bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Laboratory Method Used for Investigating the Uptake, Translocation and Metabolism of Bark Banded Morphactin by Trees
Authors: NEUMANN PETER M. , DOSS ROBERT P. , SACHS ROY M. 
Published: April 2006

AbstractCut twigs of Monterey pine(Pinus radiata D.Don) were banded with a 14C labelled morphactin formulation and the lower half of the twig placed in a Scholander type pressure bomb. Water was pumped through the twig from a reservoir inside the bomb and exudate collected from the protruding end of the twig. Using this method it was possible to determine that the slowest step in the translocation of morphactin was the passage across the outer layer of bark. Subsequent passage through the twig was not affected by girdling the bark suggesting that morphactin was translocated upwards via the xylem. The 14C compound in the exudate from live twigs differed from morphactin and was tentatively identified as the carboxylic acid derivative of the morphactin ester.The cut twig system facilitated studies on the uptake, metabolism and translocation of morphactin and should prove useful for studying the uptake and fate of other chemicals considered for bark application to trees.
Effect of Gibberellic Acid, (2‐Chloroethyl) Phosphonic Acid, Actinomycin‐D and Cycloheximide on the Activity and Leaching of Some Hydrolases in Pollen Suspension Cultures of Crotalaria juncea
Authors: BHANDAL IQBAL SINGH , MALIK C. P. 
Published: April 2006

AbstractGibberellic acid (GA3) 20 mg 1−1 and (2‐chloroethyl) phosphonic acid (Ethephon) 10 mg 1−1 enhanced pollen tube length in Crotalaria juncea L. GA3 markedly increased the activity of amylase, acid phosphatase and β‐glucosidase and enhanced leaching of amylase and acid phosphatase enzymes. The rise in the activity level and leaching of amylase and acid phosphatase after Ethephon treatment was comparatively less than that of GA3 and the response to Ethephon was restricted to the 45 and 90 min period of culturing. Ethephon did not affect the activity/leaching of β‐glucosidase significantly. Actinomycin‐D (Act.D) 25 mg l−1 and Cycloheximide (CH) 10 mg 1−1 reduced the tube growth as well as activity of these enzymes suggesting their de novo synthesis during pollen tube growth.
The Threshold Stimulus for Geotropism
Authors: JOHNSSON ANDERS , PICKARD BARBARA G. 
Published: April 2006

AbstractThe minimum effective geotropic stimulation time is very short for coleoptiles, hypocotyls and roots. New data from the literature are used to emphasize that the minimum time is of the order of 10–20 s. The existence of such a short minimum time should be carefully considered in the design of geotropic experiments in Spacelab, which are now at the planning stage. Even brief acceleration periods at 1 g or less during a flight might cause unintentional geotropic effects.The short minimum stimulation time also has relevance for the statolith theory: since the distance which an amyloplast can sediment during this time is very small, no long sedimentation distance is likely to be required for georeception. Moreover, the magnitude of thermal noise must be considered in evaluating proposals for the georeceptive mechanism.
Osmotic Adaptation in Panicum repens. Differences Between Organ, Cellular and Subcellular Levels
Authors: RAMATI A. , LIPHSCHITZ NILI , WAISEL Y. 
Published: April 2006

AbstractThe process of osmotic adaptation was studied in leaves of Panicum repens. Two phases were observed: the first phase, which continued for 2–4 days, was mainly characterized by dehydration of leaves, a fast synthesis of organic acids and penetration of sodium into leaf cells. Chloride becomes dominant in the leaves only from the third day of exposure and onwards. The second phase of adaptation lasted for 4–6 days. During this phase, a decrease in organic acid content and an increase in leaf‐chloride content was observed. In spite of the fact that the osmotic potential of the leaves reached lower values than that of the external medium already after 2 days, the rate of growth of the plants was hampered. Such inhibition of growth disappeared 6–8 days after exposure to salinity.Ion content of the cell walls, chloroplasts and vacuoles of Panicum leaf cells was investigated during the various stages of osmotic adaptation. An increase in sodium and chloride content of the cell walls during the early period of adaptation probably prevented the full osmotic adaptation of the protoplasts. It is suggested that a locally unbalanced distribution of ions may be one of the reasons for the decrease in growth rate during the process of osmotic adaptation and frequently after that.
X‐ray Microanalysis of Phosphorus in Scenedesmus obtusiusculus
Authors: TILLBERG JAN ERIC , BARNARD TUDOR , ROWLEY JOHN 
Published: April 2006

