A scanning electron microscope study of the development and surface features of floral organs of tomato (Lycopersicon esculentum)

1984 ◽  
Vol 62 (11) ◽  
pp. 2403-2413 ◽  
Author(s):  
K. N. Chandra Sekhar ◽  
V. K. Sawhney
Keyword(s):  
Lycopersicon Esculentum ◽  
Progressive Increase ◽  
Basal Region ◽  
Scanning Electron Microscope Study ◽  
Floral Organs ◽  
Surface Features ◽  
Staminal Tube ◽  
Floral Apex ◽  
Different Types ◽  
Scanning Electron

The initiation and development and the surface features of floral organs of tomato (Lycopersicon esculentum Mill.) were examined using scanning electron microscopy. After the transformation of the vegetative apex into the floral apex, the floral organs appeared in the following sequence: sepals, petals, stamens, and carpels. The pattern of initiation was helical for the sepals and simultaneous for petals, stamens, and carpels. There was a progressive increase in the diameter of the apex associated with the initiation of each whorl of organs. Following initiation, the sepal and petal primordia fused at the basal region by "zonal growth," but the cohesion of anthers to form a staminal tube occurred later in development and was achieved by the interlocking of epidermal hairs produced on the lateral and adaxial surfaces of anthers. Carpel primordia were produced at the circumference of the remaining meristem and were fused laterally early in development. Epidermal hairs of different types and frequencies were observed on the adaxial and abaxial surfaces of sepals and petals and on the adaxial and lateral surfaces of the anthers. In the gynoecium, hairs were present only on the lower half of the style and were absent on the ovary. Stomata were observed on the sepals, petals, and style, but not on the anthers or ovary. Raised stomata were present only on young developing sepals and the style and were absent on mature organs. Cuticular thickenings were also observed on the abaxial surfaces of sepals, petals, and stamens, but not on the gynoecium.

Seed coat morphology of some Turkish Campanula (Campanulaceae) species and its systematic implications

Biologia ◽  
2009 ◽  
Vol 64 (6) ◽  
Author(s):  
Tülay Akcin
Keyword(s):  
Electron Microscopy ◽  
Seed Coat ◽  
Common Type ◽  
Surface Features ◽  
Seed Surface ◽  
Different Types ◽  
Seed Coat Morphology ◽  
Scanning Electron

AbstractThe seed coat morphology of 10 Campanula species from Turkey, 3 of which are endemic, was studied using scanning electron microscopy. Characteristics of the seeds and their surface morphology were described and compared. Two different types were described based on seed surface features. The Type 1 seed surface was characterized by a reticulate pattern; only C. Olympica belonged to this type. The Type 2 seed surface had a striate testa and was the most common type. It included C. Lyrata subsp. lyrata, C. rapunculoides L. subsp. rapunculoides, C. glomerata L. subsp. hispida, C. involucrata, C. saxonorum, C. persicifolia, C. latiloba subsp. latiloba, C. lactiflora and C. Rapunculus L. var. lambertiana. However, some differences among these species were determined on the basis of their seed surface features at the microstructural level. These features were evaluated as possibly consistent parameters in the delimination of the Campanula taxa studied.

Scanning Electron Microscope Study of Surface Characteristics of Abrasive Materials

1974 ◽  
Vol 96 (3) ◽  
pp. 145-156 ◽  
Author(s):  
R. Komanduri ◽  
M. C. Shaw
Keyword(s):  
Chemical Properties ◽  
Surface Characteristics ◽  
Scanning Electron Micrographs ◽  
Physical And Chemical Properties ◽  
Scanning Electron Microscope Study ◽  
Abrasive Grains ◽  
Different Types ◽  
Physical And Chemical ◽  
Scanning Electron ◽  
And Chemical Properties

Scanning electron micrographs of different types of commercial abrasive grains used in grinding are discussed. Surface topography is found useful, along with other physical and chemical properties, in characterizing abrasive materials. The results of this study explain some of the differences in performance of several types of abrasive presently used in grinding practice.

scholarly journals Dental Wear: A Scanning Electron Microscope Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Luca Levrini ◽  
Giulia Di Benedetto ◽  
Mario Raspanti
Keyword(s):  
Current Knowledge ◽  
Human Teeth ◽  
Scanning Electron Microscope Study ◽  
Dental Wear ◽  
Dentinal Tubules ◽  
Etiological Factors ◽  
Specific Morphology ◽  
Lesion Type ◽  
Different Types ◽  
Scanning Electron

Dental wear can be differentiated into different types on the basis of morphological and etiological factors. The present research was carried out on twelve extracted human teeth with dental wear (three teeth showing each type of wear: erosion, attrition, abrasion, and abfraction) studied by scanning electron microscopy (SEM). The study aimed, through analysis of the macro- and micromorphological features of the lesions (considering the enamel, dentin, enamel prisms, dentinal tubules, and pulp), to clarify the different clinical and diagnostic presentations of dental wear and their possible significance. Our results, which confirm current knowledge, provide a complete overview of the distinctive morphology of each lesion type. It is important to identify the type of dental wear lesion in order to recognize the contributing etiological factors and, consequently, identify other more complex, nondental disorders (such as gastroesophageal reflux, eating disorders). It is clear that each type of lesion has a specific morphology and mechanism, and further clinical studies are needed to clarify the etiological processes, particularly those underlying the onset of abfraction.

