The aggregation of wheat rhizoplane fibrils and the accumulation of soil-bound cations

1975 ◽  
Vol 53 (16) ◽  
pp. 1729-1735 ◽  
Author(s):  
Gary G. Leppard ◽  
S. Ramamoorthy
Keyword(s):  
Cell Walls ◽  
Solid Phase ◽  
Root Surface ◽  
Surface Structures ◽  
Soil Environment ◽  
Wheat Roots ◽  
Root Cells ◽  
Contact Exchange ◽  
Cation Uptake ◽  
Fibril Aggregates

Some surface materials of roots can accumulate bound cations from the soil environment by contact exchange. This paper describes the physical relationships between rhizoplane fibril aggregates and other root surface structures in the zone of active cation uptake. Sheets and tufts of rhizoplane fibrils project from wheat roots and establish a discrete and intimate physical connection between root cell walls and the solid phase of the soil environment. These aggregates of fibrils may provide a direct channel for the movement of soil-bound cations to the surface of root cells. Consideration is given to a possible mechanism of extraction of soil-bound cations by rhizoplane fibrils and the transfer of these cations to the walls of cells actively engaged in cation uptake.

Characterization of machined polystyrene foam

1989 ◽  
Vol 47 ◽  
pp. 372-373
Author(s):  
C. W. Price ◽  
E. F. Lindsey ◽  
R. M. Franks ◽  
M. A. Lane
Keyword(s):  
Surface Finish ◽  
Cell Walls ◽  
Surface Structures ◽  
Efficient Technique ◽  
Low Density ◽  
Polystyrene Foam ◽  
Planar Surfaces ◽  
Machining Characteristics

Diamond-point turning is an efficient technique for machining low-density polystyrene foam, and the surface finish can be substantially improved by grinding. However, both diamond-point turning and grinding tend to tear and fracture cell walls and leave asperities formed by agglomerations of fragmented cell walls. Vibratoming is proving to be an excellent technique to form planar surfaces in polystyrene, and the machining characteristics of vibratoming and diamond-point turning are compared.Our work has demonstrated that proper evaluation of surface structures in low density polystyrene foam requires stereoscopic examinations; tilts of + and − 3 1/2 degrees were used for the stereo pairs. Coating does not seriously distort low-density polystyrene foam. Therefore, the specimens were gold-palladium coated and examined in a Hitachi S-800 FESEM at 5 kV.

Effectiveness of complex inoculation of spring wheat with N[2] -fi xing bacteria Azospirillum brasilense and mold-antagonist Chaetomium cochliodes

2014 ◽  
Vol 1 (3) ◽  
pp. 57-61
Author(s):  
E. Kopylov
Keyword(s):  
Spring Wheat ◽  
Root Zone ◽  
Wheat Root ◽  
Root Surface ◽  
Atmospheric Nitrogen ◽  
Rhizospheric Soil ◽  
Chain Reaction ◽  
Wheat Roots ◽  
Chlorophyll A And B ◽  
Polymerase Chain

Aim. To study the specifi cities of complex inoculation of spring wheat roots with the bacteria of Azospirillum genus and Chaetomium cochliodes Palliser 3250, and the isolation of bacteria of Azospirillum genus, capable of fi xing atmospheric nitrogen, from the rhizospheric soil, washed-off roots and histoshere. Materials and meth- ods. The phenotypic features of the selected bacteria were identifi ed according to Bergi key. The molecular the polymerase chain reaction and genetic analysis was used for the identifi cation the bacteria. Results. It has been demonstrated that during the introduction into the root system of spring wheat the strain of A. brasilensе 102 actively colonizes rhizospheric soil, root surface and is capable of penetrating into the inner plant tissues. Conclusions. The soil ascomucete of C. cochliodes 3250 promotes better settling down of Azospirillum cells in spring wheat root zone, especially in plant histosphere which induces the increase in the content of chlorophyll a and b in the leaves and yield of the crop.

scholarly journals FlsnRNA-seq: protoplasting-free full-length single-nucleus RNA profiling in plants

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Yanping Long ◽  
Zhijian Liu ◽  
Jinbu Jia ◽  
Weipeng Mo ◽  
Liang Fang ◽  
...  
Keyword(s):  
Single Cell ◽  
Cell Walls ◽  
Large Scale ◽  
Full Length ◽  
Cell Level ◽  
Root Cells ◽  
Rna Profiling ◽  
Different Types ◽  
Long Read ◽  
Single Nucleus

AbstractThe broad application of single-cell RNA profiling in plants has been hindered by the prerequisite of protoplasting that requires digesting the cell walls from different types of plant tissues. Here, we present a protoplasting-free approach, flsnRNA-seq, for large-scale full-length RNA profiling at a single-nucleus level in plants using isolated nuclei. Combined with 10x Genomics and Nanopore long-read sequencing, we validate the robustness of this approach in Arabidopsis root cells and the developing endosperm. Sequencing results demonstrate that it allows for uncovering alternative splicing and polyadenylation-related RNA isoform information at the single-cell level, which facilitates characterizing cell identities.

