bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of Mitochondrial Complementation
Authors: McDaniel Robert G. , Sarkissian Igor V.
Published: April 2006

Mitochondrial complementation (enhancement of oxidative activity of mitochondrial occured when mitochondria of some inbrveds of eron were mixed in vitro. It was found that mixtures composed of various proportions of mitochondria of inbreds exhibited complementation. Extracts of mitochondria of one inbred did not promote complementation when they were added to infact mitochondria of inbreds exhihited complententation. Extracts of mitochondria of on einbred did not promote complementation when they were added to infact mitochondria of the second inbred. Serial dillutions of mixtures resulted in a rapid reduction of mitochondrial oxidation (QO2 N) suggesting that intimale association between mitochondria was minimized by the dilution and that this decreased complementation. Similar dilutions of mitochondria from inbreds did not decrease their specific activity. Kinetics of mitochondrial oxidation were measured polarographically and it was found that complementation was measurable immediately (1 min) following the mixing. This suggested that physical contact between mitochondria was necessary for complementation.
Auxin‐induced Growth of Helianthus Tuber Tissue V. Role of DNA synthesis in hormonal control of cell growth
Authors: Kamisaka Seiichiro , Masuda Yoshio
Published: April 2006

The role of DNA synthesis in hormonal control of cell growth was studied, using tissue slices excised from cold‐ stored Helianthus tubers.

Metabolic inhibitors of DNA synthesis such as 5‐fluorodeoxyuridine and phenethyl alcohol inhibited the effect of auxin and gibberellie acid on expansion growth, the latter being given during the aging period. The inhibitory effect of 5‐fluorodeoxyuridine on expansion growth was alleviated by the simultaneous addition of thymidine but not by that of uridine.

Incorporation of 14C‐thymidine into DNA occurred during the aging period and gibberellic acid stimulated the incorporation of 14C‐thymidine into DNA when given during the aging period. Mitomycin C and 2‐(chloroethyl)‐trimethyl‐ammonium chloride (a growth retardant) inhibited incorporation of labelled thymidine into DNA.
On the Nature of the Heat Resistance of Thermophilic Bacteria
Authors: Ljunger Claes
Published: April 2006

The importance of inorganic ions for the heat stability of thermophilic bacteria was investigated. Cells of Bacillus stearothermophilus, strain 1503, were incubated at elevated temperatures in various media and the number of surviving organisms was determined at suitable intervals. The bacteria rapidly died at temperatures ordinarily employed for their cultivation if the surrounding medium lacked calcium ions. Besides calcium ions, potassium and phosphate ions and glucose, or some other energy source, seemed to be required for the heat stability of the cells. A chemically defined stabilizing medium with these components was developed for the above‐mentioned strain. When any component of this medium was excluded, the heat resistance of this organism was lost. This medium had a stabilizing effect also on the cells of three other strains of B. stearothermophilus. These requirements suggest that the heat stability of thermophilic bacteria is attributable to an active transport of calcium ions from the environment into the cells.
Studies on the Germination of Pine Pollen (Pinus mugo) in vitro. II. Effects of Different Ions
Authors: Nygaard Per
Published: April 2006

Studies 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

The 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

Photoinduction 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

The 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

Excised 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

Changes 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

Four 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

With 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

Growth 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

Kinetin‐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

Sugarcane 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

Leaf 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

The 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 10‐4–10‐3M

None 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

The 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

The 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

The 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

Plants 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

Treatment 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

Four 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

Auxin 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

The 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.
14C‐Studies on Apple Trees. VI. The Influence of the Fruit on the Photosynthesis of the Leaves, and the Relative Photosynthetic Yields of Fruits and Leaves
Authors: Hansen Poul
Published: April 2006

When paired samples of either intact or detached apple shoots with and without fruits were exposed simultaneuosly to 14CO2, the uptake of 14CO2 of leaf area was found to be greater in the fruit‐bearing shoots, often by a factor of 1.5 or more, although the difference tends to be slight or even non‐existent when the experiments follow shortly after a previous dark period.

