bluuebunny/crossref_metadata_2025_split huggingface dataset:
Swelling in Bean Shoot Mitochondria Induced by a Series of Potassium Salts of Organic Anions
Authors: LEE DANIEL C. , WILSON RICHARD H. 
Published: April 2006

AbstractA series of potassium salts of organic anions were examined for their effect on the volume change of bean shoot mitochondria as measured by spectrophotometric light scatterings. A passive osmotic swelling (substrate independent) as well as an active osmotic swelling (substrate dependent) was shown with a series of organic anions. Both oxidizable substrates and non‐oxidizable substrates induce swelling. The monocarboxylic acids including acetate, β‐OH‐butyrate, propionate, and pyruvate induce active swelling which is partially inhibited by the presence of an ATP generating system or the uncoupler 2,4‐dinitrophenol (DNP). Dicarboxylic acids produce less extensive rates and amounts of active swelling. Moreover, the swelling induced by dicarboxylic acids is inhibited less completely by an ATP generating system or by DNP. Metabolizable substrates including citrate, pyruvate, glutarate, and α‐oxo‐glutarate induced swelling despite their poor rates or lack of oxidation. It was concluded that with these anions, penetration across the inner membrane as measured by osmotic swelling of isolated mitochondria is not the rate limiting step in their metabolism.
Short‐ and Long‐term Effects of High Temperatures (47–49 °C) on Tobacco Leaves. I. Photosynthesis
Authors: ZIONI ALIZA BEN , ITAI CHANAN 
Published: April 2006

AbstractDetached Nicotiana rustica leaves were exposed for 2 minutes to temperatures in the range 36° to 51°C. Above 45°C, 14CO2 fixation was reduced by half as compared with controls. The fall in 14CO2 fixation continued for 2 1/2 h. Recovery was completed 45 h after the treatment. Above 45°C there was an increase in the labeled cationic and anionic fractions and a decrease in the neutral fractions, both increase and decrease being associated with the impaired CO2 fixation. However, these changes in products were also demonstrated when leaves were exposed to the high temperature after labeling.
The Relationship between Exogenous Growth Inhibitors and Endogenous Levels of Ethylene, and Tuberization of Dahlias
Authors: BIRAN I. , GUR I. , HALEVY A. H. 
Published: April 2006

AbstractTreatments with abscisic acid (ABA), succinic acid‐2,2‐dimethylhydrazide (SADH), or 2 chlorethyl phosphonic acid (ethephon) promoted the tuberization of dahlia plants in long‐days. This effect was smaller, however, than the effect short days have on tuberization. In contrast, gibberellic acid (GA) treatments inhibited tuberization. SADH and ethephon treatments of budless leaf‐cuttings inhibited tuberization whereas ABA treatments slightly enhanced it. Evolution of endogenous ethylene reached a peak between the second and third week after the start of short‐day treatments, and then decreased to the low level found in plants growing under long days. The peak in ethylene evolution occurred one week before the onset of tuberization.
Recherches sur les enzymes catalysant la biosynthèse des acides phénoliques chez Quercus pedunculata. III. Formation séquentielle, à partir de la phénylalanine, des acides cinnamique, p‐coumarique et caféique, par des organites cellulaires isolés
Authors: ALIBERT GILBERT , RANJEVA RAOUL , BOUDET ALAIN 
Published: April 2006

AbstractThe reactions leading to cinnamic acids from phenylalanine as only substrate were investigated in organelles from Quercus pedunculata Ehrh. roots.–“F 10 000′” fraction, including mitochondria and micro‐bodies, catalyses the first reaction, i.e., cinnamate formation by deamination of phenylalanine.– Microsomal fraction catalyses all the steps from phenylalanine to caffeic acid via cinnamate and p‐coumarate. These results suggest that microsomes are the intracellular site of the cinnamic units synthesis. The enzymes involved in these reactions, associated in the same cellular compartment, does not form a multienzyme system. The formation of caffeic acid by isolated microsomes is demonstrated for the first time; the reaction may be realised by an enzyme different from phenolase.– The free phenolic acids are the metabolically active forms.
The Fate of Exogenously Applied Indoleacetic Acid in Light Grown Stems
Authors: DAVIES P. J. 
Published: April 2006

