THE PEACH REPLANT PROBLEM IN ONTARIO: II TOXIC SUBSTANCES FROM MICROBIAL DECOMPOSITION PRODUCTS OF PEACH ROOT RESIDUES

1955 ◽  
Vol 33 (5) ◽  
pp. 461-486 ◽  
Author(s):  
Z. A. Patrick
Keyword(s):  
Degradation Products ◽  
Sour Cherry ◽  
Toxic Substances ◽  
Root Tips ◽  
Microbial Decomposition ◽  
Meristematic Cells ◽  
Highly Active ◽  
Replant Problem ◽  
Orchard Soils ◽  
Peach Orchard

Experiments were carried out to evaluate the importance of soil toxins in the peach replant problem and to determine whether the substances produced by the interaction of microorganisms occurring in old peach orchard soils and peach root residues were toxic to living peach roots. A rapid and accurate indication as to whether or not these substances were toxic was obtained by determining their effect on the respiration of excised peach root tips. It was demonstrated that substances which inhibit the respiration of excised peach root tips are produced when peach root residues, and also, chemically pure amygdalin, are acted on by certain microorganisms occurring in old peach orchard soils. Such substances were not produced when the soils were autoclaved before amygdalin was added or when other soils were used in which no breakdown of amygdalin had occurred. Again no such inhibiting substances were produced when other root residues, such as sour cherry, tobacco, or pepper roots, were added to these soils in place of peach root residues or amygdalin. The inhibiting substances were readily obtained by extraction with water and they proved to be highly active physiologic agents; the inhibiting effect on the respiration of peach root tips, which ranged from 40 to 90%, could be detected after tips had been less than half an hour in the toxic leachates. In addition to inhibiting respiration these substances also induced darkening and finally the necrosis of meristematic cells. All of these effects proved to be irreversible after tips had been five hours in the toxic leachates. The root tips were apparently killed after this time. Parallel experiments were carried out also with pure amygdalin, and similar inhibition of respiration and injurious effects on meristematic cells were obtained with microbial degradation products of either amygdalin or peach root residues. Water solutions of amygdalin, emulsin, amygdalin and emulsin combined, and various benzaldehyde dilutions were also tested. Inhibition of respiration and darkening of apical meristems were only obtained, however, in solutions where amygdalin was hydrolyzed by emulsin and in the various concentrations of benzaldehyde in water. They were not obtained in the separate solutions of either the glycoside or the enzyme. It was concluded, therefore, that microbial action on the amygdalin fraction of peach roots is mainly responsible for the toxic factor frequently encountered in old peach orchard soils.

The preprophase band: possible involvement in the formation of the cell wall

1976 ◽  
Vol 22 (2) ◽  
pp. 403-411 ◽  
Author(s):  
M.J. Packard ◽  
S.M. Stack
Keyword(s):  
Cell Wall ◽  
Allium Cepa ◽  
Cell Walls ◽  
Preprophase Band ◽  
Adjacent Cell ◽  
Root Tips ◽  
Meristematic Cells ◽  
Narrow Region ◽  
The Matrix

Numerous vesicles were observed among the microtubules of the “preprophase” band in prophase cells from root tips of Allium cepa. The content of these vesicles looks similar to the matrix of adjacent cell walls, and these vesicles often appear to be involved in exocytosis. In addition, the cell walls perpendicular to the plane of (beneath) the preprophase band are often differentially thickened compared to the walls lying parallel to the plane of the band. Our interpretation of these observations is that the preprophase band may direct or channel vesicles containing precursors of the cell wall to localized regions of wall synthesis. The incorporation of constituents of the cell wall into a narrow region defined by the position of the preprophase band may be a mechanism that ensures unidirecitonal growth of meristematic cells.

scholarly journals THE CYTOCHEMICAL LOCALIZATION OF ASCORBIC ACID IN ROOT TIP CELLS

1956 ◽  
Vol 2 (1) ◽  
pp. 87-92 ◽  
Author(s):  
William A. Jensen ◽  
Leroy G. Kavaljian
Keyword(s):  
Ascorbic Acid ◽  
Cell Surface ◽  
Silver Nitrate ◽  
Ribonucleic Acid ◽  
Root Tip ◽  
Root Tips ◽  
Cytochemical Localization ◽  
Meristematic Cells ◽  
Tip Cells ◽  
Root Tip Cells

The intracellular distribution of ascorbic acid was studied in frozen-dried root tips of Allium cepa and Vicia faba by the silver nitrate procedure. The sites of the ascorbic acid as indicated by the deposited silver appear as spherical (0.2 to 0.6 µ in diameter) cytoplasmic particles. The site appears to have small amounts of lipides and to be rich in ribonucleic acid. These particles are concluded to be submicroscopic in size and associated, in the elongating cell, with the cell surface. In the meristematic cells they appear fewer in number and are distributed throughout the cytoplasm.