AbstractResults from energy dispersive x‐ray microanalysis indicate considerable variation in phosphorus as well as in other elements found in polyphosphate granules in cells of Scenedesmus obtusiusculus starved of phosphorus for 24, 36 and 48 h. Comparison is made with cells at a 3‐h stage of synchronization and after 48 h cultivation in a phosphorus‐containing medium. After 48 h with a very limited external source of phosphorus, phosphorus was not detectable in‘polyphosphate granules’ in Epon‐Araldite sections unless the resin and other organic molecules were removed by plasma microincineration. In spite of the low amounts of elements (Mg. Al, Si, P and Ca) detected in these granules they are still dense to electrons in unstained sections, like the granules in cells cultivated in the presence of phosphorus. That suggests that the localized differences in the structural packing of elements or radicals in the polyphosphale polymer is more important For visualization of unstained polyphosphate granules than the absolute concentration of phosphorus or other elements. In contrast to previous assumptions, the abundance of morphologically‐observable‘polyphosphate’ granules can no longer be taken as an index of mobilizable phosphate reserves.
Culture of Shoot Apices of Theobroma cacao
Authors: ORCHARD J. E. , COLLIN H. A. , HARDWICK K. 
Published: April 2006

AbstractSurface sterilized buds of young cocoa plants (Theobroma cacao L.) taken at particular stages of the flush cycle were placed in Linsmaier and Skoog agar medium supplemented with a range of growth regulators. Only buds taken at the 1–2 (dormant) stage of the flush cycle and treated with gibberellic acid (GA3) alone and GA3plus kinetin (KN) supplement showed bud opening. In liquid Linsmaier and Skoog medium buds isolated at the 1–2 stage also responded to GA3 and KN. In this case addition of KN caused bud opening, while GA3 either initiated bud opening only or opening followed by leaf expansion depending on the concentration of GA3 supplied. Bud development was inhibited when ABA was included in the medium hut this was overcome by the presence of GA3 but not KN. Since a hormonal supplement was required for any response from the excised buds, it is suggested that the intermittent growth of the shoot apex in the intact plant may be determined by hormonal stimuli derived from other parts of the plant. The findings also indicate that the bud apices could be maintained in culture for long periods which may provide a basis for the development of a micropropagation procedure for cocoa.
Amylase and Invertase Activities and Carbohydrate Contents in Relation to Physiological Sink in Carnation
Authors: FAWZI A. F. A. , EL‐FOULY MOHAMED M. 
Published: April 2006

AbstractIn carnation, Dianthus caryophyllus L. cv. Hanacy, initiation of flower primordia was followed by mobilization of polysaccharides from leaves to developing flower buds and mature flowers. This process functioned by integrative activities of amylase and invertase, ensuring abundant flow of the mobilized carbohydrates from the source to the sink. Successive stages of floral development exhibited different sink strengths as indicated by amylase and invertase activities and carbohydrate contents in stem apices, which increased with progression of floral development.
Development in vitro of Nephrolepis exaltata cv. Bostoniensis Runner Tissues
Authors: LOESCHER WAYNE H. , ALBRECHT CAROLYN N. 
Published: April 2006

AbstractStudy of organogenesis in vitro in runner tissues of the fern Nephrolepis exaltata cv. Bostoniensis has shown that the process involves two stages: the first being primoirdium initiation and the second involving release of these primordia from an apparent quiescent state. In vitro shoot development from the primordia required light and an exogenous supply of carbohydrate. No exogenous growth regulators were necessary, but rate of shoot development was promoted by both NAA and kinetin. Root initiation occurred in both the light and dark and was promoted by 2,4‐D and NAA, but neither was essential. Organogenesis was generally inhibited with standard levels of Murashige and Skoog inorganic salts, but inhibition could be avoided with the use of dilute levels.
Effect of Light on Deamination and Oxidation of Adenylic Compounds in Cotyledons of Pharbitis nil
Authors: NGUYEN JACQUELINE 
Published: April 2006

