scholarly journals Biometrics of the sporangia and spores of the Parablechnum cordatum complex (Blechnaceae, Polypodiopsida)

2021 ◽  
Vol 45 ◽  
pp. e73655
Author(s):  
Aleksandra Patrjcia Wal ◽  
Sonia Molino ◽  
Antonio Murciano ◽  
Carmen Prada ◽  
José María Gabriel y Galán
Keyword(s):  
Electron Microscope ◽  
Discriminant Analysis ◽  
Scanning Electron Microscope ◽  
Analysis Of Variance ◽  
Pacific Region ◽  
Taxonomic Significance ◽  
Biometric Analysis ◽  
Equatorial Diameter ◽  
Number Of Cells ◽  
Scanning Electron

Parablechnum is the most diverse genus of Blechnaceae (ca. 65 species), with a pantropical distribution and two centers of diversity, in America and in the Austro-Pacific region. The species are dimorphic, with often erect rhizomes and rhizomatic scales, 1-pinnate fronds, with truncate blade at base, conform apex and stalked pinnae. This group presents many taxonomic problems, needing more detailed studies to resolve these conflicts of separation between species. This work deals with the American complex of P. cordatum in which the species P. cordatum, P. schiedeanum, P. chilense, P. falciforme and Blechnum varians are included. A biometric analysis of sporangia and spores, important taxonomic structures in the distinction of ferns, has been carried out. The data were subjected to a one-way analysis of variance and a discriminant analysis. In addition, the spores were observed under a scanning electron microscope to study their ornamentation. Of the characters we have studied thickness of the arcus, number of cells in the arcus, number of cells in the hypostome and major equatorial diameter of the spore have statisticalParablechnum is the most diverse genus of Blechnaceae (ca. 65 species), with a pantropical distribution and two centers of diversity, in America and in the Austro-Pacific region. The species are dimorphic, with often erect rhizomes and rhizomatic scales, 1-pinnate fronds, with truncate blade at base, conform apex and stalked pinnae. This group presents many taxonomic problems, needing more detailed studies to resolve these conflicts of separation between species. This work deals with the American complex of P. cordatum in which the species P. cordatum, P. schiedeanum, P. chilense, P. falciforme and Blechnum varians are included. A biometric analysis of sporangia and spores, important taxonomic structures in the distinction of ferns, has been carried out. The data were subjected to a one-way analysis of variance and a discriminant analysis. In addition, the spores were observed under a scanning electron microscope to study their ornamentation. Of the characters we have studied thickness of the arcus, number of cells in the arcus, number of cells in the hypostome and major equatorial diameter of the spore have statistically supported taxonomic significance and are therefore useful for species separation.  

An Inverse Relation Between Cell Density and the Number of Microvilli in Cultures of BHK 21 Hamster Fibroblasts

1970 ◽  
Vol 7 (3) ◽  
pp. 695-709
Author(s):  
C. H. O'NEILL ◽  
E. A. C. FOLLETT
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Monolayer Culture ◽  
Cell Contact ◽  
Inverse Relation ◽  
Culture Density ◽  
Microscope Technique ◽  
The Relationship ◽  
Number Of Cells ◽  
Scanning Electron

The relationship between culture density and the number of microvilli on the cell surface has been studied using BHK21 cells in established monolayer culture. The number of microvilli can be estimated quantitatively by a scanning electron-microscope technique. It can be increased by applying specific antiserum, but whether antibody is applied or not a significant number of cells regularly bear microvilli. This number is characteristic of the culture density. In sparse cultures above a certain minimum density it is relatively high, and in confluent cultures it is much reduced. These results indicate that microvilli may be inhibited by cell contact.