Alterations in cell walls of winter wheat roots during low temperature acclimation

1998 ◽  
Vol 152 (4-5) ◽  
pp. 473-479 ◽  
Author(s):  
Alexey I. Zabotin ◽  
Tatyana S. Barisheva ◽  
Olga A. Zabotina ◽  
Irina A. Larskaya ◽  
Vera V. Lozovaya ◽  
...  
Keyword(s):  
Low Temperature ◽  
Winter Wheat ◽  
Cell Walls ◽  
Temperature Acclimation ◽  
Wheat Roots

The Use of Edible Plants for Rhizofiltration under Different Hydroponic Conditions

2021 ◽  
Author(s):  
juyeon Lee ◽  
minjune Yang
Keyword(s):  
Raphanus Sativus ◽  
Brassica Campestris ◽  
Solid Phase ◽  
Root Surface ◽  
Edible Plants ◽  
Groundwater Samples ◽  
Ph Conditions ◽  
Uranium Accumulation ◽  
High Concentrations ◽  
Hydroponic Conditions

<p>This study conducted a rhizofiltration experiment for uranium-removal with the edible plants (<em>Lactuca sativa, Brassica campestris </em>L., <em>Raphanus sativus </em>L., and <em>Oenanthe javanica</em>) which generally consumed in South Korea. Various batch experiments were performed with different initial uranium concentrations, pH conditions, and genuine groundwater. The results showed the uranium accumulation and bioconcentration factor (BCF) of plant roots increase with an increase in initial uranium concentrations in the solution. Of the four plants, the amount of uranium accumulated in <em>Raphanus sativus </em>L. roots was 1215.8 μg/g DW with the maximum BCF value of 2692.7. The BCF value based on various pH conditions (pHs 3, 5, 7 and 9) of artificial solutions was highest at pH 3 for all four plants, and the BCF value of <em>Brassica campestris </em>L. was the maximum of 11580.3 at pH 3. As a result of rhizofiltration experiments with genuine groundwater contaminated with uranium, the BCF values of <em>Raphanus sativus </em>L. were 1684.7 and 1700.1, the highest among the four species, in Oesam-dong and Bugokdong groundwater samples with uranium concentration of 83 and 173 μg/L. From SEM/EDS analysis, it was confirmed that uranium in contaminated groundwater was adsorbed as a solid phase on the root surface. These results demonstrate that <em>Raphanus sativus </em>L. not only has a high tolerance to high concentrations of uranium and low pH conditions but also has a remarkable potential for uranium accumulation capacity.</p>

scholarly journals THE STRUCTURE OF SOME CYTOPLASMIC COMPONENTS OF PLANT CELLS IN RELATION TO THE BIOCHEMICAL PROPERTIES OF ISOLATED PARTICLES

1957 ◽  
Vol 3 (1) ◽  
pp. 61-70 ◽  
Author(s):  
A. J. Hodge ◽  
E. M. Martin ◽  
R. K. Morton
Keyword(s):  
Endoplasmic Reticulum ◽  
Wheat Root ◽  
Dense Material ◽  
Animal Cells ◽  
Wheat Roots ◽  
Root Cells ◽  
Intact Cells ◽  
Thin Sections ◽  
Isolated Mitochondria ◽  
Silver Beet

1. Electron micrographs of thin sections of material fixed with buffered osmium tetroxide have been used for comparison of the fine structure of isolated cytoplasmic particles from silver beet petioles and roots of germinating wheat with that of the cytoplasm of the intact cells. 2. Mitochondria of wheat roots have an external double membrane and poorly oriented internal double membranes. As compared with the structures seen in situ, the isolated mitochondria showed evidence of some disorganisation of the fine internal structure, probably due to osmotic effects. The possible influence of such changes on the enzymic properties of the isolated mitochondria is discussed. 3. The isolated plant microsomes are mainly spherical vesicular structures consisting of (a) an outer membrane enclosing (b) either an homogeneous slightly dense material (wheat root microsomes) or some granular dense material (silver beet microsomes) and (c) small dense particles, mostly associated with the vesicle membranes. 4. The cytoplasm of the wheat root cells does not contain any structures similar to the isolated microsomes but has a very dense reticular network, consisting of membranes with associated small dense particles, here called the endoplasmic reticulum. The observations indicate that the isolated microsomes arise mainly by rupture and transformation of the membranes of this structure. The effects of such extensive changes in the lipoprotein membranes on the enzymic activities of the endoplasmic reticulum, as studied in isolated microsomes, is discussed. 5. Meristematic wheat root cells contain structures which consist of smooth membranes with associated vacuoles and are similar to the Golgi zones of animal cells. The membranes of these zones probably contribute to the microsomal fraction under the conditions of preparation used for the enzymic and chemical studies previously reported.