The uptake of 14CO2 by photosynthesis in the skin of detached fruits is very slight compared to the simultaneous uptake of 14CO2 by the leaves from the same spur, and can hence contribute only slightly to the development of the fruit compared with the supply of assimilates taking place from the leaves to the fruit.
Indole‐3‐acetic Acid Oxidase in a Nicotiana Hybrid and its Parental Types
Authors: Meudt Werner J.
Published: April 2006

The metabolism of IAA is correlated with tumor formation in the Nicotiana hybrid, N. glauca x langsdorffii. Higher IAA‐oxidase activity was found in leaves of hybrid plants than in leaves of parental types. Furthermore, topographical distribution study revealed that young expanding leaves contained more IAA‐oxidase activity than older leaves. In hybrid plants, there is a close correlation between IAA‐oxidase activity and the ability of a leaf to produce tumors. Leaves which yield the greatest number of injury‐induced tumors also yield the highest IAA‐oxidase activity. IAA incites callus‐like outgrowths in hybrid plants which do not differentiate into a multitude of apices as is the case with spontaneous tumors.

The results are interpreted on the basis of a concept that the IAA‐oxidase system in plants may function as part of an IAA activating mechanism rather than in the basis of an IAA destroying system.
The Action of Some Cytokinins on the Rest‐period and the Content of Acid Growth‐inhibiting Substances in Potato
Authors: Hemberg Torsten
Published: April 2006

Apical sections of resting potato tubers of the variety Majestic, which is known for a long rest‐period, were treated for 6 and 24 hours with water or with the cytokinins kinetin or zeatin. The cytokinin‐treatment breaks the rest‐period very rapidly. The buds begin to sprout already after 2–3 days. The content of acid inhibitors (the β inhibitor) in extracts of the peelings from cytokinin‐treated sections in much lower than in similar extracts from water‐treated, resting sections. Already 6 hours after the beginning of the treatment, differences in inhibitor content can be demonstrated.
Modalités de l'inhibition de la croissance et de la synthèse des acides nucléiques des plantules de blé par l'acide abscissique
Authors: Belhanafi A. , Collet G. F.
Published: April 2006

The growth of wheat seedlings (Triticum sativum) is inhibited by abscisic acid (ABA). The inhibition increases with the concentration of ABA (from 10‐6M to 5 × 10‐5M) and is stronger in the case of coleoptiles and first leaves than in roots. In contrast, naphthaleneacetic acid (ANA), at 10‐5M, exerts its greatest inhibitory effect on the roots. The inhibitory effect of ABA on coleoptiles can be partially overcome by kinetin and to a much smaller degree by gibberellic acid. Neither of these two compounds, at 10‐5M, had any effect on the ABA‐induced inhibition of root growth. The RNA and DNA contents per plant organ are considerably reduced after treatment of the seedlings with ABA, particularly in the coleoptiles and the first leaves. The incorporation of uracil‐2‐14C and uridine T (G) into RNA of treated seedlings is reduced in the case of coleoptiles and first leaves, but considerably enhanced in roots. The mechanism of the action of ABA is discussed in the light of these results.
The Influence of Accompanying Cations on the Foliar Uptake of Na, K, Rb and Cs
Authors: Levi E.
Published: April 2006

The influence Na, K, Rb or Cs may have when accompanying one of these elements applied foliarly to bean plants has bean studied under controlled environmental conditions. No competition was found in the speed of initial penetration from the outer leaf surface to the protoplasts of epidermal cells between any two of the cations considered separately. The magnitude of penetration of Na, Rb or Cs. Retention in the treated area showed competition among the elements, Na being held more strongly when accompanied by Cs, Rb or K in that order. Presence of another cation influenced retention differently. Transport of Na was faster than of either K, Rb or Cs when applied together. K and Rb were transported simultaneously at equal rates, and either more than Cs. Total quantities transported were influenced differently by the various cations present and in turn determined the total quantities taken up by the plants.
Properties of β‐Galactosidase from Verticillium albo‐atrum
Authors: Keen N. T.
Published: April 2006

An intracellular, inducible β‐galactosidase [EC 3.2.1.23] was partially purified from Verticillium albo‐atrum. The activity was associated with a particle of about one million molecular weight and required polyhydroxyl compounds for stabilization and activation. It was inhibited by various sulfhydryl inhibitors and EDTA. The latter inhibition could be overcome by adding Mn2+ to reaction mixtures. The β‐ galactoside (ONPG) activity toward lactose (apparent Km= 0.08 M) and o‐nitrophenyl‐β‐D‐galactoside (ONPG) (apparent Km= 2×10‐23M) purified in parallel. Lactose competitively inhibited the degradation of ONPG with a Ki of 0.1 M. When activated by glycerol, the enzyme produced not only glucose and galactose from lactose, but also other unidentified products, perhaps by transglycosylation.
The Effect of Ascorbic 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

Plants 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 ascorbic acid (20 mg/l and 100 mg/l) 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.

