Studies in the genus Strossmayeria (Helotiales). 5. Conidia and conidiogenesis in Pseudospiropes: a light and electron microscope investigation

1985 ◽  
Vol 63 (2) ◽  
pp. 195-200 ◽  
Author(s):  
Teresita Iturriaga ◽  
Herbert W. Israel

Conidiogenesis and conidial morphology in two Pseudospiropes species, anamorphs of two unnamed Strossmayeria species, were studied using light microscopy and scanning electron microscopy, and for one of these, transmission electron microscopy. Conidiogenesis is clearly holoblastic. In these species there are approximately 10 cells per conidium, the apical and basal ones being darker than the others. A gel surrounds the conidium, and what probably is a gelatinous appendage is seen at its apex. The conidial wall is composed of at least eight layers, the exterior surface being distinctly poroid. There are columnar irregularities in the conidial walls. These morphological features have potential taxonomic importance.

Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

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).


Phytotaxa ◽  
2015 ◽  
Vol 207 (1) ◽  
pp. 135 ◽  
Author(s):  
Giovanni Raul Bogota ◽  
Carina Hoorn ◽  
Wim Star ◽  
Rob Langelaan ◽  
Hannah Banks ◽  
...  

Sabinaria magnifica is so far the only known species in the recently discovered tropical palm genus Sabinaria (Arecaceae). Here we present a complete description of the pollen morphology of this palm species based on light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We also made SEM-based comparisons of Sabinaria with other genera within the tribe Cryosophileae. Pollen grains of Sabinaria magnifica resemble the other genera in the heteropolar, slightly asymmetric monads, and the monosulcate and tectate exine with perforate surface. Nevertheless, there are some clear differences with Thrinax, Chelyocarpus and Cryosophila in terms of aperture and exine. S. magnifica differs from its closest relative, Itaya amicorum, in the exine structure. This study shows that a combination of microscope techniques is essential for the identification of different genera within the Cryosophileae and may also be a necessary when working with other palynologically less distinct palm genera. 


1985 ◽  
Vol 63 (4) ◽  
pp. 757-761 ◽  
Author(s):  
E. Untiedt ◽  
K. Müller

Lyophyllum palustre (Peck) Singer, a basidiomycete (Tricholomataceae) parasitizing Sphagnum, was examined for points of contact between hyphae and Sphagnum cells with the help of light microscopy, scanning electron microscopy, and transmission electron microscopy. Results indicate that the fungus attacks Sphagnum cells by penetrating cell walls and altering host cell protosplasm. In addition, the formation of additional partitioning cell walls in attacked living Sphagnum cells was observed.


1992 ◽  
Vol 70 (11) ◽  
pp. 2223-2232 ◽  
Author(s):  
S. J. Read ◽  
S.-Y. Hsieh ◽  
E. B. G. Jones ◽  
S. T. Moss ◽  
H. S. Chang

A collection of Paraliomyces lentiferus from Taiwan, Republic of China, is compared with that of the type description and examined at both scanning and transmission electron microscope levels as part of our review of the taxonomy of the marine Ascomycotina. Particular attention was devoted to the structure of the ascospore appendage. The ascospore wall comprises a mesosporium, an episporium, and a mucilaginous sheath (exosporium?) In addition, there is a single, gelatinous, lateral appendage adjacent to the central septum. The appendage comprises electron-opaque fibrils that in immature ascospores are connected to the ascospore wall via fine electron-opaque strands and larger electron-opaque aggregates of material. The origin of the appendage is discussed. Key words: ascospore, attachment, marine ascomycete, scanning electron microscopy, spore appendage, transmission electron microscopy.


Author(s):  
Miguel W. Fomés ◽  
Mario H. Burgos

During epididymal transit a head to head association of spermatozoa has been described in guinea pig, Loris and marsupials. In guinea pig they are permanent and androgen dependent. Other type of sperm association described in nonseasonal. mammals, adopt the stiape of dense masses of degenerating spermatozoa.In the present study a new transitory head to head association in rat spemiatozoa is described which appears at the end of the epididymal transit and dense masses of associated spennatozoa in degeneration similar to those described in the literature. The sperm samples were obtained by puncture of the 3 main epididymal regions. The emerging fluid drops were immediately suspended in a balanced salt solution, placed in a slide-cover slide chanber at 36°C, and observed and recorded with a video equipment. Other drops of epididymal fluid were fixed in Mollenhauer (1976) and processed for light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).


Author(s):  
Janet Hearn Woodward

Nocardia polychromogenes is an aerobic, gram (+), non-motile, partially acid-fast actinomycete with primary mycelia that fragment into bacillary and coccoid elements.For scanning electron microscopy, N. polychromogenes culture strain Waksman 3409-A was grown on Potato Dextrose Agar at 25 C for 12-72 h. Five mm2 sections of the colonies, including portions of the interior and perimeter were fixed by exposure to osmium fumes for 16-24 h and air dried for 2 h. Specimens, mounted on stubs and sputter coated with gold, were viewed in a Cambridge Stereoscan Mark II scanning electron microscope. For transmission electron microscopy, the organism was grown on Potato Dextrose Agar at 25 C for 12-32 h. Whole colonies, 1-2 mm in diameter, were fixed by exposure to osmium fumes for 24 h. After suspension in noble agar, cells taken from the periphery of the fixed colonies were stained with 0. 5% uranyl acetate made in acetate-veranol buffer.


1989 ◽  
Vol 67 (1) ◽  
pp. 116-120 ◽  
Author(s):  
Susan M. Wood ◽  
William Newcomb ◽  
David Nelson

Root nodules of Cercocarpus ledifolius Nutt. (mountain mahogany) were studied by light microscopy, scanning electron microscopy, and transmission electron microscopy to confirm the bacterial nature of the microsymbiont and to determine the morphology of the symbiotic vesicles. The microsymbiont is an actinomycete having two morphologies: septate hyphae (ca. 0.5 μm diam.) and ovoid- or elliptical-shaped nonseptate symbiotic vesicles (2.8 × 3.9 μm). Many of the symbiotic vesicles contain a single, electron-dense ovoid- or spherical-shaped structure, measuring 0.26 μm, whose function is unknown. The actinomycete is surrounded by a capsule that has electron-dense droplets in regions near hyphae. No spores or sporangia were observed in these nodules.


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