bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the Germination of Pine Pollen (Pinus mugo) in vitro. II. Effects of Different Ions
Authors: Nygaard Per 
Published: April 2006

AbstractStudies on the initial germination of pollen of Pinus mugo showed no significant influence of ions on O2 uptake and uptake of 32P‐labelled phosphate. At the onset of tube growth O2 uptake decreased in the absence of calcium. In inorganic media tube growth and 32P uptake were reduced in the absence of calcium or boric acid. In the absence of calcium a requirement for magnesium was observed. When the medium was deprived of polyvalent ions with EDTA, growth and 32P uptake ceased. The presence of calcium in the medium was found to be essential for the maintenance of the structural and functional integrity of the cell membranne. — The ion requirement was more pronounced when tube growth was stimulated with sucrose. Calcium, magnesium, boric acid, and nitrate (as nitrogen source) were essential constitutents of the medium. The stimulation due to calcium required either magnesium or boric acid. — A density effect was observed which can be related to diffusible substances from the pollen into the medium. This was not observed when calcium and magnesium were present in the medium. The phenomenon is explained as an enrichment of the medium with diffusible substances from non‐germinated dead pollen. — Germination and the tube growth were found to be greatly dependent on a short period of equilibration of pollen at room temperature before sowing.
Isoenzyme Patterns in Developing Xanthium Leaves
Authors: Chen Shaio‐Lim , Towill Leslie R. , Loewenberg J. R. 
Published: April 2006

AbstractThe isoenzyme patterns of individual Xanthium leaves at various stages of development were determined by acrylamid electrophoresis. The Leaf Plastochron Index was used to measure leaf and plant age. The nature of the changes occurring during leaf development differed from enzyme to enzyme and from gfrom isoenzyme to isoenzyme; for instance, one of the glucose‐6‐phosphate dehydrogenases was peculiar to very young leaves, another to rapidly expanding leaves, and yet another to still older ones. On the other hand, the number of amylase isoenzymes merely increased with leaf age. Many of the changes in the isoenzyme patterns coincide with the cessation of cell division in the leaf or with the completion of leaf growth. The particular isoenzyme patterns of a given leaf depended on both leaf and plant age. While the isoenzyme patterns of leaves from maximum aldolase activity per unit protein and at a later stage than the leaves from the vegetative plants.
Relationship between Increased NADP‐linked Glyceraldehyde‐3‐phosphate Dehydrogenase Activity and Protein Synthesis during the Greening of Etiolated Pea Seedlings
Authors: Basscarini Assunta , Melandri Bruno A. 
Published: April 2006

AbstractPhotoinduction of NADP‐linked glyceraldehyde‐3‐phosphate dehydrogenase activity in etiolated pea seedlings was investigated in the presence of various concentrations of four inhibitors of protein synthesis (cycloheximide, actinomycin D, chloramphenicol and puromycin) and one photosynthesis inhibitor (DCMU), and compared with increase in chlorophyll and total protein contents. The enzymatic activity and chlorophyll showed similar responses to the action of the antibiotics, whereas they were not significantly affected by the presence of DCMU.
The Effect of Darkness on the Leghemoglobin Content and Amino Acid Levels in the Root Nodules of Pea Plants
Authors: Roponen Ilma 
Published: April 2006