Ascorbic acid (AA) treatments considerably enhanced nodule initiation. AA was found to increase the number and the fresh and dry weights of nodules tremendously and maximally under both concentrations used. The nodules were, on the whole, more pink under AA treatments and their greening was considerably delayed thus increasing their functional span. The nitrogen content of AA‐treated plants was over 2.5 times that in the control. This increase in nitrogen content fully reflected itself in growth by an increase in the weight of all plant organs. Treatment with 20 mg/l AA stands out prominently above all others in this respect. Pod formation started earlier and the pod and seed weights were also much higher in the AA treatments than in the control. Treatment with 20 mg/l AA was on the whole more promotive than that with 100 mg/l.

The enhancement in the nodulation and the functional efficiency of nodules by AA treatments has been attributed to the capacity of AA to increase the loci and rates of cell division by promoting nucleic acid and protein synthesis and its action as a powerful electron donor. The results show that nodulation is yet another phenomenon wherein AA plays the role of an important hormone.
Ammonium and Salt Inhibition of Some Physiological Processes Associated with Seed Germination
Authors: Barker A. V. , Maynard D. N. , Mioduchowska Barbara , Buch Anna
Published: April 2006

Seed germination was totally inhibited by high (0.1 N) concentrations of potassium or ammonium salts. Partial inhibition of germination occurred with low (< 0.01 N) concentrations of ammonium salts, but low concentrations of potassium salts did not affect germination. Except with extreme salt or ammonium injury, the inhibition of germination was at least partially reversible. Respiration of germinating seeds was inhibited by both species of salts. Seedling development was severely impaired by ammonium salts, but not by potassium salts.
Effects of Abscisic Acid on Phenolic Content and Lignin Biosynthesis in Tobacco Tissue Culture
Authors: Li H. C. , Rice E. L. , Rohrbaugh L. M. , Wender S. H.
Published: April 2006

A significant depression of callus growth resulted from low concentrations of abscisic acid (ABA) added to the medium recommended by Linsmaier and Skoog. Low concentrations also decreased the chlorogenic acid and lignin content of the callus, and generally decreased amounts of scopolin and scopoletin in the tissue. Gibberellic acid (GA3) stimulated callus growth in a low concentration (0.1 mg/1) and inhibited growth at a high concentration (10.0 mg/1). Both levels of GA3 increased scopoletin accumulation in tobacco callus. A high concentration of GA3 increased the accumulation of scopolin and chlorogenic acids, whereas a low concentration decreased the amounts of these two phenolic compounds. In comparison with the control, lignin synthesis was stimulated by a low GA3 concentration, but a high GA3 concentration did not have a significant effect. Both low and high concentrations of GA3 overcame ABA inhibition of growth and lignin synthesis, and partially reversed ABA inhibition of scopoletin production. However, GA3 did not reverse the inhibitory effect of ABA on scopolin production. The low concentration of GA3 overcame the inhibition of chlorogenic acid production resulting from a 0.01 mg/1 concentration of ABA, but this was the only reversal of chlorogenic acid inhibition resulting from addition of GA3 to the medium.
Studies on the Destruction of Indole‐3‐acetic Acid by a Species of Arthrobacter. V. Indole‐3‐acetic Acid Production from Tryptophan
Authors: Mino Yǒcsuke
Published: April 2006

Tryptophan (Try) metabolism of Arthrobacter sp. was examined. The inducibility of the Try oxidizing enzyme system seems to be correlated with that of the indole‐3‐acetic acid (IAA) oxidizing enzyme system. Try is metabolized to IAA via indole‐3‐pyruvic acid (Ip) and indole‐3‐acetaldehyde (IAAId). Indole‐3‐acetamide (IAm) is formed as a product of Try oxidation. Exogenous IAm, indole‐3‐acetonitrile (IAN) and tryptamine are not oxidized by Try‐induced cells.
Control of Stem Elongation and Flowering in Scrophularia marilandica
Authors: Cline Morris G. , Agatep Aurora O.
Published: April 2006

The influence of temperature, photoperiod. and certain metabolities was determined for stem elongation and flowering in Scrophularia marilandica. Induction for flowering did not occur until several weeks after the beginning of rapid stem elongation. From the experiments reported it is concluded that S. marilandica is a high‐temperature quantitative long‐day plant. Temperatures above 20°C negate the absolute requirement for long days for flowering. Plants exposed to photoperiods as brief as 4 hours flowered, given high temperatures. Stem elongation was found to be a necessary prerequisite for flowering. The process of stem elongation was somewhat more sensitive to inhibition by low temperatures than flowering and to a great extent more sensitive than leaf formation and leaf growth. Vernalization was found to be unnecessary for stem elongation and flowering. Gibberellic acid promoted stem elongation and branching without flowering under conditions resembling cool short days. Other metabolities were tested but had no observable effects.
Phytochrome Controlled Adhesion of Mung Bean Root Tips to Glass: A Detailed characterization of the Phenomenon
Authors: Yunghans H. , Jaffe M. J.
Published: April 2006