Rhythmic patterns of nutrient acquisition by wheat roots

2002 ◽  
Vol 29 (5) ◽  
pp. 595 ◽  
Author(s):  
Sergey Shabala ◽  
Andrew Knowles
Keyword(s):  
Root Zone ◽  
Root Hairs ◽  
Rhythmic Activity ◽  
Root Apex ◽  
Root Surface ◽  
Ion Flux ◽  
Nutrient Acquisition ◽  
Wheat Roots ◽  
Non Invasive ◽  
Functional Zone

Oscillatory patterns in H+, K+, Ca2+ and Cl- uptake were observed at different regions of the root surface, including root hairs, using a non-invasive ion flux measuring technique (the MIFE™ technique). To our knowledge, this is the first report of ultradian oscillations in nutrient acquisition in the mature root zone. Oscillations of the largest magnitude were usually measured in the elongation region, 2–4 mm from the root apex. There were usually at least two oscillatory components present for each ion measured: fast, with periods of several minutes; and slow, with periods of 50–80 min. Even within the same functional zone, the periods of ion flux oscillations were significantly different, suggesting that they are driven by some internal mechanisms located in each cell rather than originating from one ‘central clock pacemaker’. There were also significant changes in the oscillatory characteristics (both periods and amplitudes) of fluxes from a single small cluster of cells over time. Analysis of phase shifts between oscillations in different ions suggested that rhythmic activity of a plasma membrane H+-pump may be central to observed rhythmic nutrient acquisition by plant roots. We discuss the possible adaptive significance of such an oscillatory strategy for root nutrient acquisition.

Distribution of Autofluorescence and Esterase and Peroxidase Activities in the Epidermis of Wheat Roots

1979 ◽  
Vol 6 (2) ◽  
pp. 201 ◽  
Author(s):  
MM Smith ◽  
TP O'brien
Keyword(s):  
Cell Walls ◽  
Outer Wall ◽  
Wheat Root ◽  
Root Cell ◽  
Gaeumannomyces Graminis ◽  
Wall Material ◽  
Wheat Roots ◽  
Pig Liver Esterase ◽  
Auto Fluorescence ◽  
Root Cell Walls

In the wheat root, peroxidases and esterases specific for a-naphthyl esters of acetate, propionate and butyrate are concentrated in cell walls, particularly the outer wall of epidermal cells undergoing extension. In contrast esterases specific for β-naphthyl esters of propionate and butyrate were intra- cellular and concentrated in epidermal and outer root-cap cells of the wheat root. Both α-naphthyl and β-naphthyl esters of longer-chain fatty acids proved to be poor substrates. The esterases and peroxidases associated with the outer epidermal wall may well be involved in turnover of phenolic acids cross-linked to polysaccharides. In this regard, ferulic acid and diferulate were shown to be constituents of wheat-root cell walls. The distribution of these substances can also be inferred from autofluorescence. Treatment with a commercial pig-liver esterase was without effect on the auto- fluorescence of the root cell-walls. Culture filtrates from Gaeumannomyces graminis did remove significant amounts of autofluorescent wall material. These preparations contained α-naphthyl acetate esterase as well as many polysaccharide hydrolase activities.

scholarly journals Modifications of the acyl-d-alanyl-d-alanine terminus affecting complex-formation with vancomycin

1971 ◽  
Vol 123 (5) ◽  
pp. 789-803 ◽  
Author(s):  
M. Nieto ◽  
H. R. Perkins
Keyword(s):  
Complex Formation ◽  
Cell Walls ◽  
Solid Phase ◽  
Side Chain ◽  
Stable Complex ◽  
Cross Link ◽  
Methyl Group ◽  
The Third ◽  
Carboxyl Terminal ◽  
Better Than

Vancomycin forms complexes with peptides terminating in d-alanyl-d-alanine that are analogous to the biosynthetic precursors of bacterial mucopeptides. The specificity of complex-formation has been studied by means of many synthetic peptides, prepared by both solid-phase and conventional methods. The following conclusions can be drawn: (a) three amide linkages are required to form a stable complex; (b) the terminal carboxyl group must be free; (c) the carboxyl terminal and subterminal residues must be either glycine or of the d-configuration; (d) the size of the side chain in these residues greatly influences the affinity for vancomycin, a methyl group being the optimum in each case; (e) the nature of the side chain in the third and fourth residues has a smaller effect on complex-formation, but an l-configuration was somewhat better than a d-configuration in the third position. In addition to acyl-d-alanyl-d-alanine, other peptides that occur in bacterial cell walls will combine with vancomycin, although less strongly, e.g. acyl-d-alanyl-d-α-amino acid (where the terminal d-residue may form the cross-link in mucopeptide structure) and acyl-l-alanyl-d-glutamylglycine (a sequence found in the mucopeptide of Micrococcus lysodeikticus and related organisms). These results throw some light on the specificity of the uptake of vancomycin by living bacteria.

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