AbstractSince labelling of ureides from adenine‐8‐14C is higher in dark than in light, the influence of light on the deamination and the oxidation of adenylic compounds by cotyledon discs of Pharbitis nit was investigated. Among the three possible adenylic precursors for the deaminative step, adenine was found to be the best compound for the study of the deaminative rate, adenosine being easily hydrolyzed into adenine, and AMP undergoing an apparent complete hydrolysis before entering the cells. By analysis of adenine‐8‐14C metabolism for brief periods, it was determined that the rate of deamination of adenylic compounds was faster in light than in dark. In contrast, the activity of xanthine dehydrogenase was much higher in the dark than in light. The level of the activity of uricase was the same in both light and dark.
Tissue and Cell Culture of ‘Passe Crassane’ Pears: Amylase Pattern of Cultured Tissues Compared with Whole Fruit
Authors: PECH JEAN‐CLAUDE , LATCHÉ ALAIN , FALLOT JEAN 
Published: April 2006

AbstractCalluses and cell suspension cultures were initiated from young and fully developed fruits and from stem and petiole tissues of ‘Passe Crassane’ pears. On a dry weight basis, proliferation is significantly higher in tissues from full‐grown fruits and petioles. Cullus tissues grown in vitro have a protein content up to 25 times higher than the initial quiescent organ. Three amylase fractions (2 β amylases E, and E2: 1 α amylase E3) were isolated by gel filtration on Sephadcx G‐100 and isoenzymes revealed in these fractions after polyacrylamide gel electrophoresis.Comparison of amylase activity in actively growing cells and in auxin‐starved cell suspensions shows that β‐amylase activity is mainly a function of cell growth, while α‐amylase activity is more related to the age of the cells.The presence of two isoenzymes in the β‐amylase E2 fraction was found to be highly characteristic of young fruits. The same polymorphism was found in all the strain of tissues thus indicating that tissues grown in vitro retain or revert to a juvenile biochemistry. The growth hormone. 2,4‐dichlorophenoxyacetic acid, used to support cell division, is demonstrated to be responsible for the reversion of the β‐amylase polymorphism from a mature to a juvenile phenotype in mature fruit explants incubated in vitro.The interest of fruit tissue and cell culture for the study of fruit physiology is questioned and discussed.
Environmental control of turion formation in curly pondweed (Potamogeton crispus)
Authors: SASTROUTOMO SOETIKNO S. 
Published: April 2006

AbstractThe turions of Potamogeton crispus L. develop in early summer and function in propagation and dispersal. Under natural conditions during longday periods, an average minimum air temperature of more than 12°C was found to be important for turion formation. Experiments with controlled environments indicate that both temperature and photoperiod regulate turion formation. Turions can be induced at 13°C or above but not at 8 or 10°C. At a temperature range of 13–24°C turions form in both 12‐ and 16‐h days, but not in 8‐h days. By increasing temperature from 24 to 30 or 35°C turions can be induced under 8‐h days. Light intensity was found to be important in the formation of turions.
Formation of aerenchyma in roots of Zea mays in aerated solutions, and its relation to nutrient supply
Authors: KONINGS HENDRIK , VERSCHUREN GER 
Published: April 2006

AbstractThe formation of lysigenous cavities (aerenchyma) in the root cortex of maize, Zea mays L. cv. Capella, under well‐aerated conditions has been studied in relation to the composition of the nutrient solutions. Nitrogen, either supplied as nitrate or as ammonium, reduced the cavity formation by the roots. This reduction was most apparent at nitrate concentrations above 2 mM. Cavities were increasingly formed when the nitrate concentration was decreased and they reached their largest dimensions in roots growing in water. Thus, inadequate availability of nitrogen leads, under acrated conditions, to deterioration of cortex cells and cavity formation in the maize roots. It is suggested that cavity formation in these roots is connected with reduced nitrogen assimilation.
Effect of morphactin on certain plant growth substances in bean roots
Authors: PARUPS E. V. 
Published: April 2006

