THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: XI. THE EFFECT OF STEM RUST ON THE PHOSPHATE FRACTIONS IN WHEAT LEAVES

1962 ◽  
Vol 40 (7) ◽  
pp. 975-985 ◽  
Author(s):  
K. L. Mukherjee1 ◽  
Michael Shaw
Keyword(s):  
Nutritional Status ◽  
Oxidative Phosphorylation ◽  
Organic Phosphate ◽  
Puccinia Graminis ◽  
Organic P ◽  
Fresh Weight ◽  
Uncoupling Of Oxidative Phosphorylation ◽  
Wheat Leaves ◽  
Host Parasite ◽  
Total P

Inorganic, organic, and various organic phosphate fractions were determined in uninfected and infected first seedling leaves of Little Club wheat at various stages between 6 to 18 days after incubation with Puccinia graminis tritici Erikss. and Henn. (Race 15B). Inorganic (Pi), organic (Po), and total P per unit fresh weight increased as uninfected leaves aged and the levels of Pi were much more readily altered by changes in nutritional status and environmental conditions than the levels of Po. Infection increased total P and the highest concentrations occurred at the loci of rust pustules. Since the concentration of P was lower in uninfected portions of infected leaves than in comparable parts of uninfected leaves or in rust pustules, it appeared that P was transported into the pustules from uninfected parts of the leaf. Both Pi and Po were increased by infection, but the Pi/Po ratio was lowered. Acid-soluble bound P, easily hydrolyzable P, lipid P, RNA-P, and residual organic P were all increased by infection.When leaf pieces were infiltrated with and then floated on 10−4 M 2,4-dinitrophenol for 24 hours, the levels of all organic phosphate fractions were lowered and Pi was increased, both in uninfected and infected leaves. Dinitrophenol raised the Pi/Po ratio about 30% in uninfected and about 100% in infected leaves.The results militate against the view that the increase in respiration rate caused by infection is due to the uncoupling of oxidative phosphorylation.

THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: XVIII. DISTRIBUTION OF TRITIUM-LABELLED CYTIDINE, URIDINE, AND LEUCINE IN WHEAT LEAVES INFECTED WITH THE STEM RUST FUNGUS

1967 ◽  
Vol 45 (5) ◽  
pp. 555-563 ◽  
Author(s):  
P. K. Bhattacharya ◽  
Michael Shaw
Keyword(s):  
Stem Rust ◽  
Rust Fungus ◽  
Host Cells ◽  
Fungal Mycelium ◽  
Puccinia Graminis ◽  
Mesophyll Cells ◽  
Wheat Leaves ◽  
Host Parasite

Wheat leaves were detached 6 days after inoculation with the stem rust fungus (Puccinia graminis var. tritici Erikss. and Henn.) and fed with tritiated leucine, cytidine, uridine, or thymidine. Mesophyll cells in infected zones incorporated more leucine into protein and more cytidine and uridine into RNA than did cells in adjacent uninfected tissue. Leucine, cytidine, and uridine were also heavily incorporated by fungal mycelium and developing uredospores. Grain counts over host nuclei in the infected zone were two to three-fold of those over nuclei in adjacent uninfected zones. There was no detectable incorporation of thymidinemethyl-3H into either the fungus or the host cells. The results are discussed.

THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: VIII. EFFECTS OF RUST INFECTION ON ASCORBIC ACID ANDGLUTATHIONE IN WHEAT LEAVES

1961 ◽  
Vol 39 (6) ◽  
pp. 1327-1336 ◽  
Author(s):  
B. I. Sahai ◽  
Michael Shaw
Keyword(s):  
Ascorbic Acid ◽  
Puccinia Graminis ◽  
Oxidized Glutathione ◽  
Redox Potentials ◽  
Rust Infection ◽  
Puccinia Graminis Tritici ◽  
Auxin Content ◽  
Wheat Leaves ◽  
Host Parasite

First seedling leaves of Little Club (susceptible), Khapli I (moderately susceptible), and Khapli (resistant) wheats were inoculated with Puccinia graminis tritici Erikss. and Henn. (Race 15B). Ascorbic (AA) and dehydroascorbic (DHA) acids and glutathione (GSH) were measured at 1–2 day intervals after inoculation until after sporulation. After infection, AA and DHA increased in Little Club and decreased in Khapli. In Khapli the DHA/AA ratio rose sharply 6–8 days after inoculation; in Little Club a similar rise occurred 15–16 days after inoculation. In Khapli I and Little Club, but not in Khapli, GSH increased sharply when sporulation occurred. AA was not detected in uredospores, but DHA was. Oxidized glutathione was not detected in healthy or infected leaves but was present in uredospores. The results are discussed briefly in relation to the changes in auxin content and redox potentials caused by rust infection.

THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: XIV. THE EFFECT OF RUST INFECTION ON THE NUCLEIC ACID CONTENT OF WHEAT LEAVES

1964 ◽  
Vol 42 (11) ◽  
pp. 1531-1540 ◽  
Author(s):  
W. A. Quick ◽  
Michael Shaw
Keyword(s):  
Dry Weight ◽  
Weight Basis ◽  
Nucleic Acid Content ◽  
Fresh Weight ◽  
Fresh Weight Basis ◽  
Rust Infection ◽  
Dna And Rna ◽  
Fungal Dna ◽  
Wheat Leaves ◽  
Host Parasite

The increase in respiration in rust-infected leaves of Little Club wheat was followed and paralleled by an increase in RNA per gram dry weight. The massive increase in dry weight of infected leaves in the later stages of rust development (9–12 days after inoculation) sometimes obscured the increase in RNA when RNA was expressed on a dry weight but not when it was expressed on a fresh weight basis. There was no increase in RNA in rust-infected Khapli. Rust infection had no effect on DNA per gram dry weight in Little Club or Khapli, but DNA per gram fresh weight increased slightly (15%) in Little Club, indicating the synthesis of fungal DNA. Infection had little effect on the protein content of Little Club but markedly lowered that of Khapli. The results are discussed in relation to earlier cytochemical determinations of DNA and RNA in infected tissue.

THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: XIII. THE EFFECT OF STEM RUST ON PURINES IN WHEAT LEAVES

1964 ◽  
Vol 42 (2) ◽  
pp. 139-144 ◽  
Author(s):  
Michael Shaw ◽  
B. I. Sahai Srivastava
Keyword(s):  
Copper Oxide ◽  
Perchloric Acid ◽  
Stem Rust ◽  
Puccinia Graminis ◽  
Puccinia Graminis Tritici ◽  
Detached Leaves ◽  
Wheat Leaves ◽  
Host Parasite

The purines were precipitated from alcohol extracts of Little Club wheat with copper oxide or absorbed from perchloric acid extracts with Norit A. Guanine, adenine, and an unidentified purine were isolated from seedlings germinated in darkness and from the tops of young plants grown in the greenhouse. Adenine and the unidentified purine were present in much larger amounts than guanine. The concentrations of adenine and the unidentified purine in the first seedling leaves were increased approximately four- and five-fold by infection with Puccinia graminis tritici Erikss. and Henn. No evidence was obtained for the presence of any purine or purine-like substance in uninfected or infected leaves which would delay senescence in detached leaves as do kinetin, benzimidazole, and purine-like substances present in coconut endosperm.

scholarly journals Genetic variation of seed phosphorus concentration in winter oilseed rape and development of a NIRS calibration

Euphytica ◽  
2021 ◽  
Vol 217 (4) ◽  
Author(s):  
Jakob Eifler ◽  
Jürgen Enno Wick ◽  
Bernd Steingrobe ◽  
Christian Möllers
Keyword(s):  
Genetic Variation ◽  
Field Experiments ◽  
Seed Quality ◽  
Rapeseed Meal ◽  
Quality Analysis ◽  
Phosphorus Concentration ◽  
Genotypic Differences ◽  
Organic P ◽  
P Concentration ◽  
Total P

AbstractPhytic acid is the major organic phosphorus storage compound in rapeseed. Following oil extraction, the defatted meal is used in feed mixtures for livestock. However, monogastric pigs and chickens can only poorly metabolize phytate. Hence, their excrements are rich in phosphorus (P), which when applied as manure may lead to eutrophication of surface waters. The aim of the present study was to analyze the genetic variation for total and organic P concentration (i.e. mainly phytate) in rapeseed and to compare the results with soybean. Two sets of rapeseed material were tested in field experiments in different environments with varying soil P levels and harvested seeds were used for seed quality analysis. Results revealed significant genotypic differences in total seed P concentration, which ranged from 0.47 to 0.94%. Depending on the experiment, the heritability for total P concentration ranged from 52 to 93%. The organic P portion of total P concentration was above 90% for current rapeseed hybrids. In both sets, there was a significant positive correlation between seed protein and P concentration. A NIRS calibration for total P concentration in intact seeds showed in cross validation a standard error of 0.05% and a coefficient of determination of R2 = 0.83. Total P concentration of soybean seeds and meal was between 0.55 and 0.65%, and around 1.1% for rapeseed meal. Rapeseed meal had a twofold higher ratio of total P to nitrogen concentration as compared to soybean which could be considered adverse when the meal is used for feeding livestock.

