Fine structural observations on substances attributable to Ceratocystis ulmi in American elm and aspects of host cell disturbances

1978 ◽  
Vol 56 (20) ◽  
pp. 2550-2566 ◽  
Author(s):  
G. B. Ouellette
Keyword(s):  
Host Cell ◽  
Cell Walls ◽  
Parenchyma Cell ◽  
Dutch Elm Disease ◽  
Similar Material ◽  
Fungal Cell ◽  
Fibrillar Material ◽  
American Elm ◽  
Vessel Walls ◽  
Parenchyma Cell Walls

Plugging of certain vessels may occur in elm shortly after inoculation with the Dutch elm disease pathogen, Ceratocystis ulmi (Buism.) C. Moreau. Plugging components include fibrillar material of varying density and fungal cells traceable mostly to inoculated spores. Some material is similar to fungal cell contents, and indications of extrusion of the latter through ruptured or unruptured walls were obtained. Other material is also attributable to disintegrating fungal walls. Radioautographs obtained from samples treated with [6-3H]thymidine indicate significant labeling of fungal cell contents and of similar material, free.Similar fibrillar material, some labeled, is present within pit membranes, in adjacent parenchyma cell walls, and in periplasmic areas associated with retraction of the plasmalemma and with other cytoplasmic disturbances. Host vessel walls are also altered in the presence of some fibrillar material but apparently release only limited amounts of disintegration products into vessels.The possible implications of these observations are discussed in relation to current hypotheses on wilt diseases.

MICROSTRUCTURE ANALYSIS OF MOSO BAMBOO (Phyllostachys pubescens MAZEL) SURFACE AFTER UV RADIATION

2019 ◽  
Vol 27 (01) ◽  
pp. 1950090
Author(s):  
HAIXIA YU ◽  
XIN PAN ◽  
WEIMING YANG ◽  
WENFU ZHANG ◽  
XIAOWEI ZHUANG
Keyword(s):  
Uv Radiation ◽  
Cell Walls ◽  
Uv Light ◽  
Parenchyma Cell ◽  
Moso Bamboo ◽  
Thick Wall ◽  
Phyllostachys Pubescens ◽  
Thin Wall ◽  
Intercellular Spaces ◽  
Parenchyma Cell Walls

Bamboo material is widely used in outdoor applications. However, they are easily degraded when exposed to sunlight, their smooth surface will gradually turn to rough, and small cracks will appear and finally develop to large cracks. The paper presents a first-time investigation on the microstructure changes in the tangential section of Moso bamboo (Phyllostachys pubescens Mazel) radiated by artificial UV light. The results showed that the cracks mainly appeared at intercellular spaces of fibers where lignin content was high, the parenchyma cell walls and neighbor pits where the cell wall was very thin and more vulnerable than the other parts. In addition, the part of raised area and pit cavity tended to absorb more UV light radiation and showed more and larger cracks than the otherwhere. Cracks at the intercellular spaces of fibers were larger and bigger than those on the parenchyma cell walls. The cracks on the pits of the parenchyma cell walls normally appeared at one pit and then extended to the several surrounding pits. Bordered pits cavity showed more and larger cracks than the pits on the thin wall cells. The simple pits on the thick wall cells and the fiber cells were unaffected by UV radiation.

Isolation of rice dwarf mutants with ectopic deposition of phenolic components including lignin in parenchyma cell walls of internodes

2011 ◽  
Vol 30 (12) ◽  
pp. 2195-2205 ◽  
Author(s):  
Kanna Sato ◽  
Asuka Kawamura ◽  
Tsukasa Obara ◽  
Shinya Kawai ◽  
Shinya Kajita ◽  
...  
Keyword(s):  
Cell Walls ◽  
Parenchyma Cell ◽  
Phenolic Components ◽  
Parenchyma Cell Walls

Xylem parenchyma cell walls lack a gravitropic response in conifer compression wood

Planta ◽  
2015 ◽  
Vol 242 (6) ◽  
pp. 1413-1424 ◽  
Author(s):  
Lloyd A. Donaldson ◽  
B. Nanayakkara ◽  
K. Radotić ◽  
D. Djikanovic-Golubović ◽  
A. Mitrović ◽  
...  
Keyword(s):  
Cell Walls ◽  
Compression Wood ◽  
Parenchyma Cell ◽  
Xylem Parenchyma ◽  
Gravitropic Response ◽  
Xylem Parenchyma Cell ◽  
Parenchyma Cell Walls

Histochemistry and UV-microspectrometry of cell walls of untreated and ammonia-treated barley straw

1998 ◽  
Vol 78 (3) ◽  
pp. 437-443 ◽  
Author(s):  
Masakazu Goto ◽  
Keiji Takabe ◽  
Isao Abe
Keyword(s):  
Absorption Spectra ◽  
Cell Walls ◽  
Spring Barley ◽  
Parenchyma Cell ◽  
Water Soluble ◽  
Barley Straw ◽  
Ir Absorption ◽  
Ammonia Treatment ◽  
Vessel Walls ◽  
Lignin Structure

