Early stages of infection of rapeseed petals and leaves by Sclerotinia sclerotiorum revealed by scanning electron microscopy

1995 ◽  
Vol 44 (1) ◽  
pp. 22-30 ◽  
Author(s):  
I. JAMAUX ◽  
B. GELIE ◽  
C. LAMARQUE
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sclerotinia Sclerotiorum ◽  
Early Stages ◽  
Scanning Electron

Developmental morphology of the flower of Anthurium jenmanii: a new element in our understanding of basal Araceae

Botany ◽  
2008 ◽  
Vol 86 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Floral Development ◽  
Developmental Morphology ◽  
Calcium Oxalate Crystals ◽  
Stages Of Development ◽  
Early Stages ◽  
Floral Primordia ◽  
Scanning Electron

The early stages of development of the inflorescence of Anthurium jenmanii Engl. were examined using scanning electron microscopy. The inflorescence of A. jenmanii consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The gynoecium consists of two carpels. The floral primordia are first initiated on the lower portion of the inflorescence, they then increase in size and appear as transversely extended bulges. The two lateral tepals are the first organs to be initiated, followed shortly thereafter by the two median tepals. The two lateral stamens are initiated first, directly opposite the lateral tepals, and are followed by two median stamens initiated directly opposite the median tepals. A two-lobed stigma is clearly visible during the early stages of development of the gynoecium. On some of the young inflorescences, all floral parts were covered by extracellular calcium oxalate crystals. The release of these prismatic crystals occurs before the stamens and petals have reached maturity. The mode of floral development observed in Anthurium has similarities with that reported for Gymnostachys . However, contrary to Gymnostachys, the development of the flower of A. jenmanii is not unidirectional.

scholarly journals Architectural Development of Inflorescence in Hydrangea macrophylla cv. Hermann Dienemann

HortScience ◽  
2008 ◽  
Vol 43 (2) ◽  
pp. 361-365 ◽  
Author(s):  
Gilles Galopin ◽  
Sandrine Codarin ◽  
Jean-Daniel Viemont ◽  
Philippe Morel
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Inflorescence Development ◽  
Schematic Representation ◽  
Early Stages ◽  
Hydrangea Macrophylla ◽  
Floral Differentiation ◽  
Architectural Development ◽  
Scanning Electron

Architectural development of inflorescence in Hydrangea macrophylla cv. Hermann Dienemann was observed using scanning electron microscopy. The study of inflorescence morphogenesis shows that the architecture is of the dichasial type. The first two orders of branching are initiated from a dichasial branching without floral differentiation. The following orders present floral differentiation. They determine the formation of small units through the development of composite dichasium into biparous and uniparous cymes. This research makes it possible to establish a schematic representation of the first phases of inflorescence development and to define early stages of inflorescence morphogenesis.

Comparison of Scanning Electron Microscopy and Light Microscopy for the Diagnosis of Early Stages of Brown Rot Wood Decay

IAWA Journal ◽  
1993 ◽  
Vol 14 (3) ◽  
pp. 219-226 ◽  
Author(s):  
W. Wayne Wilcox
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Cell Walls ◽  
Wood Decay ◽  
Brown Rot ◽  
Early Stages ◽  
Polarised Light ◽  
Scanning Electron

As part of a larger study of the microscopical characteristics useful in diagnosing early stages of decay, an opportunity was created to compare the ability of light microscopy (LM) and scanning electron microscopy (SEM) to image these features. Although most features could be imaged by both technologies, imaging was much easier in the SEM because it was being used at the low end of its resolution and magnification capability while the LM was near the high end of its limitations. One important feature which could not be imaged in SEM was the earliest attack on the cell walls, a feature which was visible under polarised light in the LM.