Various parameters of the Tanada effect (Proc. Natl. Acad. Sci. U.S. 59: 376–380. 1968) have been defined. This phenomenon, in which root tips of Phaseolus aureus L. adhere to a negatively charged glass surface when they are irradiated with 660 nm (red) light and release under 730 nm (far‐red) light, has been characterized as follows.

Secondary roots, whether etiolated or light grown exhibit photoreversible adhesion. Primary roots do not. Tips from 6–8 mm secondary roots exhibit the best response to red light, whereas tips from 3 mm roots respond best to far‐red light. Red light saturetes the adhesion system at about 50 μ W/cm2xnm and far‐red light, release system at about 150 ü W/cm2 xnm. The adhesion effect begins to show escape from far‐red reversibility within 60–90 seconds, an observation quite different from other “typical” long term de‐ etiolation effects. In addition, root tips irradiated with red light begin to release spontaneously in the dark after 10 min, and have nearly completed release after 50 min. Tips irradiated with continuous red light show gradual release after 15 minutes of exposure. Whether these data indicate an extremely rapid dark reversion of Pfr to Pr or decay of Pfr under continuous red light is not known at this time.

In order to study tip adhesion and release, the glass beaker surface may be negatively charged with thiocyanate (SCN‐), nitrate (NO3‐), sulfate (SO42‐), chloride (Cl‐), phosphate (PO43‐), citrate (C6H5O73‐), oxalate (C2O42‐) or glutamine (C5H8NO4‐). Benzoate (C7H5O2‐) and acetate (CH3COO‐) were found to be relatively ineffective for red light adhesion, however when citrate and oxalate were used release was inhibited. This was apparently due to a chelation of Ca2+since release began immediately as excess Ca+2 was added to the bathing solution.

Substitution of GTP, ITP, UTP, or CTP for ATP resulted in only 20 to 40% adhesion and release for GTP, ITP and UTP, CTP showed normal adhesion kinetics under red light but very slow release kinetics under far‐red light.

The effects of red and far‐red light in the numbers of secondary roots are that red light inhibits root initiation while far‐red light partially reverses the red light effect.
Influence of Shading on the Gross Composition of Cuscuta Species on Medicago sativa
Authors: Setty Pravina N. , Krishnan P. S.
Published: April 2006

A study was made of the alterations in growth characteristics of Cuscuta Campestris, Cuscuta indecora and Cuscuta reflexa on Medicago sativa as a consequence of a limitation in light intensity. There was a decrease in the content of dry solids, protein and total phosphorus in the filament mass. A decrease in these parameters occurred also in the tissues of the host, but was less pronounced that in the parasite. The response by the host to parasite growth was not always the same in the shade as in light. Phosphorus showed a distinct tendency toward firm retention in the infection complex in the dark.
Heterogeneity in Composition along the Length of Cuscuta filaments
Authors: Misra P. C. , Setty P. N. , Singh D. V. , Lal R. K. , Viswanathan P. N. , Saxkna Y. R. , Krishnan P. S.
Published: April 2006

Considerable variations in the content of free amino acids, elhanol‐soluble carbohydrates, starch, protein, chlorophyll, phylic acid, RNA and DNA exist in different regions of the long filaments of Cuscuta reflexa. The distinction is especially pronounced when comparison is made between the hanstoria‐bearing curls of the parasite and the apical portions of the overhanging filament.
Correlations between Nitrate Reduction, Protein Synthesis and Malate Accumulation
Authors: Ben‐zioni Aliza , Vaadia Y. , Herman Lips S.
Published: April 2006

The reduction of nitrate in leaves establishes an ‘excess’ of cations in the tissue which is rapidly neutralized by the synthesis of malate. Malate synthesized in nitrate‐containing leaves accumulates while malate synthesized in nitrate‐depleted leaves disappears gradually. The levels of nitrate reductasc and malate synthesis change similarly during leaf growth. Good correlation was also found between the rate of protein synthesis and the rale of malate synthesis. Stoichiometric relation between the amount of nitrate reduced and malate accumulated may be observed in short‐term experiments.
Growth Response to Cyanide by Plants Grown in the Presence or Absence of Iron
Authors: Israelstam G. F.
Published: April 2006