AbstractElongating segments from light grown pea (Pisum sativum L. cv. Alaska) and bean (Pbaseolus vulgaris L. cv. Red kidney) stems were incubated in 10‐5M indoleacetic acid (IAA)‐1‐14C,and ‐5‐3H in the light. Radoactive derivatives, extracted in water, ethanol or ether, and 1 N sodium hydroxide at three different times were chromatographed in three separate systems and the different metabolites identified by their labeling and chromatographic characteristics. Major metabolites included indoleacetyl aspartate, possibly indoleacetyl glucoside, hydroxymethyloxindole, and in bean a further major unidentified compund. Other compounds occurred in lesser amounts. Indole aldehyde was present only in very small quantities. IAA breakdown commenced between 1 and 6 h of incubation, following which IAA decreased and most metabolites increased, though IAA was still present after 24 h. Alkaline hydrolysates contained mainly IAA at a level which changed little between 6 and 24 h.
Morphogenetic Investigations in Callus Cultures of Tylophora indica
Authors: RAO P. S. , NARAYANASWAMI S. 
Published: April 2006

AbstractCallus cultures derived from stem explants of Tylophora indica (Fam. Asclepiadaceae) show a broad spectrum of tissue differentiation and regenerative potentialities over a wide range of nutrient conditions resulting in the production of roots, shoots, bipolar embryos and plantlets. This has been investigated and interpreted on a histological basis. Studies on the morphogenesis of embryos have shown that only such embryonal cells which were deeply embedded with in the callus parenchyma showed an ontogenic development reminiscent of ovular embryogeny whereas in those organized in the superficial layer of the callus the sequence of embryogeny was entirely different. Free cells growing in agitated liquid media first developed into filamentous structures and eventually, by repeated intercalary divisions, organized into bipolar embryos. Development of accessory embryos through cleavage and budding in the callus, differentiation of amphicribral vascular nodules, and meristematic colonies organized into spheres of parenchyma were also observed. These alternative morphogenetic events probably reflect the biochemical subtleties occurring within the callus as a result of an inadequacy or an imbalance of the various constituents in the culture medium.
Growth Hormones and Propagation of Cymbidium in vitro
Authors: FONNESBECH MOGENS 
Published: April 2006

AbstractProtocorms of Cymbidium (Orchidaceae) were grown on solid or liquid medium with macro‐nutrients according to Wimber (van Raalte 1967) and iron, micro‐nutrients and vitamins according to Nitsch (1968) the medium also contained 2% sucrose. The effects of 1) the auxins; indol‐3yl‐acetic acid (IAA), α‐naphthaleneacetic acid (NAA) and 2,4‐dichlorophenoxyacetic acid (2,4‐D); 2) the cytokinins; 6‐furfurylaminopurine (kinetin) and benzyladenine (BA) and 3) the gibberellin; gibberellic acid (GA) were examined alone or in combinations.IAA had no effect alone. NAA resulted in optimal fresh weight at 10 μM and the protocorms were vigorous, but lighter green than usual. 2,4‐D caused a high weight increase at 1 μM, but the protocorms were abnormal. Higher concentrations of NAA and 2,4‐D inhibited chlorophyll synthesis. On solid medium kinetin (100 μM) induced a growth of many small shoots, but had no effect on the fresh weight. In liquid medium, kinetin promoted a callus formation and fresh weight increase. BA had effects similar to kinetin, but at lower concentrations. GA alone promoted shoot and leaf growth.Combinations of kinetin and NAA resulted in a maximal fresh weight increase at kinetin concentrations one tenth of the NAA concentrations. The optimal growth and the best development occurred at 10 μM NAA and 1 μM kinetin. NAA and kinetin together could limit the shoot and leaf growth induced by GA.
Influence of Two Phenoxy Growth Regulators on the Uptake and Accumulation of Naptalam by Bean Plants
Authors: DEVLIN ROBERT M. , YAKLICH ROBERT W. 
Published: April 2006

