scholarly journals Seed morphology and histology of some Paronychia taxa (Caryophyllaceae) from Turkey

1970 ◽  
Vol 38 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Ayse Kaplan ◽  
Hatice Çölgeçen ◽  
H Nurhan Büyükkartal
Keyword(s):  
Key Words ◽  
Seed Morphology ◽  
Epidermal Cells ◽  
Surface Structures ◽  
Dichotomous Key ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Seed morphology and histology of 12 taxa (nine species, two subspecies, one variety) of Paronychia Miller (Caryophyllaceae) by light and scanning electron microscopes revealed that seeds are laterally compressed, reniform, and hilums are linear. Testa surface structures are alveolate-scalariform, colliculate, reticulate-alveolate, rugose and ruminate. Differences in cuticle and papillae properties of epidermal cells have been observed. A dichotomous key has been developed for Paronychia agryloba Stapf, P. angorensis Chaudri, P. arabica (L.) DC. subsp. euphratica Chaudri, P. carica Chaudri, P. cataonica Chaudri, P. condensata Chaudri, P. davisii Chaudri, P. dudleyi Chaudri, P. galatica Chaudri, P. kurdica Boiss subsp. kurdica var. kurdica, P. kurdica Boiss subsp. montis-munzur Chaudri and P. mughlaei Chaudri.   Key words: Paronychia; Caryophyllaceae; Seed morphology; Seed histology; Turkey DOI: 10.3329/bjb.v38i2.5142 Bangladesh J. Bot. 38(2): 171-176, 2009 (December)  

scholarly journals Pollen morphology of some Turkish Campanula spp. and their taxonomic value

1970 ◽  
Vol 37 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Ismuhan Potoglu Erkara ◽  
Atila Ocak ◽  
Sevil Pehlivan
Keyword(s):  
Key Words ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Exine Sculpture ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
First Time ◽  
Scanning Electron

Detailed pollen morphological structures of 12 Turkish species of Campanula L., e.g. C. argaea, C. cymbalaria, C. glomerata subsp. hispida, C. latiloba subsp. latiloba, C. lyrata subsp. lyrata, C. olympica, C. persicifolia, C. pterocaula, C. rapunculoides subsp. cordifolia, C. rapunculus var. rapunculus, C. stricta var. stricta, C. pamphylica subsp. tokurii have been studied under light (LM) and scanning electron microscopes (SEM) for the first time. LM and SEM investigations show that the pollen grains of 12 taxa are more or less oblato-sphaeroidal, triporate (and/or tetraporate), tectum-scabrate, or with circular amb. The exine sculpture is granulate-scabrate in C. argaea, C. lyrata subsp. lyrata, C. stricta var. stricta, C. glomerata subsp. hispida and C. pamphylica subsp. tokurii; but those of C. cymbalaria, C. latiloba subsp. latiloba, C. olympica, C. persicifolia, C. pterocaula, C. rapunculoides subsp. cordifolia and C. rapunculus var. rapunculus are rugulate-scabrate.   Key words: Campanula, Pollen grains, Pollen morphology doi:10.3329/bjb.v37i1.1561 Bangladesh J. Bot. 37(1): 33-42, 2008 (June)

Andrographis megamalayana (Andrographinae: Acanthaceae), a new species from the southern Western Ghats, India

Phytotaxa ◽  
2016 ◽  
Vol 244 (1) ◽  
pp. 89
Author(s):  
Gunadayalan Gnanasekaran ◽  
Subbiah Karuppusamy ◽  
Garimella Venkata Suryanarayana Murthy
Keyword(s):  
New Species ◽  
Western Ghats ◽  
Conservation Status ◽  
Seed Morphology ◽  
Southern Western Ghats ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
A New Species ◽  
Scanning Electron

Andrographis megamalayana Gnanasek., Karupp. & G.V.S. Murthy (Andrographinae: Acanthaceae), a new species from the southern Western Ghats, India, is described here with illustrations, colour photographs, relationships with its allied species and IUCN conservation status. In addition, the pollen and seed morphology have been described here using Light and Scanning Electron Microscopes.

scholarly journals Morphological and anatomical features of seeds of Turkish Romulea taxa (Iridaceae) and their taxonomic significance

