Punctastriata altera sp. nov. (Bacillariophyta, Fragilariophyceae), a diatom from the United States of America

Phytotaxa ◽  
2021 ◽  
Vol 516 (3) ◽  
Author(s):  
EDUARDO A. MORALES
Keyword(s):  
Electron Microscopy ◽  
United States ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
United States Of America ◽  
The United States ◽  
Scanning Electron

The genus Punctastriata D.M.Williams & Round (1988: 278) contains 10 species that are difficult to identify under light microscopy (LM) (Wetzel & Ector 2021, Morales et al. 2021). The difficulty lies in the differentiation of the overall valve outline and striation pattern of these species from members of Staurosirella D.M.Williams & Round (1988: 274). Under scanning electron microscopy (SEM), the striae of species of Punctastriata are typically multiseriate, the consequence of a profuse formation of viminules. In Staurosirella, the striae are composed of long and slender vimines delimiting apically oriented lineolae (Morales et al. 2021), while the production of viminules is incomplete and rare (Morales 2005).

Ultrastructure Of Conidium And Disjunctor Development In The Plant Pathogenic Fungus Monilinia Vaccinii-Corymbosi

1999 ◽  
Vol 5 (S2) ◽  
pp. 1278-1279
Author(s):  
C. W. Mims ◽  
E. A. Richardson
Keyword(s):  
Electron Microscopy ◽  
United States ◽  
Scanning Electron Microscopy ◽  
Pathogenic Fungus ◽  
The United States ◽  
Exact Nature ◽  
Taxonomic Character ◽  
Plant Pathogenic Fungus ◽  
Disease Initiation ◽  
Scanning Electron

Monilinia vaccinii-corymbosi is the cause of mummy berry disease of commercial blueberries (Vaccinium spp.) grown in the United States and Canada (1). Ovaries of blueberry flowers are infected by the conidia (asexual spores) of this pathogen. However, despite their importance in disease initiation, little is known of the ultrastructural features of these conidia. The only ultrastructural data on these spores has come from the work of Batra (2) who used scanning electron microscopy to describe the morphology of the so-called “disjunctors” which connect adjacent conidia of M. vaccinii-corymbosi. The presence or absence of disjunctors is an important taxonomic character in the genus Monilinia (1) but little is known of their development and exact nature. The objective of this study was, therefore, to elucidate details of conidium and disjunctor development in M. vaccinii-corymbosi.

Wall Sculpturing in Vessel Elements of Juglans Species of the United States

IAWA Journal ◽  
2008 ◽  
Vol 29 (2) ◽  
pp. 153-160
Author(s):  
Young Geun Eom ◽  
Ohkyung Kwon ◽  
Robert B. Hanna ◽  
Robert W. Meyer
Keyword(s):  
Electron Microscopy ◽  
United States ◽  
Scanning Electron Microscopy ◽  
Vessel Wall ◽  
The United States ◽  
Diagnostic Value ◽  
Black Walnut ◽  
Large Vessel ◽  
Vessel Elements ◽  
Scanning Electron

Wall sculpturing in the vessel elements of some Juglans species of the United States, four black walnuts (J. major, J. nigra, J. microcarpa (= J. rupestris), and J. californica) and one butternut (J. cinerea), was investigated through light and scanning electron microscopy. This feature showed various forms such as helical and reticulate thickenings, and thickening-like structures formed by coalescent pit apertures and large vessel to ray pits. Light to prominent wall sculpturing occurred regularly in black walnuts but fine and indistinctive wall sculpturing was observed rarely in butternut. Thus, vessel wall sculpturing was of some diagnostic value for separating black walnut from butternut.

Isoetes ×echtuckerii, hyb. nov., a new triploid quillwort from northeastern North America

2000 ◽  
Vol 77 (11) ◽  
pp. 1662-1668 ◽  
Author(s):  
Daniel F Brunton ◽  
Donald M Britton
Keyword(s):  
Electron Microscopy ◽  
United States ◽  
Scanning Electron Microscopy ◽  
North America ◽  
United States Of America ◽  
Interspecific Hybrid ◽  
Eastern Canada ◽  
Northeastern North America ◽  
Spore Ornamentation ◽  
Scanning Electron

A new interspecific Isoetes hybrid, I. echinospora Dur. × I. tuckermanii A. Br., is described from northeastern North America by means of cytology and the scanning electron microscopy of spores. Isoetes ×echtuckerii D.F. Brunton and D.M. Britton, hyb. nov., is the name proposed for this taxon. It is triploid, produces only aborted, sterile spores and has spore ornamentation intermediate between that of its putative parents. Populations have been identified in eastern Canada and the adjacent United States of America growing in association with one or both parents in shallow, fresh water along oligotrophic lake and river shores. Key words: Isoetes ×echtuckerii, interspecific hybrid, Canada, United States of America.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Examination of Schistosome Cercariae and Schistosomules by Scanning Electron Microscopy

1969 ◽  
Vol 27 ◽  
pp. 50-51
Author(s):  
D. Johnson ◽  
P. Moriearty
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Light Microscopy ◽  
Surface Structure ◽  
Extensive Study ◽  
Scanning Microscopy ◽  
Host Parasite ◽  
Conventional Electron Microscopy ◽  
Scanning Electron

Since several species of Schistosoma, or blood fluke, parasitize man, these trematodes have been subjected to extensive study. Light microscopy and conventional electron microscopy have yielded much information about the morphology of the various stages; however, scanning electron microscopy has been little utilized for this purpose. As the figures demonstrate, scanning microscopy is particularly helpful in studying at high resolution characteristics of surface structure, which are important in determining host-parasite relationships.