Seedlings of Phaseolux vulgaris were grown in media with and without iron. Growth was measured in terms of leaf length and fresh weight increase. Cyanide at & concentration of 0.05 mM was found to inhibit severely plants growing in complete media but failed to inhibit growth to (he same extent in those plants grown in media lacking iron. It was established that this result was obtained whether the plants were grown in an unchanged medium or if the growth medium was replaced at intervals. A number of suggestions were made in an attempt to account for this anomalous behavior.
Effect of Gibberellin A3 on the Elongation, α‐Amylase Activity, Reducing Sugar Content and Oxygen‐uptake of the Leaf Sheath of Dwarf Maize Seedlings
Authors: Katsumi Masayuki
Published: April 2006

GA3‐treatment of dwarf maize seedlings resulted in the elongation of the leaf sheath and also an increase in α‐amylase activity. Excised leaf sheaths did not respond to GA3 in leaf shealh length and α‐amylase activity. Increase in the enzyme activity is always accompanied by an increase in the length of the leaf sheath. α‐Amylase activity gradually increased as the growth of the first leaf proceeded, and a parallelism was found between the length of the leaf sheath and the enzyme activity, suggesting that the degree, of the enzyme activity depends on the length of the leaf sheath. On the other hand, IAA did not affect α‐amylase activity while it promoted leaf sheath elongation. This suggests that elongation per se is not associated with the increase in α‐amylase activity and that the enzyme‐promoting effect is specific to gibberellin. Higher α‐amylase activity and lower content of reducing sugars were detected in the older tissue of the leaf sheath, that is, in the upper half. This was the same for GAlrealed seedlings. The amount of reducing sugars was less in GA3‐trealcd seedlings. Oxygen‐uptake of the leaf sheath was higher in the upper half in both controls and GA3‐treated seedlings. It was slightly higher in the latter than in the former. From these results it was discussed 1o conclude that the processes of the GA3‐induced elongation and increase in α‐amylase activity of the leaf sheath are independent of one another.
The Role of Sucrose and Fructosylsucrose in Fructosan Metabolism
Authors: Pontis Horacio G.
Published: April 2006

Explants of mature dormant tubers of Helianthus tuberosus were grown in a glucose medium. The explants were able to initiate a de novo synthesis of fructosans. Initiation of this synthesis depends on the level of sucrose and fructosylsucrose. Sucrose synthetase level in the tissue can be altered by 2, 4‐D. Fructosylsucrose synthetase seems to be induced by sucrose.
Chemical Changes Associated with the Breaking of the Rest Period in Vegetative Buds of Pyrus communis
Authors: Chaudhry Wali M. , Broyer T. C. , Young L. C. T.
Published: April 2006

Buds of heat and cold treated shoots were examined for their soluble and insoluble nitrogen, lipid‐P, ester‐P, RNA‐P, DNA‐P, phosphoprotein‐P, inorgnnic‐P. and total‐P contents. Results indicated a direct relationship of bud growth with insoluble‐N, ester‐P and RNA‐P concentrations. Decrease in phosphoprotein‐P was found to be concomitant with increase in RNA‐P.

Various postulates have been considered in the light of the present results and those of others. A pathway of action in budrest break has been proposed which assumes that rest‐breaking treatments cause liberation of DNA from a DNA‐phosphoprotein‐complex, which latter determines the resting slate. The freed DNA then acts as a template for RNA synthesis. This increased RNA synthesis coupled with increased ATP content (inferred from ester‐P levels) induce protein synthesis (inferred from insoluble‐N) and bud rest is broken.
Effect of Morphactin on the Gravimorphism and the Uptake, Translocation and Spatial Distribution of Indol‐3yl‐acetic Acid in Plant Tissues in Relation to Light and Gravity
Authors: Parups E. V.
Published: April 2006

The changes in geo‐ and photolropism exhibited by plants trealed with morphactin, the methyl‐2‐chloro‐9‐hydroxyfluorene‐(9)‐carboxylic acid, have been explained as inhibition of the basipetal and promotion of the acropetal and lateral transport of indol‐3yl‐acetic acid and the equalization of its levels in horizontally placed plant tissues. The geotropical unresponsiveness of morphactin treated corn coleopliles appeared to be related to the distribution and immobility of starch grains acting as geosensors.

The author is indebted to Dr. J. E. Fisher for advice and Mr. W. Richards for his technical assistance.