THE PHYSIOLOGY OF HOST-PARASITE RELATIONS: IX. FURTHER OBSERVATIONS ON THE ACCUMULATION OF RADIOACTIVE SUBSTANCES AT RUST INFECTIONS

1961 ◽  
Vol 39 (6) ◽  
pp. 1393-1407 ◽  
Author(s):  
Michael Shaw
Keyword(s):  
Specific Activity ◽  
Dry Weight ◽  
Insoluble Fraction ◽  
Pentose Phosphate ◽  
Accumulation Ratio ◽  
X Ray ◽  
Specific Activities ◽  
Leaf Segments ◽  
Wheat Leaves ◽  
Host Parasite

Wang (Can. J. Botany, 38, 635–642 (1960)) concluded that the accumulation of radioactivity observed on radioautographs at infection sites on rusted leaves fed with C14-labelled substances was 'apparent' rather than real. The ‘accumulation ratio’ is defined as the ratio of the specific activities (c.p.m./mg dry weight of intact tissue) of rust-infected to uninfected areas of infected leaves. Theoretical considerations relating to the radioautography of leaves labelled with C14 and to the measurement of ‘accumulation ratios’ by extraction of C14-labelled substances from rusted and uninfected segments of infected leaves, as well as experimental data, show that Wang's conclusion is not generally applicable.Experimentally, it was shown using polymethacrylate C14 sources that differences in distance between sources and X-ray film of the order of 100 μ had no effect on the intensity of autoradiographs. Rust-infected leaves, fed with radioactive glucose, were radiographed between X-ray plates. Localization of radioactivity at infection sites was observed on both ‘dorsal’ and ‘ventral’ radiographs, indicating a real accumulation per unit area. Ventral were more radioactive than dorsal surfaces. The main development of the fungus occurred on the former. Radioautography revealed that C14 from glucose-1-C14, glucose-6-C14, and uniformly labelled glucose fed to excised wheat leaves became localized at 10-day-old rust infections in 2 hours. ‘Accumulation ratios’ calculated from the specific activity of leaf segments remained close to 1.0 for at least 6 hours after introduction of the tracer, but increased to more than 2 after 24 hours. When ‘accumulation ratios’ were calculated from the specific activities of individual pustules (excised with a punch 1 mm in diameter) and interpustular disks, values greater than 1 were observed in 2 hours, thus confirming the results of autoradiography. Differences between the ‘accumulation ratios’ observed with glucose-6-C14 and glucose-1-C14 were consistent with an increased role of the pentose phosphate pathway at infection sites. Incorporation of C14 from uniformly labelled glucose into the alcohol-insoluble fraction of rusted leaf segments was 2.5-fold that in uninfected segments in 6 hours and 3.65-fold in 24 hours. The humin formed during hydrochloric acid hydrolysis accounted for approximately 50% of the activity of the alcohol-insoluble material. The ‘accumulation ratio’ for the alcohol-soluble material was only 1.56 after 24 hours.All the results support the view (Shaw and Samborski, Can. J. Botany, 34, 389–405 (1956)) that there is a quantitative, metabolically dependent accumulation of C14 from radioactive glucose at vigorous rust infections. The relative roles of fungus and host in this process are discussed briefly.

Role of the Ca2+ cycle in uncoupling of oxidative phosphorylation in liver mitochondria of cold-acclimated rats

1985 ◽  
Vol 82 (3) ◽  
pp. 545-547
Author(s):  
Nicolay N. Brustovetsky ◽  
Evgeni I. Maevsky ◽  
Stella G. Kolaeva ◽  
Lubov S. Danilova ◽  
Nikita G. Solomonov
Keyword(s):  
Oxidative Phosphorylation ◽  
Liver Mitochondria ◽  
Uncoupling Of Oxidative Phosphorylation

Effect of Rust Infection on Oxidative Phosphorylation of Wheat Leaves

Nature ◽  
1958 ◽  
Vol 182 (4650) ◽  
pp. 1686-1687 ◽  
Author(s):  
B. I. POZSÁR ◽  
Z. KIRÁLY
Keyword(s):  
Oxidative Phosphorylation ◽  
Rust Infection ◽  
Wheat Leaves
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