SEM Observations on the Germination of Euonymous Americanus

1985 ◽  
Vol 43 ◽  
pp. 508-509
Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Filter Paper ◽  
Room Temperature ◽  
Food Source ◽  
Environmental Chamber ◽  
Dormant Stage ◽  
Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

Scanning electron microscopy of asbestos-containing material where the asbestos fibers are considered locked in a binder

1993 ◽  
Vol 51 ◽  
pp. 472-473
Author(s):  
J. R. Millette ◽  
R. S. Brown
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Protection Agency ◽  
Building Materials ◽  
The United States ◽  
Protection Agency ◽  
Asbestos Fibers ◽  
Different Types ◽  
Binder Material ◽  
Scanning Electron

The United States Environmental Protection Agency (EPA) has labeled as “friable” those building materials that are likely to readily release fibers. Friable materials when dry, can easily be crumbled, pulverized, or reduced to powder using hand pressure. Other asbestos containing building materials (ACBM) where the asbestos fibers are in a matrix of cement or bituminous or resinous binders are considered non-friable. However, when subjected to sanding, grinding, cutting or other forms of abrasion, these non-friable materials are to be treated as friable asbestos material. There has been a hypothesis that all raw asbestos fibers are encapsulated in solvents and binders and are not released as individual fibers if the material is cut or abraded. Examination of a number of different types of non-friable materials under the SEM show that after cutting or abrasion, tuffs or bundles of fibers are evident on the surfaces of the materials. When these tuffs or bundles are examined, they are shown to contain asbestos fibers which are free from binder material. These free fibers may be released into the air upon further cutting or abrasion.

New diagnostic characters of Kolhymorbis angarensis (Dybowski & Grochmalicki, 1925) (Gastropoda: Pulmonata: Planorbidae)

2009 ◽  
Vol 18 (2) ◽  
pp. 191-195
Author(s):  
E.V. Soldatenko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Diagnostic Characters ◽  
Copulatory Apparatus ◽  
Scanning Electron

The radula morphology and the anatomy of the copulatory apparatus in Kolhymorbis angarensis were examined using light microscopy, scanning electron microscopy (SEM) and histological methods. Kolhymorbis angarensis was shown to have the stylet and the penial sac with a glandular appendage (flagellum), the characteristics, previously unknown for any species of this genus. The significance of these findings for the taxonomy of the genus is discussed.

A Comparative Study of Trichomes in Angophora Cav. And Eucalyptus L'hérit. - A Question of Homology

1984 ◽  
Vol 32 (5) ◽  
pp. 561 ◽  
Author(s):  
PY Ladiges
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Comparative Study ◽  
Light Microscopy ◽  
Evolutionary Trends ◽  
Oil Glands ◽  
Ancestral Condition ◽  
Scanning Electron

The trichomes of Angophora and Eucalyptus are illustrated from scanning electron microscopy and light microscopy, and evolutionary trends are discussed. Bristle glands of Angophora and Eucalyptus subgen. Blakella and Corymbia are emergent oil glands of varying lengths. Emergent oil glands occur in all other Eucalyptus subgenera but they are most conspicuous in Blakella, Corymbia and Angophora, in which they are characterized by four cap cells each ornamented with micropapillae. Hairs in Angophora are unique, being multicellular; they are also uniseriate and scattered on the epidermis. In contrast, hairs in Eucalyptus are simple extensions, short or long, of the cells on the sides of or the cap cells of the emergent oil glands, and they are not homologous with those of Angophora. Eucalyptus setosa (subgen. Blakella) and E. brockwayi (subgen. Symphyomyrtus) are two exceptions, having unicellular hairs on the epidermis, not associated with oil glands. It is suggested that this is an ancestral condition (or secondary reversal to it).

Taxonomic application of macro and micro morphological characters of seeds in Astragalus L. (Galegeae, Fabaceae) in India

Phytotaxa ◽  
2021 ◽  
Vol 502 (2) ◽  
pp. 191-207
Author(s):  
SHIVANI KASHYAP ◽  
CHANDAN KUMAR SAHU ◽  
ROHIT KUMAR VERMA ◽  
LAL BABU CHAUDHARY
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Seed Coat ◽  
Morphological Plasticity ◽  
Morphological Characters ◽  
Individual Species ◽  
Large Size ◽  
The Individual ◽  
Scanning Electron

Due to large size and enormous morphological plasticity, the taxonomy of the genus Astragalus is very complex and challenging. The identification and grouping of species chiefly based on macromorphological characters become sometimes difficult in the genus. In the present study, the micromorphology of the seeds of 30 species belonging to 14 sections of Astragalus from India has been examined applying scanning electron microscopy (SEM) along with light microscopy (LM) to evaluate their role in identification and classification. Attention was paid to colour, shape, size and surface of seeds. The overall size of the seeds ranges from 1.5–3.2 × 0.8–2.2 mm. The shape of the seeds is cordiform, deltoid, mitiform, orbicular, ovoid and reniform. The colour of seeds varies from brown to blackish-brown to black. Papillose, reticulate, ribbed, rugulate and stellate patterns were observed on the seed coat surface (spermoderm) among different species. The study reveals that the seed coat ornamentations have evolved differently among species and do not support the subgeneric and sectional divisions of the genus. However, they add an additional feature to the individual species, which may help in identification in combination with other macro-morphological features.

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