A Scanning Electron Microscope Study of Washer-Dryer Abrasion in Textiie Fibers

1970 ◽  
Vol 28 ◽  
pp. 346-347
Author(s):  
Wilton R. Goynes
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Cotton Fabrics ◽  
Cross Linking ◽  
Scanning Electron Microscope Study ◽  
Durable Press ◽  
Transmission Electron ◽  
Different Types ◽  
Ultrathin Sections ◽  
Scanning Electron

The reaction of cellulose with certain cross-linking agents has produced cotton fabrics with outstanding durable press characteristics. However, many of these reactions decrease the natural abrasion resistance of the fiber. Wet abrasion and dry abrasion are known to produce different types of damage in the cotton fiber. It was of interest to determine whether such differences occur in the machine washing and drying of cotton fabrics. To study this problem, both untreated and cross-linked cotton fabrics were made into trouser cuffs, washed repeatedly and line dried, or machine dried until extensive damage had occurred. The two reacted fabrics studied had been treated with dimethyloldihydroxyethyleneurea and tris(l-aziridinyl) phosphine oxide. Cuene solubility tests on ultrathin sections of fibers from th ese fabrics observed with the transmission electron microscope indicated that the fibers were uniformly cross-linked throughout.

Regulation of the fusion of floral organs by temperature and gibberellic acid in the normal and solanifolia mutant of tomato (Lycopersicon esculentum)

1990 ◽  
Vol 68 (4) ◽  
pp. 713-718 ◽  
Author(s):  
K. N. Chandra Sekhar ◽  
V. K. Sawhney
Keyword(s):  
Lycopersicon Esculentum ◽  
Gibberellic Acid ◽  
Ammonium Chloride ◽  
Low Temperatures ◽  
Single Gene ◽  
Gibberellin Biosynthesis ◽  
Growth Substances ◽  
Apparent Effect ◽  
Floral Organs ◽  
Floral Apex

The flowers of a single gene homozygous recessive solanifolia (sf/sf) mutant of tomato (Lycopersicon esculentum) possess separate sepals, petals and stamens, and a gynoecium that consists of several carpels with separate styles. In contrast, in the normal tomato (cv. Pearson), floral organs of each whorl are either partially or completely fused. Different temperature conditions and gibberellic acid treatments had no effect on the ontogenetic fusion of sepals and petals of the mutant and normal flowers. However, low temperatures and gibberellic acid induced the separation of stamens and pistil in many of the normal flowers, and they enhanced the separation of carpels in mutant flowers. In contrast, high temperatures and 2-chlo-roethyltrimethyl ammonium chloride, an inhibitor of gibberellin biosynthesis, promoted the fusion of stamens and gynoecia of mutant flowers, but had no apparent effect on the normal flowers. The nonfusion of stamens and carpels, in both genotypes, was associated with an increase in the number of these organs, whereas their fusion was accompanied with a reduction in their number. It is proposed that the nonfusion of floral organs in the sf/sf mutant is partly related to changes in endogenous growth substances which, through an effect on the size of the floral apex, affect the number and fusion of stamens and carpels.

A Scanning Electron Microscope Study of Isolated Guard Cells

1973 ◽  
Vol 31 ◽  
pp. 454-455 ◽  
Author(s):  
P. Dayanandan ◽  
P. B. Kaufman
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Three Dimensional ◽  
Guard Cells ◽  
Scanning Electron Microscope Study ◽  
Psilotum Nudum ◽  
Subsidiary Cells ◽  
Welwitschia Mirabilis ◽  
Cycas Revoluta ◽  
Scanning Electron

A three dimensional appreciation of the guard cell morphology coupled with ultrastjuctural studies should lead to a better understanding of their still obscure dynamics of movement. We have found the SEM of great value not only in studies of the surface details of stomata but also in resolving the structures and relationships that exist between the guard and subsidiary cells. We now report the isolation and SEM studies of guard cells from nine genera of plants.Guard cells were isolated from the following plants: Psilotum nudum, four species of Equisetum, Cycas revoluta, Ceratozamia sp., Pinus sylvestris, Ephedra cochuma, Welwitschia mirabilis, Euphorbia tirucalli and Allium cepa.

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.

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