2015 ◽  
Vol 74 (1) ◽  
pp. 31-41 ◽  
Author(s):  
Mehmet Cengiz Karaismailoğlu
Keyword(s):  
Morphological Characteristics ◽  
Principal Component ◽  
Seed Morphology ◽  
Taxonomic Significance ◽  
Anatomical Features ◽  
Taxonomic Importance ◽  
Anatomical Characters ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Abstract This paper reports on the assessment of morphological (macro and micro) and anatomical characters of seeds of Romulea taxa distributed in Turkey with the use of oneway analysis of variance, cluster analysis and principal component analysis. Morphological characteristics such as size, shape, color and surface of seeds were examined with the use of light and scanning electron microscopes. Thicknesses of testa and phytomelan layer, sizes of embryo in seeds were studied anatomically. The outcomes revealed that taxa were similar in some aspects such as color and shape of seeds. However, seed size, thickness of testa and phytomelan layer, shape of the epidermal cells in testa and sizes of embryo were different among taxa, and have taxonomic value in the distinction of these taxa from each other. In addition, the seed surfaces were more or less different for the examined taxa on an interspecific level. Consequently, seed morphology and anatomy with a few exceptions demonstrated diversity and they had taxonomic importance in terms of distinguishing among species.

Development of cell arrangement in ostracod carapaces

Paleobiology ◽  
1981 ◽  
Vol 7 (2) ◽  
pp. 276-280 ◽  
Author(s):  
Yutaka Okada
Keyword(s):  
Epidermal Cell ◽  
Epidermal Cells ◽  
Ontogenetic Development ◽  
Gene Control ◽  
Ontogenetic Changes ◽  
Cell Arrangement ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

The correlation between epidermal cells and cuticular reticulation was clearly shown by transmission and scanning electron microscopes with larval ostracods just before ecdysis. Comparison of the reticulation patterns of Recent and Pleistocene specimens revealed that the epidermal cell arrangement of the adult ostracods is both consistent in the Recent population and conservative in phylogeny. Ontogenetic changes of the reticulation pattern were studied with specimens cultivated separately. Some gene control over the mitosis of epidermal cells was assumed, based on the ontogenetic development of the reticulation pattern. The pattern of fossil specimens suggests that the control has been well maintained in ostracod phylogeny.

scholarly journals Pollen morphology of some Turkish Ajuga L. (Lamiaceae) and its taxonomic value

1970 ◽  
Vol 40 (1) ◽  
pp. 29-33 ◽  
Author(s):  
Yavuz Bulent Kose ◽  
Ismahan Potoglu Erkara ◽  
Sevim Alan
Keyword(s):  
Key Words ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Exine Sculpture ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
First Time ◽  
Scanning Electron

Pollen morphological structures of eight Turkish species of Ajuga, namely A. bombycina Boiss., A. chamaepitys (L.) Schreber ssp. chia var. chia (Schreber) Arcangeli, A. chamaepitys (L.) Schreber ssp. chia var. ciliata Briq., A. chamaepitys (L.) Schreber ssp. cuneatifolia (Stapf) P. H. Davis, A. genevensis L., A. laxmannii (L.) Benthum, A.orientalis L. and A. reptans L. have been studied under light and scanning electron microscopes for the first time. It is revealed that the pollen grains of Ajuga taxa are more or less suboblata-subprolata and tricolpatae. The exine sculpture is granulate in A. chamaepitys subsp. chia var. chia, A. chamaepitys subsp. cuneatifolia, A. genevensis, A. laxmannii, A. orientalis and A. reptans, but it is reticulate in A. bombycina and A. chamaepitys subsp. chia var. ciliata. Key words: Turkish Ajuga; Pollen morphology; Taxonomic value DOI: http://dx.doi.org/10.3329/bjb.v40i1.7994 Bangladesh J. Bot. 40(1): 29-33, 2011 (June)

Current State of Biological High-Resolution Scanning Electron Microscopy

1988 ◽  
Vol 46 ◽  
pp. 180-181 ◽  
Author(s):  
Klaus-Ruediger Peters
Keyword(s):  
High Performance ◽  
Low Voltage ◽  
Backscattered Electrons ◽  
Lens Position ◽  
Low Voltage Operation ◽  
Signal Collection ◽  
Probe Size ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