AbstractBean plants (Phaseolus vulgaris L. cv. Black Valentine) treated with 2,4‐dichlorophenoxyacetic acid (2,4‐D) and 4‐chlorophenoxyacetic acid (PCPA) absorb and accumulate considerably more N‐1‐naphthylphthalamic acid (naptalam) than untreated plants. All concentrations of 2,4‐D from 5 x 10‐8 to 5 x 10‐4M were effective, peak stimulation occurring at 3 x 10‐5M. Plants treated with this concentration took up 186% more naptalam than control plants. It was shown that the leaf area (on a per g dry weight basis) was influenced most by growth regulator treatment. The leaf area of plants treated with 5 x 10‐5M 2,4‐D contained 575% more naptalam than the leaf area of untreated plants. The influence of PCPA on naptalam uptake by bean plants was similar to that of 2,4‐D but less effective.
The Effect of Plant Growth Substances on the Hyperchromicity of DNA
Authors: SPANG HENRY A. , PLATT ROBERT S. 
Published: April 2006

AbstractDeoxyribonucleic acid (DNA) was isolated from four day old, dark grown corn seedlings according to the procedure of Bonner for the isolation of chromatin followed by separation and purification according to Marmur. The purified DNA was dissolved in dilute saline‐citrate and the absorbance at 260 nm of the solution measured as the solution was slowly heated in a quartz cuvette. The degree of increase in absorbance of the DNA in solution as it is thermally denatured was used to assess the interaction of the DNA with plant hormones. Concentrations of 4 x 10‐5M NAA, IAA, 2,4‐D, and GA3 increased the hyperchromicity of the DNA when added to the DNA. Conversely, the same concentrations of CCC, AMO 1618, TIBA, and ABA decreased the hyperchromicity of the DNA. Kinetin, IAN, and tryptophan at 4 x 10‐5M had no measurable effect on the hyperchromicity of the DNA. Deoxyribonucleic acid from Escherichia coli and salmon sperm showed no change in hyperchromicity with added NAA at 4 x 10‐5M. The effect of these plant growth substances is most likely either on the thermally disrupted single strands or on the process in which the double strand opens up to single strands since only the high temperature portion was affected. It is postulated that if the plant growth substances act to alter the binding of the double strands of DNA in an isolated system and if this effect has a relationship to the DNA in an intact cell then this effect may be important in the control of plant growth and development.
The Effect of Photoperiod on Levels of Endogenous Cytokinins in Xanthium strumarium
Authors: VAN STADEN J. , WAREING P. F. 
Published: April 2006

AbstractThe cytokinin content of Xanthium strumarium L. plants decreased markedly when they were exposed to short days (SD). There was a significant decrease in the content of the butanol‐soluble cytokinins of the mature leaves after only 5 SD cycles, and after 10 SD there was no significant cytokinin activity in butanol extracts; the changes in the young leaves were less marked. Most of the cytokinin activity in mature leaves appears to be present in the aqueous fraction, whereas in young leaves most activity occurs in the butanol‐soluble fraction. SD treated plants produced less root exudate than LD plants, but there were no significant differences in the amounts of cytokinin in the root exudates from LD and SD plants collected over an equivalent time period. The cytokinin levels of SD‐induced leaves remained low even when transferred back to LD. The observed differences in cytokinin levels did not appear to be the result of photosynthetic differences. Exposure of detached leaves to LD or SD did not result in differences in cytokinin content. It is not clear whether the observed changes in cytokinin levels in the leaves under SD are involved in the flowering response, but they may be causally related to a reduced chlorophyll content observed in SD‐induced leaves.
Accumulation of (2,4‐dichlorophenoxy) acetic acid and (2,4,5‐trichlorophenoxy) acetic acid by Parenchyma Tissue as Influenced by Metabolic Inhibitors and Lecithin
Authors: SMITH A. E. 
Published: April 2006