AbstractThe dependence of the nitrogen fixing system in the root nodules of pea plants (Pisum sativum) L. cv. Torsdag II) on light induced reactions was studied. The pots of the inoculated pea plants, after the nolules had fixed nitrogen for a fornight, were transferred to a dark room. The control plants were kept under normal lighting conditions.The decay of leghemoglobin was measured after photosynthesis had ceased. In the dark the red nodules turned green in three days, when about half of the haem had been broken down. The plants in normal lighting conditions had maintained the red nodules. The appearence of leghemoglobin and bacteroids was simultaneouos. In normal lighting conditions the number of bacteroids was about 1.6 × 108 per g fresh nodules. The appearance of leghemoglobin and bacteroids was simultaneous. In normal lighting conditons the number of bacteroids was bout 1.6 × 108 per g fresh nodules. At the same time as the nodules turned green in the dark most of the bacteroids disappeared and the number of rod‐shaped bacteria increased. After five days int the dark thenumber of bacteria of the green nodules was 2.2 × 108 per g fresh nodules. A large increase of of bacteria in the nodules is one of the results after the termination of effective symbiosis.Quantitative estimations were made with an automatic amino acid analysator of the amino acid composition in the root nodules of pea plants grown in the light and of pea plants grown in the dark. Altogether 27 amino acids and amides and 3 unknown ninhydrin positive compounds were found in the free amino acid fraction. In the red N‐fixing nodules asparagine, the amide of aspartic acid, was the most prominent (more than 50 per cent of the total amino acid fraction), indicating the energy charge of the nitrogen fixation. 5 days in the dark affected the proportions of the amino acids as follows. Asparagine, homoserine, γ‐aminobutyric acid and ethanolamine were decreased and the most of the others increased.In the hydrolysate of the non‐soluble protein fraction 25 amino acids could be detected. The proportions of the amino acids in the root nodules of light‐grown and dark‐grown pea plants were very similar. Hydroxyproline and α, γ‐diaminopimelic acid (DAP) were found in these fraction. Most of the DAP was contained in the peptide fraction. Also hydroxyproline was found to a small extent. It was assumed that the amino acids in this fraction were derived from the peptides of both plant cells and rhizobia.
Studies of the Growth in Culture of Excised Wheat Roots
Authors: Woodruffe Patricia , Anthony A. , Street H. E. 
Published: April 2006

AbstractExcised wheat roots in culture release a substance inhibitory to their growth and which can be absorbed on activated charcoal. This growth inhibitor can be isolated in pure form by diethylether extraction followed by DEAE cellulose and thin‐layer chromatography. At very low concentration it inhibits lateral root development. The significance of this inhibitor to the problem of the continuous growth of cultured wheat roots is discussed.
Effect of 3‐Amino‐1,2,4‐Triazole on the Alcohol Soluble Nitrogen Compounds in Cirsium arvense
Authors: Burt G. W. , Muzik T. J. 
Published: April 2006

AbstractChanges in the soluble nitrogen compounds after application of 3‐amino‐1,2,4‐triazole (amitrole) to amitrole susceptible and amitrole resistant ecotypes of Cirsium arvense were investigated. One day after treatment with amitrole the concentration of all nitrogen compounds tested in the leaves of the susceptible ecotype was reduced, but none was eliminated. Five days after treatment the concentration of the same compounds increased in the leaves above the control (0 amitrole) concentration. The resistant ecotype had less change in nitrogen compounds than did the susceptible ecotype. Changes in the soluble nitrogen compounds in the stem and root fraction were less than in the leaf fraction. The authors suggest a two phase reaction of the soluble nitrogen compounds due to amitrole treatment. It is concluded that the primary biochemical lesion of amirole in mature Cirsium arvense is not the elimination of glycine, serine, or any other soluble nitrogen compound.
Growth of Certain Aquatic Omycetes on Amino Acids I. Saprolegnia, Achlya, Leptolegnia, and Dictyuchus
Authors: Gleason Frank H. , Rudolph Catherine R. , Price Jeffrey S. 
Published: April 2006

AbstractFour fungi in the order Saprolegniales —Saprolegnia sp., Achlya ambisexualis, Leptolegnia eccentrica and Dictyuchus sterile– were tested for growth in synthetic media containing one of the following carbon sources: glucose, maltose, sucrose, alanine, proline, glutamate, leucine, arginine and phenylalanine. All of these compounds were effective substrates for one or more of the four fungi. The ability of Saprolegnia sp. to utilize other substrates was studied. Saprolegnia sp. can metabolize soluble starch, fructose, ornithine, aspartate, serine, and lysine but did not grow on galactose and eight additional amino acids.
The Role of Ethylene Diisothiocyanate (EDI) in the Antifungal Action of Disodium Ethylene Bisdithiocarbamate (Nabam). I. The Mode of Action of EDI on the Metabolism of Yeast
Authors: Håbrekke J. I. , Goksøyr J. 
Published: April 2006

AbstractWith glucose as a substrate, the oxygen consumption in yeast in inhibited by 2· 10‐5M ethylene diisothiocyanate. The degree of inhibition was only to a small extent dependant on pH. Radiorespirometric experiments with uniformely labelled glucose showed that the CO2‐production from glucose increased, probably due to increased glycolytic activity. Conversion of C‐1 to CO2 was unaffected by the inhibitor, while the evolution of CO2 from C‐6 was strongly inhibited. The same was the case with CO2 from C‐1 in acetate. Respiration of ethanol was more strongly inhibited than that of glucose or acetate.Experiments with dual wavelength spectrophotometry showed the inhibition to be located on the Krebs cycle side of the respiratory flavoproteins. It is concluded that the action of ethylene diisothiocyanate on respiration must be located at the mitochondria.
Effect of Fluoride on Ribosomes from Corn Roots. Changes with Growth Retardation
Authors: Chang Chong W. 
Published: April 2006

