groups of substances according to their chemical composition are found: hexenyl derivatives and some acetals (32%); terpenes including monoterpenes (4% ), sesquiterpenes and diterpenes (21%); and alkane derivatives (35%). The residual 8% consist of benzyl alcohol, com pounds which stem from the degradation of carotenes, and miscellaneous constituents


1980 ◽  
Vol 58 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Earic E. Karrfalt ◽  
Gerald L. Kreitner

The development of the stalked, capitate, glandular trichomes found on the inflorescence axes of Adenocaulon bicolor was studied by light and scanning electron microscopy. The trichomes are not initiated until the stems have essentially ceased to grow in diameter. In early development the trichomes are biseriate, but later become several cells wide partly as the result of contributions from other epidermal cells rather than exclusively from longitudinal divisions in the developing trichome. Cell divisions occur throughout the trichome primordia and are not restricted to an acropetal or basipetal sequence. The mature trichomes are relatively large, 200–250 μm high, but are entirely of epidermal origin.


2012 ◽  
Vol 64 (3) ◽  
pp. 995-1000 ◽  
Author(s):  
Marija Marin ◽  
Lia Ascensao ◽  
Branislava Lakusic

Considering the importance of Satureja horvatii Silic as an endemic plant, and due to the essential oils produced in its glandular trichomes, we have done a comprehensive study of the micromorphology and a histochemical analysis of the plant?s glandular trichomes. This investigation was carried out using light microscopy and scanning electron microscopy. Non-glandular unbranched and three types of glandular trichomes on the leaf surface - peltate, capitate and digitiform - were investigated. The results of histochemical tests showed a positive reaction to polysaccharides, proteins, pectins, lipids and to some secondary compounds such as terpenes, tannins and phenols in different types of glandular trichomes.


Phytotaxa ◽  
2021 ◽  
Vol 527 (1) ◽  
pp. 51-59
Author(s):  
RAFAEL COSTA-SILVA ◽  
LEANDRO LACERDA GIACOMIN ◽  
MARIA DE FATIMA AGRA

During our analyses of Lycianthes exsiccates, as part of the taxonomic treatment for the Brazilian flora, a new species was discovered and is described and illustrated here. The species is compared and contextualized within the infra-generic classification of Lycianthes. Analyses of indument and trichomes were performed by stereomicroscopy (SM) and scanning electron microscopy (SEM). The new species, Lycianthes amazonica, is recognized as an endemic species to the Brazilian Amazon, which has its habitat described as secondary formations (capoeira) of terra-firme forests. It is closely related to L. sprucei, with which shares the scandent or vine habit, flexuous branches and ferrugineous indument of glandular trichomes. However, they are distinguished by several morphological features, including trichomes morphology, a sessile inflorescence and calyx appendages of equal length; both species belong to Lycianthes. subg. Polymeris sect. Eulycianthes ser. Glanduliferae. The description of this species expands the total number of Lycianthes species to the Brazilian Amazon to six, as well as thirteen to Brazil. The affinities of Lycianthes amazonica with its related species, distribution, ecology, and conservation status are discussed. Additionally, a lectotypification of Lycianthes sprucei, a species closely related to L. amazonica, is proposed.


Zygote ◽  
2008 ◽  
Vol 16 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Camila Marques ◽  
Laura Satiko Okada Nakaghi ◽  
Francine Faustino ◽  
Luciana Nakaghi Ganeco ◽  
José Augusto Senhorini

SummaryPseudoplatystoma coruscans is a very popular species for tropical fish culture as it has boneless meat of delicate taste and firm texture. Few studies on fish reproductive biology refer to the morphological features of eggs. The goal, therefore, of this present work was to perform a structural and ultrastructural analysis of fertilization and embryonic development in P. coruscans. The incubation period, from fertilization to hatching, lasts 13 h at 28/29 °C and 18 h at 27 °C. The oocytes had a mean diameter of 0.95 mm and hatched larvae were 2.55 mm in diameter. Analysing their development, we observed round, yellow oocytes that bore a double chorion membrane and a single micropyle. At 10 s after fertilization, several spermatozoa were detected attached to the oocyte surface. After 1 min of development, a fertilization cone that obstructed the micropyle could be observed. Segmentation started between 20 and 30 min after fertilization, when the egg cell was then formed. The first cleavage occurred between 30 and 45 min after fertilization, prior to reaching the morula stage (75 and 90 min after fertilization). The epiboly movement started at 120 and 180 min after fertilization and ended at 360 and 480 min after fertilization. Differentiation between cephalic and caudal region was detected after 420 and 600 min after fertilization and larvae hatched between 780 and 1080 min after fertilization. Seven main embryonic development stages were identified: egg cell, cleavage, morula, blastula, gastrula, segmentation with differentiation between cephalic and caudal regions, and hatching.


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