scholarly journals Influence of extract from shoots of Taxus baccata var. elegantissima on ultrastructure and tubulin cytoskeleton of meristematic cells of Allium cepa L. roots

2014 ◽  
Vol 71 (3) ◽  
pp. 211-221 ◽  
Author(s):  
Agnieszka Majewska ◽  
Mirosława Furmanowa ◽  
Kazimierz Głowniak ◽  
Joanna Guzewska ◽  
Alicja Zobel ◽  
...  
Keyword(s):  
Allium Cepa ◽  
Chromatin Condensation ◽  
Preprophase Band ◽  
Taxus Baccata ◽  
Cell Nuclei ◽  
Root Tips ◽  
Meristematic Cells ◽  
Allium Cepa L ◽  
Interphase Cells ◽  
Average Size

We investigated the influence of extract from <em>Taxus baccata</em> var. Elegantissima (TbE) shoots in 1:8 dilution, containing paclitaxel in concentration of 81,6 µg/g fresh mass on ultrastructure and tubulin cytoskeleton of meristematic cells of <em>Allium cepa</em> L. root tips. Incubation time 3, 6, 12 and 24 h was followed with postincubation in water for 12 and 24 h. During shorter incubation (till 12 h) the surface of the cell nuclei decreased and chromatin became condensed (in comparison to control) but after 24 h the average surface increased and chromatin condensation decreased. In the course of incubation the average size of plastids and vacuoles increased. Moreover, after treatment mitochondria and plastids showed degradation of ultrastructure, which was reversed after 12 h of postincubation. Immunocytochemical assays demonstrated that in the course of incubation in the ThE extract, the tubulin cytoskeleton became partially disorganised. In most interphase cells, cortical microtubules (MTs) lost their oval transverse orientation. The preprophase band (PPB) position in the cell was often asymmetrical. The MTs array of the karyokinetic spindle and phragmoplast was also disturbed. These alterations were completely reversed during postincubation.

scholarly journals The Role of Arabinogalactan Type II Degradation in Plant-Microbe Interactions

2021 ◽  
Vol 12 ◽  
Author(s):  
Maria Guadalupe Villa-Rivera ◽  
Horacio Cano-Camacho ◽  
Everardo López-Romero ◽  
María Guadalupe Zavala-Páramo
Keyword(s):  
Cell Wall ◽  
Plant Defense ◽  
Plant Cell ◽  
Plant Cell Wall ◽  
Degradation Products ◽  
Hydrolytic Enzymes ◽  
Pathogenic Fungi ◽  
Plant Interactions ◽  
Root Tips ◽  
Microbe Interactions

Arabinogalactans (AGs) are structural polysaccharides of the plant cell wall. A small proportion of the AGs are associated with hemicellulose and pectin. Furthermore, AGs are associated with proteins forming the so-called arabinogalactan proteins (AGPs), which can be found in the plant cell wall or attached through a glycosylphosphatidylinositol (GPI) anchor to the plasma membrane. AGPs are a family of highly glycosylated proteins grouped with cell wall proteins rich in hydroxyproline. These glycoproteins have important and diverse functions in plants, such as growth, cellular differentiation, signaling, and microbe-plant interactions, and several reports suggest that carbohydrate components are crucial for AGP functions. In beneficial plant-microbe interactions, AGPs attract symbiotic species of fungi or bacteria, promote the development of infectious structures and the colonization of root tips, and furthermore, these interactions can activate plant defense mechanisms. On the other hand, plants secrete and accumulate AGPs at infection sites, creating cross-links with pectin. As part of the plant cell wall degradation machinery, beneficial and pathogenic fungi and bacteria can produce the enzymes necessary for the complete depolymerization of AGs including endo-β-(1,3), β-(1,4) and β-(1,6)-galactanases, β-(1,3/1,6) galactanases, α-L-arabinofuranosidases, β-L-arabinopyranosidases, and β-D-glucuronidases. These hydrolytic enzymes are secreted during plant-pathogen interactions and could have implications for the function of AGPs. It has been proposed that AGPs could prevent infection by pathogenic microorganisms because their degradation products generated by hydrolytic enzymes of pathogens function as damage-associated molecular patterns (DAMPs) eliciting the plant defense response. In this review, we describe the structure and function of AGs and AGPs as components of the plant cell wall. Additionally, we describe the set of enzymes secreted by microorganisms to degrade AGs from AGPs and its possible implication for plant-microbe interactions.