AbstractThe effect of morphactin (methyl‐2‐chloro‐9‐hydroxyfluorene‐9‐carboxylate) on the content of several plant growth substances in bean roots was determined. Beans (Phaseolus vulgaris L. cv. Spartan) were soaked in aqueous solutions of morphactin, 1 x 10‐4, 1 x 10‐5, and 1 x 10‐6M and grown in moist vermiculite. As controls were used beans grown in water‐moistened vermiculite either intact or having the root tips removed (decapped). The roots, morphactin‐treated, controls, and the decapped ones were analyzed for indol‐3‐yl acetic acid (IAA), indol‐3‐yl acrylic acid (IAcA), indol‐3‐yl pyruvic acid (IPyA), indol‐3‐yl lactic acid (1LA), abscisic acid (ABA), gibberellins GA1, GA3, GA4, and GA9 using gas‐liquid chromatographic methods. Morphactin, while affecting the geotropical responses, changed also the growth substance content of roots. IAA, ABA, GA1, and GA9 contents decreased, IPyA, IAeA, GA3, and GA4 contents were not affected and ILA content increased slightly with increasing dosages of morphactin. Growth substance pattern of decapped roots resembled that of the roots treated with the highest dose, 1 x 10‐4M, of morphactin.
Phenylalanine ammonia‐lyase activity in callus cultures of Pinus elliotii
Authors: LAU YIU‐LAM , SCHELD HERBERT W. , COWLES JOE R. 
Published: April 2006

AbstractPhenylalanine ammonia‐lyase (PAL) activity increased 8‐ to 12‐fold in pine (Pinus elliotii Engelm.) callus tissue within 2 days after subculturing on fresh medium. Factors such as increasing the sucrose content of the media, imposing additional tissue in jury or subculturing more frequently did not cause additional stimulation of PAL activity. The rapid increase in PAL activity appeared to be due to enzyme activation, since cycloheximide did not appreciably reduce the stimulation of PAL activity. The subsequent loss of increased PAL activity with age was reduced by cycloheximide and a cool growth environment.
Changes in phenolic acids and abscisic acid in sugar pine embryos and megagametophytes during stratification
Authors: Murphy J. Brad , Noland Thomas L. 
Published: April 2006

The phenolic acids and abscisic acid (ABA) of sugar pine (Pinus lambertiana Dougl.) embryos and megagametophytes, separated by high‐pressure liquid chromatography, were analyzed during 90 days stratification of the seeds. The phenolic acids occurred mainly as glycosides. Following hydrolysis, the majority of phenolics present could be identified as common benzoic and ciranamic acid derivatives. Levels of phenolic acids were relatively low in dormant seeds, but increased substantially in the embryos during stratification at 5°C, particularly cinnamic acid, p‐coumaric acid, ferulic acid, and one unknown. This active synthesis during stratification did not support an inhibitory function for phenolic acids. During stratification at 5°C, changes in ABA levels in both tissues followed a triphasic pattern, with no loss during the first 30 days, a significant decrease the second 30 days, and a lesser decrease the last 30 days. Loss of ABA from moist seeds at 25°C occurred three times as rapidly, so that by 30 days the ABA level of these seeds was equivalent to that of seeds stratified 90 days at 5°C; however, dormancy was not alleviated at 25°C. Application of exogenous ABA (10−7 to 10−4M) to stratified seeds did not significantly reduce germination. Together, the above results did not support a primary role for ABA in the maintenance of dormancy in sugar pines.A correlated increase in phenylpropanoid metabolism and respiratory capacity with increased germinability during stratification suggests that loss of dormancy may be more closely dependent on increased levels of growth promoters or shifts in metabolic pathways.
The Effects of Different Cotton Varieties on the Carmine Spider Mite, Tetranychus cinnabarinus Boisd. (Acari: Tetranychidae)
Authors: ŞEngonca Ç. , Lababidi M. S. , Gerlach S. 
Published: April 2006

AbstractThe aim of this study was to delta differences in resistance to the carmine spider mite, Tetranychus cinnabarinus between cotton varieties grown in different areas. The effects of 8 varieties from several countries cm the development, longevity and fecundity of T‐cinnabarinus were investigated in the laboratory. On leaves of the Egyptian cotton, Gossypium vitifolium, variety Giza 75, both females and males required a longer period to complete development than on the G. hirsutum varieties Coker 310 and MCH H. Female mites reared on the variety Coker 310 lived significantly longer and had the longest oviposition period. The largest total progeny per female was observed on the varieties Coker 310 and MCH H, the smallest on the varieties Aleppo 1 and Giza 75. The cotton varieties had no effect on the sex ratio of T. cinnabarinus. In general, the G. hirsutum varieties Coker 310 and MCH 11 appeared to be most supportive for T. cinnabarinus, whereas the G. vitifolium variety Giza 75 clearly showed reduced susceptibility.
Different Behavior of Brassica juncea and B. carinata as Sources of Phoma lingam Resistance in Experiments of Interspecific Transfer to B. napus
Authors: Dolores Sacristan Maria , Gerdemann Maria 
Published: April 2006