A new generation of high performance field emission scanning electron microscopes (FSEM) is now commercially available (JEOL 890, Hitachi S 900, ISI OS 130-F) characterized by an "in lens" position of the specimen where probe diameters are reduced and signal collection improved. Additionally, low voltage operation is extended to 1 kV. Compared to the first generation of FSEM (JE0L JSM 30, Hitachi S 800), which utilized a specimen position below the final lens, specimen size had to be reduced but useful magnification could be impressively increased in both low (1-4 kV) and high (5-40 kV) voltage operation, i.e. from 50,000 to 200,000 and 250,000 to 1,000,000 x respectively.At high accelerating voltage and magnification, contrasts on biological specimens are well characterized1 and are produced by the entering probe electrons in the outmost surface layer within -vl nm depth. Backscattered electrons produce only a background signal. Under these conditions (FIG. 1) image quality is similar to conventional TEM (FIG. 2) and only limited at magnifications >1,000,000 x by probe size (0.5 nm) or non-localization effects (%0.5 nm).

Observation of GaAs/AlAs Superlattice Structures in both Secondary and Backscattcred Electron Imaging Modes with an Ultrahigh Resolution Scanning Electron Microscope

1990 ◽  
Vol 48 (1) ◽  
pp. 404-405
Author(s):  
K. Ogura ◽  
A. Ono ◽  
S. Franchi ◽  
P.G. Merli ◽  
A. Migliori
Keyword(s):  
Gaas Layer ◽  
Objective Lens ◽  
Superlattice Structure ◽  
Backscattered Electron ◽  
Instrumental Resolution ◽  
Electron Microscopes ◽  
Superlattice Structures ◽  
Electron Imaging ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

In the last few years the development of Scanning Electron Microscopes (SEM), equipped with a Field Emission Gun (FEG) and using in-lens specimen position, has allowed a significant improvement of the instrumental resolution . This is a result of the fine and bright probe provided by the FEG and by the reduced aberration coefficients of the strongly excited objective lens. The smaller specimen size required by in-lens instruments (about 1 cm, in comparison to 15 or 20 cm of a conventional SEM) doesn’t represent a serious limitation in the evaluation of semiconductor process techniques, where the demand of high resolution is continuosly increasing. In this field one of the more interesting applications, already described (1), is the observation of superlattice structures.In this note we report a comparison between secondary electron (SE) and backscattered electron (BSE) images of a GaAs / AlAs superlattice structure, whose cross section is reported in fig. 1. The structure consist of a 3 nm GaAs layer and 10 pairs of 7 nm GaAs / 15 nm AlAs layers grown on GaAs substrate. Fig. 2, 3 and 4 are SE images of this structure made with a JEOL JSM 890 SEM operating at an accelerating voltage of 3, 15 and 25 kV respectively. Fig. 5 is a 25 kV BSE image of the same specimen. It can be noticed that the 3nm layer is always visible and that the 3 kV SE image, in spite of the poorer resolution, shows the same contrast of the BSE image. In the SE mode, an increase of the accelerating voltage produces a contrast inversion. On the contrary, when observed with BSE, the layers of GaAs are always brighter than the AlAs ones , independently of the beam energy.

Discoasters of the Blue Clay (Middle Miocene) of Malta and Gozo

1978 ◽  
Vol 115 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Minoo Hojjatzadeh
Keyword(s):  
Middle Miocene ◽  
The Family ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

SummaryTwenty-three species of the Family Discoasteraceae Vekshina, 1959 recovered from 18 samples of the Blue Clay at Fort Chambray, Gozo, and 31 samples from Fomm-Ir-Rih Bay, Malta, have been studied under light and scanning electron microscopes. Fourteen Middle Miocene species are reviewed, their stratigraphical ranges and importance as marker species discussed. Nine species are described as new. On the basis of the discoaster species present, a Middle Miocene age (NN.6 Discoaster exilis Zone – NN.7 Discoaster kugleri Zone) for the Blue Clay in Malta and Gozo is suggested.

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