scholarly journals THYMIDINE DEGRADATION PRODUCTS IN PLANT TISSUES LABELED WITH TRITIATED THYMIDINE

1963 ◽  
Vol 17 (1) ◽  
pp. 59-66 ◽  
Author(s):  
S. T. Takats ◽  
R. M. S. Smellie
Keyword(s):  
Acetic Acid ◽  
Metabolic Pathways ◽  
Time Course ◽  
Degradation Products ◽  
Tritiated Thymidine ◽  
Lilium Longiflorum ◽  
Plant Tissues ◽  
Root Tips ◽  
Radioactivity Analysis ◽  
Ethanol Acetic Acid

A study of the metabolic pathways of H3-thymidine utilization in buds of Lilium longiflorum and root tips of Vicia faba was undertaken in order to obtain information that might explain the binding of H3 from H3-thymidine in the cytoplasm of these plants. H3-thymidine was administered for various periods of time, the tissues were fixed and processed in the manner routinely used in preparation for sectioning and autoradiography, and the radioactivity removed in this way from the tissues was determined. It was found that the ethanol/acetic acid fixative contained the major portion of the radioactivity. Analysis of this extract by paper chromatography showed that the radioactivity was distributed among various degradation products of thymidine, principally ß-ureidoisobutyric acid and ß-aminoisobutyric acid. Time course experiments with Vicia showed that these degradation products rapidly appeared in the tissue during incubation with H3-thymidine, while H3-thymine appeared in the incubation medium. Preliminary studies indicated that Vicia root tips incubated with H3-dihydrothymine for 24 hours would bind a small amount of H3 non-specifically in the cells. It seems unlikely that utilization of degradation products of H3-thymidine is sufficient to explain labeling which is concentrated in the cytoplasm.

scholarly journals Monoclonal antibody to intermediate filament antigen cross-reacts with higher plant cells.

1985 ◽  
Vol 100 (5) ◽  
pp. 1793-1798 ◽  
Author(s):  
P J Dawson ◽  
J S Hulme ◽  
C W Lloyd
Keyword(s):  
Monoclonal Antibody ◽  
Intermediate Filament ◽  
Higher Plants ◽  
Plant Cells ◽  
Heterologous Proteins ◽  
Root Tips ◽  
Suspension Cells ◽  
Higher Plant ◽  
Meristematic Cells ◽  
Carrot Protoplasts

The monoclonal antibody (anti-IFA) raised (Pruss et al., 1981, Cell 27:419-428) against an intermediate filament antigen, which is widespread throughout phylogeny, has been shown here to cross-react with higher plants. On immunoblotting, anti-IFA cross-reacted with proteins in homogenates of carrot suspension cells and of meristematic cells from onion root tips. A 50-kD cross-reactive protein was enriched in a fraction that consisted of detergent-insoluble bundles of 7-nm fibrils from carrot protoplasts (Powell et al., 1982, J. Cell Sci. 56:319-335). By use of indirect immunofluorescence, anti-IFA stained formaldehyde-fixed onion meristematic cells and carrot protoplasts in patterns approximating those obtained with monoclonal anti-tubulins. That anti-IFA was not recognizing plant tubulins was established by use of immunoblots of two-dimensional gels on which the proteins that comprised isolated fibrillar bundles and taxol-purified carrot tubulins had been separated. The two groups of proteins had different positional coordinates: anti-IFA recognized the fibrillar bundle proteins, and anti-tubulins recognized plant microtubule proteins with no cross-reaction to the heterologous proteins. Likewise, formaldehyde-fixed taxol microtubules from carrot cells could be stained with anti-tubulin but not with anti-IFA. It is concluded that an epitope common to intermediate filaments from animals co-distributes with microtubules in higher plant cells.

scholarly journals Influence of hypoxia on protoplast structure in the plant cell

2015 ◽  
Vol 44 (3) ◽  
pp. 369-376
Author(s):  
Maria Podbielkowska ◽  
Bożena Borys
Keyword(s):  
Endoplasmic Reticulum ◽  
Nucleic Acids ◽  
Allium Cepa ◽  
Plant Cell ◽  
Rough Endoplasmic Reticulum ◽  
Sodium Azide ◽  
Root Tips ◽  
Respiratory Inhibitors ◽  
Meristematic Cells ◽  
Parallel Structures

An influence of hypoxia on the protoplast’s structure in the root tips meristematic cells of onion (<i>Allium cepa</i> L.) and of <i>Tradescantia bracteata</i> Small has been investigated. Hypoxia was caused either by respiratory inhibitors (sodium azide, 2,4-dinitrophenol), phosfon-D or by anaeroibic conditions. In both cases characteristic membranization of cytoplasm was observed. It appeared as spherical and parallel structures of rough endoplasmic reticulum. The observed hypertrophy was not connected with the increase of nucleic acids and proteins synthesis. In the examined cells the membranization was accompanied by an increase of the lipids content.