AbstractParenchyma tissue from potato (Solanum tuberosum L. cv. Russet) tubers was treated with inhibitors to the release of metabolic energy in order to determine the importance of an active transport system for (2,4‐dichlorophenoxy)acetic acid (2,4‐D) and (2,4,5‐trichlorophenoxy)acetic acid (2,4,5‐T) accumulation. Results from treatments with carbonylcyanide m‐chlorophenylhydrazone, an inhibitor of oxidative phosphorylation, and N,N'‐dicyclohexylcarbodiimide, an inhibitor of membrane‐bound adenosine triphosphatase, indicated 2,4‐D and 2,4,5‐T accumulation to be independent of available energy as influenced by these metabolic inhibitors. Lecithin treated parenchyma tissue accumulated more 2,4‐D and 2,4,5‐T than untreated tissue indicating possible binding of the herbicide to the lecithin moiety.
Studies on the Physiology of Host‐parasite Relationship in Orobanche. III. Carbohydrate and Nitrogen Metabolism of Host and Parasite
Authors: SINGH JAGDISH NARAIN , RAI TEJ BAHADUR , SINGH JAI NARAIN 
Published: April 2006

AbstractDetermination of different carbohydrate and nitrogen fractions was made in tomato (Lycopersicum esculentum Mill.) and mustard (Brassica campestris L.) serving as hosts for Orobanche cernua and O. aegyptiaca respectively. Shoots of Orobanche were also subjected to such analyses. Infection raised the level of total reducing and total sugar in the host with a simultaneous decrease in the level of acid‐hydrolyzable and total carbohydrates in the constituent organs of infected hosts. This has been explained to be due to predominance of hydrolytic activity in the infected host. Infection also brought about a depression in the proportion of sucrose to the pool of total sugar in the host. This was also possibly due to predominance of hydrolytic processes and retardation in the synthetic processes. Higher concentration of acid‐hydrolyzable and total carbohydrates in Orobanche than in the host indicated a high demand for sugars by the parasite.The insignificant differences between the relative proportions of different nitrogen fractions to the pool of total nitrogen in healthy and infected hosts indicated that nitrogen metabolism was not deranged in any way due to infection. Orobanche always had a lower concentration of total soluble and total nitrogen than the host root.
Effect of 4‐Amino‐3,5,6‐trichloropicolinic acid on Protein Synthesis
Authors: BAUR J. R. , BOWMAN J. J. 
Published: April 2006

AbstractThe effects of 4‐amino‐3,5,6‐trichloropicolinic acid (picloram) on protein synthesis in bean (Phaseolus vulgaris L. cv. ‘Astro’) hypocotyl and hook tissues were studied. Picloram (10‐4M) was shown to have a stimulatory effect on 14C‐1‐DL‐leucine uptake in hook but not hypocotyl tissues. Maximum leucine incorporation and maximum total protein concentration occurred in hook tissues treated with 10‐4M picloram. Inhibition of protein synthesis with cycloheximide (CH) and erythromycin (ERY) indicates that endogenous and picloram‐stimulated protein synthesis is a function of the 80S cytoplasmic ribosomes rather than 70S chloroplast or mitochondria ribosomes.
Starch Metabolism, Respiration, and Shoot Formation in Tobacco Callus Cultures
Authors: THORPE TREVOR A. , MEIER DONALD D. 
Published: April 2006