AbstractGrowth inhibition caused by fluoride was further studied by analyzing free and bound ribosomes, and the ribosomal components in corn roots. Ribosomes were isolated by differential centrifugation. Ribosomal components were analyzed by column chromatography and electrophoresis. Fluoride reduces the amounts of both free and bound ribosomes. Fluoride also modifies the RNA to protein ratio of bound ribosomes more than that of free ribosomes. Fluoride does not affect base ratios of the ribosomal RNA, but reduces its content and changes the structure of the ribosomal protein moiety.
Cytokinin‐cytokinin‐Induced tuber formation Tuber Formation on Stolons of Solanum tuberosum
Authors: Smith O. E. , Palmer C. E. 
Published: April 2006

AbstractKinetin‐induced tuberization of isolated stolons was investigated with regard to accumulation of labelled kinetin, starch, protein and nucleic acid synthesis. Using kinetin‐8‐14C, it was found that more labelled meterial appeared at the locus of tyber formation that in other parts of the stolon. Substantial accumulation was evident before visible signs of tuber formation. The basal portion of the stolon also accumulated substantial amounts of labelled material.Kinetin‐treated stolons showed extensive starch accumulation which was not evident in gibberellic acid‐treated or untreated stolons. Starch accumulation occurred before any visible sign of tuber formation. There was no marked differences in the ability of the apical 0.5 cm of kinetin‐treated and untrated stolons to incorporate 14 C uridine into RNA and 14C leucine into TCA precipitable protein. From these results it was concluded that kinetin‐induced tuber formation may not involve the synthesis of new proteins. It is suggested that kinetin may be regulating tuber formation by suppressing starch hydrolase activity and stimulating starch synthetase activity whereas gibberellic acid inhibits tuber formation by promoting starch hydrolase activity or by suppressing starch synthesizing enzymes.
Evidence for Photorespiration in Tropical Grasses
Authors: Irvine Jamesz E. 
Published: April 2006

AbstractSugarcane leaves respired in full light and the CO2 evolved could be detected in sorghum or miaze photosynthesizing in the same closed system. A combination of radiometric and infra‐red gas analysis techniques allowed the estimation of photorespiration (total CO2 evolution in light) and photosynthesis at increasing light intensities and of dark respiration. Rates of CO2 evolution approaching those of temperate zone plants occurred at lower light intensities but rapidly decreased with higher light. Smaller but significant quantities of 14CO2 were released even at intensities approximating full sunlight in leaves of maize, sorghum and sugarcane. Highly efficient CO2 capture may explain the low rates of photorespiration at high light intensities.
Chlorophyll Degradation by Light in Leaf Discs in the Presence of Sugar
Authors: Khudairi A. K. 
Published: April 2006

AbstractLeaf dises of Xanthium pensylvanicum floated on 0.01 M sucrose solutions inside Petri dishes incubated in a growth chamber at 22°G with illiumination of 3000 lux for 16 to 24 hours of light lost 90% of their chlorophyll. Similar dises floated on water under the same conditions lost 60% of their chlorophyll by the end of one week. chlorophyll degradation calculated as percent of the optical density of the original chlorophyll content accelerated with time. A minimum light intensity of 2000 lux is required for such degradation. Higher intensities accelerated chlorophyll degradation. Glucose, ribose, and xylose have effects similar to sucrose on chlorophyll destruction in the presence of light. chlorophyll degradation was found to be temperature sensitive. There is no difference in chlorophyll content in the presence or absence of sucrose at 10 °C.
Effects of Abscisic Acid, Salicylic Acid and Trans‐cinnamic Acid on Phosphate Uptake, ATP‐level and Oxygen Evolution in Scenedesmus
Authors: Tillberg Jan‐Eric 
Published: April 2006

