The Breeding Systems of Three Cooccurring Legumes: Dillwynia hispida, Dillwynia uncinata and Pultenaea densifolia (Leguminosae, Papilionoideae)

1990 ◽  
Vol 38 (2) ◽  
pp. 207 ◽  
Author(s):  
CL Gross
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Experiments ◽  
Fruit Set ◽  
Seed Set ◽  
Breeding Systems ◽  
High Pollen ◽  
Pollen Vectors ◽  
Esterase Production ◽  
Scanning Electron

The breeding systems of Dillwynia hispida Lindley, D. uncinata (Turcz.) J. Black and Pultenaea densifolia F. Muell. were determined using glasshouse trials and field experiments. Each species is self-incompatible and thus relies on pollen vectors to effect seed-set. Calculations of pollen-ovule ratios are compatible with this conclusion. Increase in the age of pollen led to a decline in fruit-set, which was more pronounced in Dillwynia uncinata than D. hispida or P. densifolia. In this study, Pultenaea densifolia pollen was never more than 60% viable which may explain the extremely high pollen-ovule ratio of this species. In all three species, esterase production on stigmas implied that they were fully receptive by day 3 of flowering. Stigma morphologies were assessed by scanning electron microscopy and the results used to discuss their incompatibility mechanisms.

scholarly journals Slippery flowers as a mechanism of defence against nectar-thieving ants

2020 ◽  
Author(s):  
Kazuya Takeda ◽  
Tomoki Kadokawa ◽  
Atsushi Kawakita
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Experiments ◽  
Epicuticular Wax ◽  
Pollinator Behaviour ◽  
Epicuticular Wax Crystals ◽  
Experimental Introduction ◽  
Floral Characters ◽  
Wax Crystals ◽  
Scanning Electron

AbstractBackground and AimsThe great diversity of floral characters among animal-pollinated plants is commonly understood as the result of coevolutionary interactions between plants and pollinators. Floral antagonists, such as nectar thieves, also have the potential to exert selection on floral characters, but adaptation against floral antagonists has attracted comparatively little attention. We found that the corollas of hornet-pollinated Codonopsis lanceolata (Campanulaceae) and the tepals of bee-pollinated Fritillaria koidzumiana (Liliaceae) are slippery to nectar-thieving ants living in the plant’s habitat; because the flowers of both species have exposed nectaries, slippery perianths may function as a defence against nectar-thieving ants.MethodsWe conducted a behavioural experiment and observed perianth surface microstructure by scanning electron microscopy to investigate the mechanism of slipperiness. Field experiments were conducted to test whether slippery perianths prevent floral entry by ants, and whether ant presence inside flowers affects pollination.Key ResultsScanning electron microscopy observations indicated that the slippery surfaces were coated with epicuticular wax crystals. The perianths lost their slipperiness when wiped with hexane. Artificial bridging of the slippery surfaces using non-slippery materials allowed ants to enter flowers more frequently. Experimental introduction of live ants to the Codonopsis flowers evicted hornet pollinators and shortened the duration of pollinator visits. However, no differences were found in the fruit or seed sets of flowers with and without ants.ConclusionsSlippery perianths, most likely based on epicuticular wax crystals, prevent floral entry by ants that negatively affect pollinator behaviour. Experimental evidence of floral defence based on slippery surfaces is rare, but such a mode of defence may be widespread amongst flowering plants.

scholarly journals Floral polymorphism and scanning electron microscopy determination in relation to climatic influence on Solanum nigrum L.

2020 ◽  
Vol 12 (2) ◽  
pp. 289-300
Author(s):  
Chandra KANTA ◽  
Ishwar P. SHARMA
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Reproductive Biology ◽  
Fruit Set ◽  
Floral Morphology ◽  
Solanum Nigrum ◽  
Climatic Effects ◽  
Climatic Influence ◽  
Solanum Nigrum L ◽  
Scanning Electron

Growing concern about climatic influence on plants reproductive biology leads to a recent surge. Climate affects directly floral morphology of plants on this basis current study summarizes climatic effects on floral or reproductive biology of Solanum nigrum L. Effect of summer, rainy and winter seasons were recorded on floral morphology, pollens viability & germination, pollen tube growth, fruit-set percentage during investigations which were subjected to one factorial analysis of variance (ANOVA) and least significant differences at p < 0.05. Climatic conditions affect floral morphology and produce polymorphism in specific conditions. In rainy and winter seasons, polymorphism was recorded in petals, stamens and pistil which is a first record of climatic influence on polymorphism. Rainy season reported for their maximum flowers numbers which promote a huge fruit-set percentage in open pollination as compared with self and cross pollination. This study confirms the effect of various climates on different floral parts which produce polymorphism along with growth, germination, length, etc. Scanning Electron Microscopy (SEM) study indicated the climatic variations on microscopic observations.