AbstractThe starch content of shoot‐forming and non‐shoot‐forming tobacco callus cultured in light and darkness was determined. A variety of carbohydrates and cytokinins incorporated into the culture medium were effective in bringing about starch accumulation and shoot formation in the tissue. In addition, the respiratory activity of the callus, grown in the presence or absence of gibberellic acid, was measured. A strong correlation between the starch content of the tissue, its rate of respiration, and shoot formation was observed.
Titration with 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU) as Evidence for Several Photophosphorylation Sites in Scenedesmus
Authors: KYLIN A. , SUNDBERG I. , TILLBERG J.‐E. 
Published: April 2006

AbstractPhotophosphorylation was measured in intact cells of Scenedesmus obtusiusculus, which were made phosphate starved before the start of the experiments. Photophosphorylation was titrated with narrow intervals of 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU) from 10‐7M upwards. Plots of the reciprocal of photophosphorylation against concentration of DCMU gives three essentially straight lines; one between 10‐7 and 10‐6M DCMU; one between 10‐6 and 6 · 10‐6M DCMU; and one for more than 6 · 10‐6M DCMU, the last‐mentioned line being parallel to the abscissa. The stoichiometry between the three reactions is roughly 2: 1: 1. At least three sites for photophosphorylation are indicated, and the assumption that all sites work with approximately the same efficiency would make them four.
Translocation of Shoot‐Applied Indolylacetic Acid into the Roots of Populus tremula
Authors: ELIASSON LENNART 
Published: April 2006

AbstractApplication of 10 to 100 μg indol‐3‐ylacetic acid to the leaves of rooted cuttings of aspen caused inhibition of root growth after three hours. Root growth recovered within 24 hours after IAA treatment. Swelling of the root tips occurred during the period of inhibition. The roots responded in the same way if IAA was applied in solution to the cut stem surface above the mature leaves.IAA‐1‐14C applied through a cut stem surface or to mature leaves was translocated downwards in the plants and labelled IAA could be isolated from the roots 3 to 24 hours after application. The ethanol‐soluble activity decreased rapidly indicating a rapid metabolism or binding of IAA. IAA‐1‐14C applied to growing leaves was not translocated.From the rapid response of root growth it was concluded that IAA was translocated into the roots at a rate of about 7 cm per hour. This rate of translocation indicates that the sieve tubes are involved in the translocation. Implications of the results for the translocation of endogenous auxin into the roots are discussed.
Cyclic Purine Mononucleotides: Induction of Gibberellin Biosynthesis in Barley Endosperm
Authors: KESSLER BEZALEL , KAPLAN BINA 
Published: April 2006

AbstractThe de novo synthesis of α‐amylase in barley endosperm and isolated aleurone layers is induced by 3′,5′‐cyclic purine mononucleotides and gibberellic acid.The induction of α‐amylase by cyclic purine mononucleotides is prevented by 2,4‐DNP, inhibitors of RNA and protein syntheses, CCC, AMO‐1618 and phosfon. The induction of α‐amylase formation by 3′,5′‐cyclic purine mononucleotides, but not by gibberellic acid, is also blocked by inhibitors of DNA synthesis.Extracts from cyclic AMP‐treated endosperm halves exhibit a characteristic gibberellin‐like activity which is detectable within 12 hours from the addition of the cyclic AMP. On paper chromatograms this gibberellin‐like activity is located at the Rf typical for GA3. Its formation is prevented by inhibitors of DNA synthesis, CCC and AMO‐1618.Glucose inhibits the formation of α‐amylase induced by gibberellic acid. Glucose has no effect on the cAMP‐induced gibberellin biosynthesis.The evidence shows that the cyclic purine mononucleotides induce DNA synthesis, which results in gibberellin biosynthesis, which in turn activates the synthesis of α‐amylase.
The Regulatory Role of Inflorescence Leaves in Fruit‐setting by Sweet Orange (Citrus sinensis)
Authors: MOSS G. I. , STEER B. T. , KRIEDEMANN P. E. 
Published: April 2006