AbstractThe effects of abscisic acid, salicylic acid and trans‐cinnamic acid were tested on the light‐induced phosphorylating reactions and oxygen evolution of the unicellular green alga Scenedesmus.It was found that abscisic acid and cinnamic acid had practically no influence on the total inorganic phosphate uptake, while salicylic acid in the concentration range of 10‐6 to 10‐3M gave a small decrease in the total inorganic phosphate uptake.The ATP level in the cells is in most cases increased when these three acids are given to the algae.The oxygen output is not significantly changed by abscisic acid or salicylic acid. Trans‐ cinnamic acid inhibits the oxygen evolution at concentrations of 10‐4–10‐3MNone of the substances investigated caused such effects on photophosphorylation and oxygen evolution in Scenedesmus as those caused by the inhibitor β‐complex from potatoes according to earlier reports. It is suggested that these effects are due to other components in the inhibitor β‐complex.
Effect of Fatty Acids and Methyl Octanoate on Resting Mycelium of Boletus variegatus
Authors: Pedersen T. A. 
Published: April 2006

AbstractThe endogenous respiration of resting, submerged grown Boletus variegatus mycelium has been determined. In young cultures the intensity of the endogenous oxygen uptake was subject to great variations during the first few hours of starvation. However, by using six to eight days old mycelium the Qo2 values could be kept at a relatively low and constant level for at least nine hours.Inhibition of the endogenous respiration was found after addition of n‐saturated C‐2 to C‐12 fatty acids (2 × 10‐3M, pH 4.85). The inhibitory effect of the compound was dependent on the length of the carbon chain. Maximum effects were obtained for acids with eight to twelve carbon atoms per molecule. The inhibition was also dependent on the amount of undissociated acid present. By raising the pH so that the fatty acid dissociated the established inhibition was partly reversed. The effect of the neutral compound methyl octanoate was in essence identical to that obtained with octanoic acid.After fatty acid addition a close correspondence was found between the degree of inhibition of the oxygen uptake and the amount of UV absorbing substances leaking out from the cells. This extracellular material had an absorption maximum at 260 nm and a minimum around 240 nm. The leaking was ascribed to interaction between fatty acids or methyl octanoate and lipophilic substances of the cytoplasmic membrane. It is suggested that the inhibitory action on the endogenous respiration is due to similar effects on intracellular membrane systems.
Oscillations bioélectriques dans des membranes de Nitella
Authors: Radenoviç ČEdomir , Penčic̀ Milutin 
Published: April 2006

AbstractThe results of synchronous registering of bioelectrical potentials upon some cell phases under definite environemental conditons can be used more universally in studies on the nature of bioelectrical appearances in living plant cells.Determinations were made on different functional dependence of the bioelectrical potential of the outside cell membrane, the bioelectrical potential of cytoplasm and the bioelectrical potential of vacuola under the same environmental conditions. Different properties of the cell structures manifest unequal characteristics in rhytmical fluctuation of bioelectrical potentials; unsynchronous and synchronous rhytmical fluetuations in the bioelectrical potential of cytoplasm and the outside cell membrane might occur. The amplitudes of the cytoplasm biometrical potential and the corresponding amplitude of biometrical potential in the outside cell membrane range up to 70 mV and 15 mV, respectively.
Péétration et migration d'éléments minéraux appliqués sur les feuilles en présence de diméthylsulfoxyde
Authors: Chamel André , Simiand Josette 
Published: April 2006

AbstractThe aim of this work was to determine the effect of DMSO on the uptake and translocation of potassium and phosphorus applied on corn and bean leaves. Radioactive isotopes 42K and 32P were used in most of the experiments. The results obtained reveal that DMSO (0.5% and above) increases the penetration of potassium applied as nitrate or chloride, but seems to have no effect on the penetration of 32P when applied as different phosphates.
The Effect of Gibberellic Acid, when Applied to the Rooting Medium, on Nodulation and Nitrogen Fixation in Gram (Cicer arietinum)
Authors: Swaraj K. , Garg O. P. 
Published: April 2006

AbstractPlants of a pure line variety, G 24, of Cicer arietinum L. were grown in sand culture. After an initial dose of a complete nutrient solution, a nitrogen free nutrient solution was supplied to the sand at intervals and a standard rhizobial culture was added twice. The plants were treated with two concentrations of gibberellic acid (20 mg/I and 100 mg/I) through the rooting medium. At suitable intervals two pots from each treatment were sampled. Observations were made regarding the earliest initiation of nodulation, the number, weight and colour of nodules and the nitrogen content of different plant organs under various treatments.GA3 treatments enhanced nodule initiation. While 20 mg/1 somewhat enhanced nodule number, weight and nitrogen content, 100 mg/I caused detrimental effects in the long run. Pod formation was delayed with GA3, the effect being much more pronounced with the higher concentration used. Pod and seed weights under 20 mg/1 GA3 were almost comparable to the control, but 100 mg/I proved very deleterious.
Effects of 2‐Chloroethylphosphonic Acid and Gibberellic Acid on Sex Expression and Growth of Pumpkins
Authors: Splittstoesser Walter E. 
Published: April 2006