Cypsela morphology of Cirsium sect. Cirsium (Asteraceae) taxa in Turkey

Biologia ◽  
2011 ◽  
Vol 66 (6) ◽  
Author(s):  
Serkan Köstekci ◽  
Turan Arabaci
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Surface Characteristics ◽  
Taxonomic Significance ◽  
Sem Investigation ◽  
Scanning Electron

AbstractIn this study, the cypsela morphology of 21 (14 species) of the 28 (17 species) Turkish Cirsium Mill. sect. Cirsium (Asteraceae) taxa was examined by stereomicroscope and scanning electron microscope (SEM). The shapes of cypselas are oblong, obovate, narrowly obovate and oblanceolate. The taxa were divided into 7 main types according to the results of SEM investigation on cypsela surface characteristics as: scalariform, ribbed, scrobiculate-ribbed, scrobiculate, scrobiculate-reticulate, reticulate and bireticulate. Taxonomic significance of cypsela morphology is discussed. It is shown that cypsela features can be used as distinguishing characteristics in some Cirsium sect. Cirsium species.

scholarly journals Taxonomic significance of spermoderm pattern in Cucurbitaceae

2013 ◽  
Vol 20 (1) ◽  
pp. 61-65
Author(s):  
M. Ajmal Ali ◽  
Fahad M.A. Al-Hemaid ◽  
Arun K. Pandey ◽  
Joongku Lee
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Cucumis Melo ◽  
Taxonomic Significance ◽  
Citrullus Colocynthis ◽  
Benincasa Hispida ◽  
The Family ◽  
Plant Taxon ◽  
Relationship Of ◽  
Scanning Electron

Studies on spermoderm using scanning electron microscope (SEM) were undertaken in 12 taxa under 11 genera of the family Cucurbitaceae sampled from India, China and Korea. The spermoderm pattern in the studied taxa varies from rugulate, reticulate to colliculate type. The spermoderm shows rugulate type in Benincasa hispida and Sicyos angulatus; reticulate type in Citrullus colocynthis, Cucumis melo var. agrestis, Diplocyclos palmatus, Hemsleya longivillosa, Luffa echinata, Momordica charantia, M. cymbalaria, Schizopepon bryoniifolius, and Trichosanthes cucumerina; and colliculate type  in Gynostemma laxiflorum. The present study clearly reveals that the testa features greatly varies across the genera which can be used as micromorphological markers for identification as well as character states for deducing relationship of the taxa within the family.DOI: http://dx.doi.org/10.3329/bjpt.v20i1.15465Bangladesh J. Plant Taxon. 20(1): 61-65, 2013 (June)

scholarly journals Pollen morphology of chestnut cultivars in southern China by using scanning electron microscope

2020 ◽  
Vol 49 (1) ◽  
pp. 39-46
Author(s):  
Huan Xiong ◽  
De-Yi Yuan ◽  
Ya Chen ◽  
Genhua Niu ◽  
Feng Zou
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Southern China ◽  
Morphological Characteristics ◽  
Pollen Grains ◽  
Polar Axis ◽  
Upgma Tree ◽  
Equatorial Diameter ◽  
Components Analysis ◽  
Scanning Electron

The morphological characteristics of pollen grains of 16 cultivars belonging to two species of the genus Castanea (Castanea mollissima and C. henryi) collected from southern China were observed by using scanning electron microscope (SEM). The length of polar axis (PL), the equatorial diameter (ED), the length of colpus (CL) of grain, P/E ratio (polar axis to equatorial diameter), P/C ratio (polar axis to colpus length), and C/E ratio (colpus length to equatorial diameter) were measured and their variations were compared among studied taxa. The result of this study indicated that chestnut pollen grain was a tricolporate in aperture type, and aperprolate type in equatorial view. The morphological characteristics were mainly represented by PL, ED and CL as revealed by principal components analysis, which accounted for 99.56% of the total variations. The cluster analysis by the UPGMA tree divided the taxa into three groups and showed a great morphological affinity among the 16 cultivars.

scholarly journals A high-yield technique for preparing cells fixed in suspension for scanning electron microscopy.

1975 ◽  
Vol 67 (2) ◽  
pp. 476-480 ◽  
Author(s):  
S K Sanders ◽  
E L Alexander ◽  
R C Braylan
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Quantitative Comparison ◽  
High Yield ◽  
Live Cells ◽  
A Cell ◽  
Number Of Cells ◽  
Scanning Electron

Human leukocytes fixed in suspension were allowed to settle onto poly-L-lysine-coated glass coverslips and prepared for observation with the scanning electron microscope (SEM). The coverslips were dehydrated in ethanol, critical point dried with CO2, and coated with gold-palladium. With the aid of a locator grid, several fields were photographed with light microscopy after the cells had settled onto the poly-L-lysine-coated coverslips and again after completion of the processing before SEM observation. Quantitative comparison of the number of cells present after settling with the number retained for final viewing with the SEM revealed a cell yield approaching 100%. This simple, reproducible, high-yield technique for processing cells fixed in suspension for SEM prevents changes in surface architecture induced by collecting live cells onto various substrates before fixation and also avoids potentially selective cell losses. Such a technique should allow quantitative correlations between SEM and other morphological and functional parameters.

