Methods of onion seed preparation for scanning electron microscope studies of the seed coat

1991 ◽  
Vol 18 (2) ◽  
pp. 207-208 ◽  
Author(s):  
Yasseen Mohamed-Yasseen ◽  
Birute P. Jakstys ◽  
Walter E. Splittstoesser
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Seed Coat ◽  
Onion Seed ◽  
Scanning Electron

scholarly journals Seed micromorphological study on endemic and subendemic species of Veronica L. (Plantaginaceae Juss.) in Iran

2019 ◽  
Vol 26 (2) ◽  
pp. 315-324
Author(s):  
Soghra Ramzi ◽  
Shahryar Saedi-Mehrvarz
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Seed Coat ◽  
Seed Morphology ◽  
Seed Shape ◽  
Sem Micrographs ◽  
Qualitative And Quantitative ◽  
Quantitative Characters ◽  
Micromorphological Characters ◽  
Scanning Electron

Seed morphology of 12 Iranian endemic and subendemic species of Veronica was studied using scanning electron microscope (SEM). Seven qualitative and quantitative characters were measured using SEM micrographs and stereomicroscopy. The seed shape of most species is ovate and plano-convex. The size of seeds ranges from 1.25 x 0.75 mm in V. khorassanica to 2.5 x 1.75 mm in V. viscosa Boiss. The ornamentation of seed coat is reticulate-verrucate in V. khorassanica, V. czerniakowskiana, V. mazanderanae and V. rubrifolia, reticulate-rugate in V. acrotheca, V. aucheri, V. viscosa and V. intercedens, rugose in V. microcarpa, V. chionantha and V. rechingeri, and reticulate-porate in V. gaubae. The testa cells are polygonal in ten species and irregular in two species. Micromorphological characters of seeds are useful in specific and subspecific delimitations of Iranian Veronica.

A scanning electron microscope study of Cucurbita maxima seed coat structure

1973 ◽  
Vol 51 (10) ◽  
pp. 1711-1714 ◽  
Author(s):  
John N. A. Lott
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Seed Coat ◽  
Three Dimensional ◽  
Deposition Process ◽  
Dimensional Structure ◽  
Cucurbita Maxima ◽  
Spongy Parenchyma ◽  
Scanning Electron Microscope Study ◽  
Scanning Electron

The examination of the seed coat of Cucurbita maxima with the scanning electron microscope provided information about the three-dimensional structure of the seed coat cells. The lumpy appearance of the spongy parenchyma cells indicated that localized wall growth must have occurred. Also of particular interest were the reticulate secondary wall thickenings in the hypodermal and spongy parenchyma regions of the seed coat. The developing squash seed coat may prove to be a good model system in which to study the cell wall deposition process.

scholarly journals New Data on Seed Coat Micromorphology of Several Impatiens spp. from Northeast India

2020 ◽  
Vol 89 (3) ◽  
Author(s):  
Agnieszka Rewicz ◽  
Wojciech Adamowski ◽  
Souravjyoti Borah ◽  
Rajib Gogoi
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Surface Structure ◽  
Seed Coat ◽  
Northeast India ◽  
Epidermal Cells ◽  
Diagnostic Character ◽  
Lack Of Information ◽  
Metric Traits ◽  
Scanning Electron

This study aimed to analyze the seed coat structure of nine species from the genus <em>Impatiens </em>from Northeast India. A review of the available literature showed a scarcity of data on seed sizes and shapes, as well as a complete lack of information on the ultrastructure of seeds from five taxa of <em>Impatiens </em>determined with a scanning electron microscope (SEM). Photographs of the surface structure of seeds from the analyzed species were taken using an SEM and, from these, we measured the length and width of the seeds. The results showed differences in the seed ultrastructure and metric traits within the studied taxa. Based on the ornamentation of the epidermal cells, we distinguished three morphological types: protrusive, granulate, and reticulate. The seeds of the investigated species had ellipsoid, subellipsoid, or subspheroid shapes. Their lengths and widths ranged from 1.2 to 3.6 mm and 0.7 to 2.1 mm, respectively. The results of the study showed that the ultrastructures of <em>Impatiens </em>seeds are different among taxa and for some species can be used as a diagnostic character for their identification.

Morphological Development and Germination of Dwarf Spikerush (Eleocharis coloradoensis)

Weed Science ◽  
1979 ◽  
Vol 27 (4) ◽  
pp. 380-385 ◽  
Author(s):  
Richard R. Yeo
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Seed Coat ◽  
Aquatic Plant ◽  
Water Soluble ◽  
Morphological Development ◽  
Shoot Apices ◽  
Cotyledonary Sheath ◽  
Scanning Electron

Dwarf spikerush [Eleocharis coloradoensis(Britt.) Gilly] is an aquatic plant that will displace waterweeds. It was studied to obtain information that will help to manage unwanted vegetation in natural aquatic situations. The morphology of seed and tubers was examined at the light- and scanning-electron microscope levels. Inflorescences were found to bear 3 to 12 florets that matured acropetally. The pericarp was made up largely of rows of annulated cells covered with a water-soluble, waxlike substance that leached away when stored in water at 4 to 6 C. The seed coat consisted of three layers. Each layer contained lipids, giving evidence that they were composed of cutin. When the seed germinated, the cotyledonary sheath emerged first, followed by the culms. Tubers formed and matured in about 30 days. The shoot apices of tubers each had two buds that were protected by five to seven overlapping membraneous leaf scales. When tubers sprouted the longest bud grew first. The second bud contained the culm meristem.

The Alteration of the Pore Spaces in Sandstones

1973 ◽  
Vol 31 ◽  
pp. 210-211
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
The Other ◽  
Coarse Grained ◽  
Depositional Fabric ◽  
Soluble Components ◽  
Scanning Electron ◽  
Shape And Size

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.

The Broad Applications of the Scanning Electron Microscope

1969 ◽  
Vol 27 ◽  
pp. 20-21
Author(s):  
C. T. Nightingale ◽  
S. E. Summers ◽  
T. P. Turnbull
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscopy ◽  
Surface Topography ◽  
Great Depth ◽  
Resolving Power ◽  
Depth Of Field ◽  
Pictorial Representations ◽  
Scanning Electron

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.

Observability of Very Thick Specimen by Using Transmission Scanning Electron Microscope

1971 ◽  
Vol 29 ◽  
pp. 26-27
Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike
Keyword(s):  
Electron Microscope ◽  
Image Quality ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Image Contrast ◽  
Objective Lens ◽  
Thick Specimen ◽  
Transmission Electron ◽  
Scanning Electron

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.

Resolution of a Transmitted Electron Image Formed by A Scanning Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 386-387
Author(s):  
S. Takashima ◽  
H. Hashimoto ◽  
S. Kimoto
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Objective Lens ◽  
Specimen Thickness ◽  
Probe Diameter ◽  
Transmission Electron ◽  
Electron Image ◽  
Conventional Transmission Electron Microscope ◽  
Scanning Electron

The resolution of a conventional transmission electron microscope (TEM) deteriorates as the specimen thickness increases, because chromatic aberration of the objective lens is caused by the energy loss of electrons). In the case of a scanning electron microscope (SEM), chromatic aberration does not exist as the restrictive factor for the resolution of the transmitted electron image, for the SEM has no imageforming lens. It is not sure, however, that the equal resolution to the probe diameter can be obtained in the case of a thick specimen. To study the relation between the specimen thickness and the resolution of the trans-mitted electron image obtained by the SEM, the following experiment was carried out.

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