AbstractTreatment of pumpkin plants with 2‐chloroethylphosphonic acid (CEPHA) induced a greater production of female flowers, shorter internodes and earlier fruit set while treatment with gibberellic acid (GA) induced a greater production of male flowers, longer internodes and later fruit set. Although CEPHA induced the production of a greater number of female flowers, the bulk of the flowers aborted and only a slight increase in the number of fruits per pumpkin plant occurred.The addition of equal concentrations of CEPHA and GA resulted in pumpkin plants with longer internodes and a greater number of female flowers than the untreated plants, although GA partially overcame the effect of CEPHA. The mode of action of CEPHA and GA on sex expression is discussed.
Growth of Certain Aquatic Oomycetes on Amino Acids II. Apodachlya, Aphanomyces, and Pythium
Authors: Gleason Frank H. , Stuart Thomas D. , Price Jeffrey S. , Nelbach EdwardT. 
Published: April 2006

AbstractFour aquatic fungi —Apodachlya brachynema and A. minima (Leptomitales), Aphanomyces laevis (Saprolegniales), and Pythium ultimum (Peronosporales) —were tested for growth in synthetic media containing one of a variety of carbon sources. Apodachlya brachynema readily utilized five amino acids — alanine, glutamate, aspartate, proline and leucine — as well as glucose and acetate. Growth on sucrose as a carbon source was slight. Apodachlya minima differed from A. brachynema in that it could not utilize proline and leucine. Aphanomyces laevis grew well on only three of the substrates tested — glucose, alanine and glutamate. Pythium ultimum utilized glucose, sucrose, maltose, cellobiose, alanine, glutamate, aspartate, proline, asparagine, ornithine, and serine, but not eight other amino acids. All of these fungi hydrolyzed gelatin. Radioactively labeled carbon dioxide was released during incubation of Aphanomyces laevis in media containing labeled leucine, proline, or phenylalanine. These data provide evidence of some catabolism of the three substrates although none of these substrates can support the growth of Aphanomyces laevis as a sole source of carbon and nitrogen.
Studies of Auxin Protectors VIII. Evidence that Auxin Protectors Act as Cellular Poisers
Authors: Stonier Tom , Hudek Joseph , Vande‐Stouwe Robert , Yang Hsin‐mei 
Published: April 2006

AbstractAuxin protectors completely inhibit the peroxidase‐catalyzed oxidation of indoleacetic acid (IAA). Presumably only when the protector substance itself has been oxidized, does IAA oxidation begin. Reduced nicotinamide‐adenine dinucleotide (NADH) mimics the native auxin protectors: In the presence of NADH, the peroxidase‐catalyzed oxidation of IAA does not begin until almost all the NADH has been oxidized.Auxin protectors slow the oxidation of NADH in the presence of the peroxidase complex (enzyme plus manganese). However, in the absence of the peroxidase complex, protectors actually accelerate the spontaneous oxidation of NADH. Protectors can also accelerate the oxidation of the dye 2,6‐dichlorophenol‐indophenol, especially in the presence of manganese. Protector oxidized by boiling with traces of hydrogen peroxide will act as an electron acceptor in the peroxidase‐catalyzed oxidation of NADH. The reversible redox role of auxin protectors implies that they can act as cellular poisers.
Interactions between Plants and Epiphytic Bacteria Regarding Their Auxin Metabolism
Authors: Libbert Eike , Manteuffel Renate , Siegl Edda 
Published: April 2006

AbstractThe auxin content (extractable and ‘diffusible’ auxin) of non‐sterile corn plants is much more increased by a tryptophan application than the auxin content of sterile plants. This effect is independent of the mode of tryptophan application (spray or supply with the transpiration stream). The epiphytic bacteria settling the shoot surface are responsible for this effect, since in special experiments the rhizosphere was separated from the tryptophan treatment. Sterilized plants which were artificially reinfected with epiphytic IAA‐producing bacteria strains behave like non‐sterile plants. Non‐sterile plants which were superinfected with these bacteria strains have a still higher capacity to convert tryptophan to auxin.