AbstractInflorescence leaves improve fruit set on sweet orange trees. We sought an explanation for this effect in terms of carbon demand by developing fruit versus potential supply from adjacent leaves. Our assessment was based upon measurements of fruit growth, leaf photosynthesis and 14C distribution patterns in plants grown under controlled conditions.Leafy inflorescences had sufficient foliar surface (1.24 dm2) and photosynthetic capacity (CO2 10.1 mg · dm‐2· h‐1) to support early development of fruits on the same shoot, and to make a substantial contribution towards subsequent growth. 14C‐assimilates derived from new leaves were distributed towards adjacent fruit which showed strong competition for labelled substrate.By contrast, fruit borne on leafless inflorescences had to obtain all their assimilates from older leaves whose photosynthetic capacity (CO2 3.5–4.6 mg · dm‐2· h‐1) and individual area (0.2 dm2) were generally insufficient to wholly sustain fruit growth, so that a large number of old‐leaves were needed; these fruit would be more susceptible to competition from other sinks.
14C‐Studies on Apple Trees. VIII. The Seasonal Variation and Nature of Reserves
Authors: HANSEN POUL , GRAUSLUND JØRGEN 
Published: April 2006

AbstractThe nature, seasonal variation and mobilization of reserves in Malus × domestica have been studied by means of 14C, carbohydrate analyses and extractions of xylem sap.Following exposure to 14CO2 in the autumn, the majority of the 14C absorbed is found in the root. During the winter and in particular the spring the amounts of 14C in the top and root are reduced to approximately 40 per cent of the autumn values; in the root the amount of dry matter was also considerably reduced. In the tops, most of the 14C absorbed was found as methanol (80 %)‐soluble 14C which also showed the greatest seasonal reduction; sorbitol, sucrose or glucose in particular are responsible for the decrease in concentration within this fraction. Maximum values for methanol‐insoluble 14C were found in March. In the root, the highest values for absolute changes were found for methanolinsoluble 14C. Hydrolysis of this fraction showed considerable activity in glucose. In the root there was also considerable activity in a precipitated fraction of the methanol extract.Eluates of xylem sap from apple branches contained primarily sorbitol, the highest concentration of which was found at the beginning of March.For a tree with a dry matter weight of about 300 g, the utilization of reserves from the tree in the spring was calculated to be at least 13 g of dry matter. However, only a minor part (less than 25 per cent) of the latter appears to serve as building material for new growth.
Protoplast Cultures from Cell Suspensions of Daucus carota
Authors: WALLIN ANITA , ERIKSSON TAGE 
Published: April 2006

AbstractProtoplasts, enzymatically isolated from cell suspension cultures of Daucus carota, have been grown in small Petri‐dishes. After enzyme treatment and washing the protoplasts were plated in agar media. Growth and divisions were viewed through the bottom of the Petri‐dishes with a light microscope. Different osmotic stabilizers were tested with respect to their ability to promote wall formation and growth of the protoplasts. Combinations of sucrose, sorbitol and “Modopeg” gave the best results. Electron micrographs of cultured protoplasts revealed normal as well as abnormal nuclear conditions.
Rhizomorph Formation in Fungi
Authors: ALLERMANN K. , SORTKJÆR O. 
Published: April 2006

AbstractThe effect on growth and rhizomorph formation of 12 alcohols (methanol, ethanol, 1‐propanol, 2‐propanol, 1‐butanol, 2‐butanol, iso‐butyl alcohol, tert‐butyl alcohol, 1‐pentanol, iso‐amyl alcohol, ethylene glycol and glycerol) at different concentrations has been examined for 2 isolates of Armillaria mellea (Vahl ex Fr.) Quél. and 1 of Clitocybe geotropa (Bull. ex Fr.) Quél. The fungi were cultivated for 28 days on a synthetic, liquid glucose medium with the alcohols as supplement.The following alcohols strongly stimulated growth and rhizomorph formation: ethanol, 1‐propanol and 1‐butanol. A great variation was demonstrated between the isolates in relation to rhizomorph production, morphology, and ability to be stimulated by different alcohols.