scholarly journals ДІЄТИЧНА ДОБАВКА ІМУНОТРОПНОЇ ДІЇ НА ОСНОВІ ПРОДУКТІВ ДЕСТРУКЦІЇ ПРОБІОТИЧНИХ БАКТЕРІАЛЬНИХ КУЛЬТУР

2018 ◽  
Vol 82 (1) ◽  
Author(s):  
Антоніна Іванівна Капустян ◽  
Наталля Кирилівна Черно
Keyword(s):  
Molecular Weight ◽  
Dietary Supplement ◽  
Bacterial Cell ◽  
Degradation Products ◽  
General Scheme ◽  
Animal Experiments ◽  
Reaction Medium ◽  
Low Molecular Weight ◽  
Toxic Substances ◽  
Absorption Bands

У роботі розглянуто можливість отримання імунотропної дієтичної добавки на основі низькомолекулярних продуктів деградації пептидогліканів клітинних стінок пробіотичних бактерій. Встановлено раціональні режими автолізу біомаси як первинного етапу деструкції пептидогліканів бактеріальних клітинних стінок. Показано, що найбільш інтенсивний лізис клітин відбувається при експозиції культуральної рідини при 90°C протягом 15 хв після 8-ї години культивування, про що свідчить максимальне накопичення амінокислот у реакційному середовищі (1,8 мг/см3). Проведено оптимізацію процесу деструкції пептидогліканів бактеріальних клітин, які піддавали лізису, ферментним препаратом панкреатином. Ефективність ферментолізу визначали за накопиченням імунотропних низькомолекулярних пептидів залежно від концентрації ферменту (СЕ), субстрату (СS) в реакційній суміші та тривалості процесу (τ). Встановлено, що раціональний режим ферментолізу, який забезпечує максимальне накопичення низькомолекулярних пептидів (0,569 мг/см3, досягається за наступних значень факторів: СЕ=12,5 мг/см3, СS=70,0 мг/см3, τ=245,6 хв. Зразок низькомолекулярних пептидів, отриманий за раціональних режимів деструкції, досліджено методом ІЧ-спектроскопії. Встановлено, що у його ІЧ-спектрі присутні смуги поглинання, які відповідають коливанням аміногруп, пептидних зв’язків, піранозної форми глюкози, залишки якої входять до складу мурамової кислоти, та N-ацетилглюкозаміну пептидоглікану. Приведено загальну схему, що ілюструє послідовність процесів виробництва імунотропної дієтичної добавки .У дослідах на щурах встановлено ефективну дозу отриманої дієтичної добавки –0,06 мг/кг маси тіла.  The possibility of obtaining an immunotropic dietary supplement based on low molecular weight degradation products of cell wals peptidoglycans of lactic and bifidobacteria composition has been considered. Rational regimes of autolysis of biomass as the primary stage of degradation of peptidoglycans of bacterial cell walls have been established. It was shown that the most intensive lysis of cells takes place when the culture liquid is treated at a temperature of 90 °C for the 8th hour of cultivation, as indicated by the maximum accumulation of amino acids in the reaction medium (1.8 mg/cm3). Optimization of the destruction process of bacterial cell peptidoglycans exposed to lysis, by enzyme preparation with pancreatin, was carried out by the mathematical planning method of the multifactorial experiment. The effectiveness of enzymatic hydrolysis was determined by the accumulation of immunotropic low molecular weight peptides, depending on the concentration of the enzyme (CE), the substrate (CS) in the reaction mixture and the duration of the process (τ). The rational value of the factors CE, CS and τ that provide the maximum concentration of low molecular weight peptides (0.569 mg/cm3) in the enzymatic hydroltsate are CE=12.5 mg/cm3, Cs=70.0 mg/cm3, τ=245.6 min. A sample of low molecular weight peptides obtained from rational degradation regimes was investigated using the IR spectroscopy method. It has been established that in its spectrum absorption bands corresponding to fluctuations of amino groups, peptide bonds are presentred, which, in fact, take place in the structure of peptides. Fluctuations of the pyranose glucose form, which is included in the muramic acid and N-acetylglucosamine of peptidoglycan, have also been observed. The general scheme of the sequence of production processes of an immunotropic dietary supplement has been given. In animal experiments, it has been established that this additive, in accordance with the classification of chemicals substances to the degree of danger, belongs to class 4 (low-toxic substances). The effective dose of the obtaned dietary supplement is 0.06 mg/kg body weight.

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