Histochemical staining reactions with acid phloroglucinol and ultraviolet (UV) absorption spectra of the individual cell walls in spring barley straw (Hordeum vulgare L.) were investigated in combination with spectrometric measurements of the dioxane-water soluble lignin. Changes in lignin structure of barley straw with ammonia treatment were also investigated. Parenchyma and metaxylem vessel walls in untreated straw stained red with acid phloroglucinol and had higher absorbances around 550 nm than did epidermis and sclerenchyma cell walls, being consistent with the λmax of coniferylaldehyde. Following a reductive treatment, the lignins isolated from untreated barley straw showed an increase in UV absorbance at 280 nm and a decrease in that around 320 nm. These regions in UV and IR absorption spectra are assigned to conjugated carbonyl groups as shown by the narrowing of the IR absorption band at 1660 cm−1, and this was consistent with the staining observation of the specific tissue walls. UV microspectrometry indicated that parenchyma cell walls were much less lignified tissues than metaxylem and protoxylem vessel walls and probably epidermal cell walls. The lignins isolated from untreated and ammonia-treated straw had similar values for empirical formulae of the C9 units, phenolic hydroxyl and methoxyl group contents, and molecular weight, although the lignin of ammonia-treated straw had a slightly higher contents of nitrogen and hydrogen. The IR bands of 1730–1680 cm−1 in ammonia-treated straw lignin also disappeared. Therefore, ammonia appeared to react with the carbon atoms of the propane side-chain. Key words: Ammonia treatment, barley straw, lignin distribution, lignin structure, staining with acid phloroglucinol, ultraviolet microspectrometry

On tylosis ultrastructure in Quercus cerris L.

Holzforschung ◽  
2019 ◽  
Vol 73 (12) ◽  
pp. 1121-1123
Author(s):  
Mihály Bariska ◽  
Zoltán Pásztory ◽  
Zoltán Börcsök
Keyword(s):  
Cell Walls ◽  
Parenchyma Cell ◽  
Primary Wall ◽  
Contact Areas ◽  
Turkey Oak ◽  
Quercus Cerris ◽  
Wall Openings ◽  
Vestured Pits ◽  
Granular Surface ◽  
Parenchyma Cell Walls

Abstract A study of tylosis in European Turkey oak (Quercus cerris L.) shows correspondences in the formation of tyloses and of regular cell walls. The outer tylosis wall has a smooth, granular surface with simple perforations analogous to that of the primary wall of ordinary cells. The underlying wall stratum shows parallel oriented macro-fibrils, normally found in the secondary walls of regular cells. At the contact areas of tyloses, stabilizing seams can be observed. Various types of wall openings such as simple pits, blind pits and vestured pits were present. Also tylosis division was detected. The characteristics of parenchyma cell walls can be re-discovered in tyloses.

Fine structure of the extracellular sheath and cell walls inOphiostoma novo-ulmigrowing on various substrates

1999 ◽  
Vol 45 (7) ◽  
pp. 582-597 ◽  
Author(s):  
G B Ouellette ◽  
H Chamberland ◽  
A Goulet ◽  
M Lachapelle ◽  
J -G Lafontaine
Keyword(s):  
Cell Walls ◽  
Surrounding Medium ◽  
Wall Layer ◽  
Dutch Elm Disease ◽  
Fungal Cell ◽  
Parallel Structures ◽  
Cell Components ◽  
Fungal Dna ◽  
Standard Fixation ◽  
Electron Lucent

The presence of microfilamentous-like structures of tubular appearance (MFS) in cell walls and extracellular sheath material (ES) in a number of isolates of Ophiostoma novo-ulmi Brasier grown on various substrates and following various treatments is reported. Standard fixation or high-pressure freezing methods were used, and cytochemical tests were carried out to detect fungal and host wall components and, in some cases, fungal DNA. In some cases, serial 0.2-μm-thick sections were examined at 120 kV and tilted to obtain stereoscopic images. Whether the fungal cell walls were thick and composed of an outer opaque and inner more electron-lucent layers, or thin and barely perceptible, MFS were observed to extend from the cell cytoplasm as parallel structures across the walls into the surrounding medium, including host cell components in infected elm tissues. MFS were associated (in samples from inoculated trees) with cleavage and desquamation of fungal walls. ES and MFS did not label for cellulose or chitin, but generally labelled slightly for β-(1-3)-glucan and mannose, and strongly for galactose. Only the lucent, inner fungal wall layer labelled for chitin and cellulose. DNA labelling was confined to nuclei and mitochondria in fungal cells from cultures on agar medium; in cells from cultures on millipore membranes, it was pronounced over imprecisely delimited cell regions. The possible ontogeny of MFS components and their importance are discussed. Key words: chitin, Dutch elm disease, fungal fimbriae, fungal walls, gold-complexed probes, microfilamentous structures (MFS).

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