bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractWhen 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

AbstractThe 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

AbstractApical 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

AbstractThe 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

AbstractThe 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

AbstractAn 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

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 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

AbstractSeed 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

AbstractA 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

AbstractTryptophan (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

AbstractThe 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

AbstractVarious 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

AbstractA 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

AbstractConsiderable 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

AbstractThe 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

AbstractSeedlings 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

AbstractGA3‐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

AbstractExplants 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

AbstractBuds 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

AbstractThe 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.
Effect of Temperature of the Culture Medium on Growth and Nitrogen Fixation of Inoculated Legumes and Rhizobia
Authors: Roponen Ilma , Valle Eero , Ettala Terttu 
Published: April 2006

AbstractTwo pea (Pisum sativum L.) cultivars and a kidney bean (Phaseolus vulgaris L.) cultivars were grown in water cultures at different diurnal temperatures (15, 20, 24, 27, 30°C) or at 10°C night temperature combined with various day temperatures (20, 24, 27, 33 or 35°C) in the root medium. The inoculated plants were, more sensitive to the extreme temperatures than the plants supplied with combined nitrogen (KNO3). The middle‐European pea cv. Violetta was adapted to somewhat higher root temperatures than the northern one cv. Torsdag II, the latter showing better growth at lower temperatures, when the plants were inoculated with the same Finnish Rhizobinm strain (HA1). Especially at optimum day temperatures the nitrogen fixation and consequently the dry weights of the inoculated plants were greatly increased when the night temperature was lowered.The optimum temperature for the growth of free‐living Rhizobium strains (HA1 and H43) for peus was found to be 25°C and that of a strain (P103) for beans somewhat higher.Effective nitrogen fixation by nodulated legumes without a supply of combined nitrogen is achieved only when the optimum temperature range for root function is very close to the optimum for the rhizobia.
Investigations on Cytokinins. IV. The Metabolism of 6‐Benzylaminopurine in Lemna minor
Authors: BEZEMER‐SYBRANDY SYTSKE M. , VELDSTRA H. 
Published: April 2006

AbstractThe metabolism of 14C‐labeled 6‐benzylaminopurine in aseptic cultures of Lemna minor was investigated. This cytokinin is slowly taken up by the plants; part of it can be released and part of it is rapidly metabolized to several compounds, among which the corresponding nucleotides can be identified. In this connection the feasibility of locating the site of hormone receptors (sites of primary action) in plants is discussed. Incorporation of the labeled cytokinin into Lemna tRNA was not observed, although tRNA hydrolysates, isolated from plants grown on a cytokinin‐free medium, contain a fair amount of cytokinin activity and therefore presumably cy okinin molecules.