Stigma and Style Morphology in Relation to Taxonomy and Breeding Systems in Eucalyptus and Angophora (Myrtaceae)

1986 ◽  
Vol 34 (5) ◽  
pp. 569 ◽  
Author(s):  
DJ Boland ◽  
M Sedgley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Outer Surface ◽  
Breeding Systems ◽  
Cohesive Group ◽  
Varying Length ◽  
Scanning Electron

The stigma and style of 94 species of Eucalyptus and two species of Angophora were studied by scanning electron microscopy and/or light microscopy. All species had papillate stigmas and a stylar canal of varying length. Angophora species had mop-like stigmas with long papillae that were very similar in appearance to those of the red bloodwood group of the Corymbia, e.g. E. gummifera. The spotted gum group of the Corymbia had mop-like stigmas with short papillae and the yellow bloodwoods had tapered stigmas. The latter group was also charaderised by an extremely thick cuticle on the outer surface of the style, over 100 �m in thickness in E. watsoniana. All species in Blakella had tapered stigmas with a lobed surface and relatively few short papillae. The stylar canal had no cuticle in E. papuana. Eudesmia is a variable subgenus with E. erythrocorys unusual in having long multicellular papillae. Most Symphyomyrtus species had blunt or pinhead-shaped lobed stigmas with a heavily cutinised stylar canal. E. deglupta and E. microcorys did not conform to this pattern and had mop-shaped stigmas with long papillae. Monocalyptus species had blunt stigmas with few papillae and hollow styles and appeared to form a cohesive group. On the basis of stigma and style morphology Angophora is more similar to Corymbia than to Blakella. E. deglupta and E. microcorys are distinct from other Symphyomyrtus species studied. E. trachyphloia and E. jacobsiana are more similar to E. gummifera than to E. watsoniana or other yellow bloodwoods.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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).

Spontaneous Cataract in Nude Athymic Mice

1977 ◽  
Vol 35 ◽  
pp. 512-513
Author(s):  
Ronald H. Bradley ◽  
R. S. Berk ◽  
L. D. Hazlett
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Nude Mouse ◽  
Cellular Immunity ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Athymic Mice ◽  
Transmission Microscopy ◽  
Mouse Lens ◽  
Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Microbulldozing and Microchiseling

1969 ◽  
Vol 27 ◽  
pp. 134-135
Author(s):  
J.N. Ramsey ◽  
D.P. Cameron ◽  
F.W. Schneider
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Material Handling ◽  
Microprobe Analysis ◽  
Foreign Matter ◽  
Specific Location ◽  
Potential Problems ◽  
Knoop Indenter ◽  
Scanning Electron ◽  
Microhardness Tester

As computer components become smaller the analytical methods used to examine them and the material handling techniques must become more sensitive, and more sophisticated. We have used microbulldozing and microchiseling in conjunction with scanning electron microscopy, replica electron microscopy, and microprobe analysis for studying actual and potential problems with developmental and pilot line devices. Foreign matter, corrosion, etc, in specific locations are mechanically loosened from their substrates and removed by “extraction replication,” and examined in the appropriate instrument. The mechanical loosening is done in a controlled manner by using a microhardness tester—we use the attachment designed for our Reichert metallograph. The working tool is a pyramid shaped diamond (a Knoop indenter) which can be pushed into the specimen with a controlled pressure and in a specific location.

A New Image Processing Technique for STEM

1974 ◽  
Vol 32 ◽  
pp. 432-433
Author(s):  
Yasushi Kokubo ◽  
Hirotami Koike ◽  
Teruo Someya
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Elastic Scattering ◽  
Field Emission ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Energy Analyzer ◽  
Scanning Microscope ◽  
Scanning Electron

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.

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