scholarly journals A comparative study of achene morphology in Korean Polygonaceae

2018 ◽  
Vol 25 (2) ◽  
pp. 135-148
Author(s):  
Min-Jung Kong ◽  
Jun-Ho Song ◽  
Beom-Cheol An ◽  
Sung-Won Son ◽  
Gang-Uk Suh ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Morphological Characteristics ◽  
Species Level ◽  
Taxonomic Significance ◽  
Stereo Microscope ◽  
Surface Patterns ◽  
Fagopyrum Esculentum Moench ◽  
Rumex Maritimus ◽  
Scanning Electron

A comparative macro- and micromorphological study was conducted on achenes of Korean Polygonaceae comprising 45 taxa under 10 genera using a Stereo-microscope (SM) and Scanning Electron Microscope (SEM) to evaluate the taxonomical relevance of achene morphological characteristics. The achene shape is lenticular, biconvex, trigonous, or spheroidal. The largest achenes are found in Fagopyrum esculentum Moench (5.80–6.70 × 3.90–4.40 mm) and Rheum rhabarbarum L. (5.00–6.50 × 4.00–5.20 mm), and the smallest is found in Rumex maritimus L. (1.17–1.41 × 0.60–0.84 mm). Three types of embryo shape (curved, straight, and folded) and two types of embryo position (plane and parietal) can be distinguished. Most taxa have a curved embryo shape with plane position. Four types of surface patterns (smooth, papillae, tuberculate, or small pits) are observed. The surface sculpture or embryo type is rather consistent at the generic or tribal level, and the comprehensive consideration of achene characteristics is also useful at the species level. The achene morphology is described in detail, compared, and illustrated. The taxonomic significance of the achene morphology is discussed.

scholarly journals Pollen morphology of 10 taxa belonging to Prangos Lindl. and Ekimia H. Duman & M.F. Watson (Umbelliferae) from turkey and its taxonomic significance

2009 ◽  
Vol 16 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Sevil Pehlivan ◽  
Birol Baser ◽  
Evren Cabi
Keyword(s):  
Cluster Analysis ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
No Value ◽  
Quantitative Data ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Taxonomic Significance ◽  
Transmission Electron ◽  
Scanning Electron

Pollen grains of nine taxa of Prangos Lindl. and one of Ekimia H. Duman & M.F. Watson (Umbelliferae) were examined with LM (light microscope) and SEM (scanning electron microscope), and of them four with TEM (transmission electron microscope). The quantitative data were also subjected to cluster analysis. The obtained phenogram revealed that Ekimia bornmuelleri (Hub.-Mor. & Reese) H. Duman & M.F. Watson is strictly different from the taxa of Prangos regarding their quantitative pollen profile; except P. ferulacea Lindl., all taxa included in section Intactae formed a cluster together; members of section Meliocarpoides and section Prangos show a closer relationship regarding their pollen features. Exine ornamentations of Prangos and Ekimia are rugulate-striate and are of no value for identification purposes.

scholarly journals Archaeopyle variability in Early Cretaceous dinocysts of the partiform gonyaulacoid genus <i>Druggidium</i> Habib

1986 ◽  
Vol 5 (2) ◽  
pp. 17-26 ◽  
Author(s):  
Ian C. Harding
Keyword(s):  
Electron Microscope ◽  
New Species ◽  
Scanning Electron Microscope ◽  
Early Cretaceous ◽  
Taxonomic Significance ◽  
One New Species ◽  
Scanning Electron

Abstract. Scanning electron microscope (S.E.M.) observation techniques have enabled paratabulation formulae to be elucidated (in both Kofoidian and Taylor-Evitt notation) for the partiform gonyaulacoid dinocyst genus Druggidium Habib. Archaeopyle variability within the species of this genus is highlighted, further emphasising the uncertainties concerning the taxonomic significance of archaeopyle type. The genus Druggidium is therefore emended, as is the species D. jubatum Duxbury. One new species, D. augustum, is described.

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