Early stages of initiation of two types of leaves in Thuja occidentalis (eastern white cedar)

2004 ◽  
Vol 82 (5) ◽  
pp. 598-606 ◽  
Author(s):  
Christian Lacroix ◽  
Denis Barabé ◽  
Bernard Jeune
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Apical Meristem ◽  
Leaf Primordia ◽  
Leaf Primordium ◽  
Thuja Occidentalis ◽  
White Cedar ◽  
Early Stages ◽  
Eastern White Cedar ◽  
Scanning Electron

The developmental morphology of shoots of Thuja occidentalis L. (eastern white cedar) was investigated using scanning electron microscopy to determine the pattern of initiation of two types of leaves characteristic of higher (third and above) order branches. The shoots of eastern white cedar are bilateral in symmetry and bear leaves in an orthogonal decussate phyllotactic pattern. The shoot system is further characterized by the presence of two alternating and morphologically different pairs of leaves that constitute the basic repeating pattern of the shoot apical meristem (SAM). At maturity the dimorphism between leaf types is marked. Leaves in one plane are wide and flat in comparison with narrower and cup-shaped leaves growing in a plane perpendicular to the other leaf type. The early stages of development of each of the two types of leaves were compared using scanning electron microscopy. During the earliest visible stages of initiation (primordial crest), cup-shaped and flat leaves are very similar in morphology. As individual leaf primordia become more easily delimited as structures by the presence of a furrow between the SAM and the leaf, they differ in terms of width. As they develop further and begin to cover the SAM, the two leaf types are distinguishable morphologically (flat vs. cup shaped). Quantitative parameters such as diameter of the SAM, angle of insertion of individual leaves, and size of leaf primordia (in both a tangential and perpendicular plane) were measured on three categories of leaves: stage 1, earliest visible stage of initiation; stage 2, delineation of leaf primordium from SAM by furrowing; stage 3, leaf primordium partially covering SAM. These measurements corroborate our morphological observations, which show that during early stages of development, flat and cup-shaped leaves are morphologically similar and they diverge in their pattern of development postinitiation, especially as far as leaf width and thickness are concerned. Our results also suggest that the size and shape of the apex goes through a "repeating" cycle and is related to the type of primordium that will be initiated.Key words: Thuja occidentalis, eastern white cedar, leaf development, shoot apical meristem, phyllotaxy, leaf dimorphism.

Morphological development of sclerotia by Sclerotinia sclerotiorum: a view from light and scanning electron microscopy

2014 ◽  
Vol 65 (2) ◽  
pp. 765-770 ◽  
Author(s):  
Claudia Ordóñez-Valencia ◽  
Ronald Ferrera-Cerrato ◽  
Rafael Emiliano Quintanar-Zúñiga ◽  
Cesar Mateo Flores-Ortiz ◽  
Guadalupe Judith Márquez Guzmán ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sclerotinia Sclerotiorum ◽  
Morphological Development ◽  
Scanning Electron

Early Stages of Recrystallization in ECAP-Deformed AA1050 Alloy Investigated by SEM Orientation Mapping

2013 ◽  
Vol 753 ◽  
pp. 267-270 ◽  
Author(s):  
Jagoda Poplewska ◽  
Henryk Paul ◽  
Katarzyna Berent
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Angle ◽  
Early Stages ◽  
Angular Pressing ◽  
Orientation Mapping ◽  
Purity Aluminium ◽  
Continuous Recrystallization ◽  
Equiaxed Grains ◽  
Scanning Electron

Early stages of recrystallization were observed for the technical purity aluminium alloy (AA1050). The samples were severely deformed by equal channel angular pressing and then annealed to obtain the state of partial recrystallization. The nucleation of new grains and the changes in ‘density’ of low- and high- angle boundaries were analysed using scanning electron microscopy equipped with high resolution EBSD system. After deformation in six passes along route A the alloy contained a structure of flat grains. On annealing, the structure coarsened and got transformed into nearly equiaxed grains by both discontinuous and continuous recrystallization. A particular role in the rise of nuclei and the structure spheroidization is attributed to migration of low-angle boundaries.

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