AbstractWith the aim to transfer Phoma lingam resistance into rape, successful interspecific crosses were made between three oilseed rape varieties (Brassica napus) and the resistant species B. carinata and B. carinata. Although both hybrid types B. napus×B. juncea and B. napus×B. carinata showed the same high level of resistance as the respective resistant parent, the resistance could be only transferred from juncea crosses. After three backcross generations, lines morphologically undistinguishable from rape, fertile, and with a high degree of resistance were obtained. The resistance of B. carinata was practically lost in the first backcross. A possible explanation of this different behavior could be a higher recombination between the genomes B and C (juncea crosses) than between B and A (carinata crosses). The: applied embryo culture increased the yield of hybrids and first backcross plants and reduced considerably the generation time.
Variation in Nicotine Content of Cultured Cell Lines of Nicotiana Species and their Somatic and Sexual Hybrids
Authors: Sabour M. , Simmonds J. , Setterfield G. 
Published: April 2006

AbstractSeveral Nicotiana species, their intergeneric sexual and somatic hybrids were compared for their in vitro growth rate and nicotine content. Cell yield on a dry weight basis and HPLC analysis of their nicotine content revealed a very high variation within each cell line from parental, sexual and somatic hybrids for the two traits analyzed. The trigeneríc sexual hybrids (N. rustica × N. debneyi) × N. tabacum and only two of the N. rustica × N. tabacum somatic hybrid lines show a positive heterosis in nicotine content in vitro The in vitro growth rate and nicotine content did not demonstrate a statistically significant correlation.
Evidence for Monotelodisomics in Rye (Secale cereale L.)
Authors: Melz G. , Winkel A. 
Published: April 2006

AbstractMonotelodisomics of chromosome arms 2RL and 6RL were observed in progenies of rye trisomics. The monotelodisomic of chromosome arm 6RL (2n = 13 + 6RL) is vital and is well transmitted through the pollen. In the progeny of monotelodisomic 2RL. (2n = 13 + 2RL) no monotelodisomic but one monotelotrisomic of chromosome arm 2RS (2n = 14 + 2RS), one trisomic with an aberrant chromosome consisting (if chromosome arm IRS and a part of chromosome arm 2RL (2n = 14 + 2RSL) and one double telotrisomic of chromosome 2R (2n = 13 + 2RS + 2RL) have been identified.
Variation of Telomeric Heterochromatin Among Inbred Lines in Diploid Rye (Secale cereale L.)
Authors: Pilch J. , Hesemann C. U. 
Published: April 2006

AbstractThe amount of Telomeric C‐heterochromatin was investigated in 20 inbred lines of rye and their open‐pollinated source cultivars. In this short communication only the banding pattern of the chromosomes in the lines is presented. The inbred lines had an amount of heterochromatin similar to the source cultivars. Both groups carried some chromosomes with small telomeric C‐bands. The individual source cultivars were composed of 2—4 karyotypes having different amounts of telomeric heterochromatin. Most karyotypes were also identified in the respective inbred lines. Results suggest that the in breed in i: process was not related to a reduction of telomeric C‐hetrerochromatin in rye chromosomes.
Salt Tolerance of an Amphiploid between Triticum aestivum and Agropyron junceum
Authors: Forster B. P. , Gorham J. , Miller T. E. 
Published: April 2006

AbstractThe main objective of this work is to demonstrate the expression of salt tolerance genes in a wheat‐Agropyron amphiploid. Salt tolerance tests were carried out on wheat varieties, ‘Chinese Spring,’ and ‘Glenn‐son 81’ the amphiploid between ‘Chinese Spring’ and A. junceum, A. junceum and amphiploid × wheat hybrids, Apart from germination in petridishes all other tests were carried out on plants grown in saline hydroculture tanks. Fresh weight measurements are given for stressed and non‐stressed plants as well as measurements of harvest ripe plants. The utility of A. junceum as a source of salt tolerance genes for wheat is discussed.
Trait Associations in Introgressed Populations of Pearl Millet
Authors: Bramel‐Cox P. J. , Andrews D. J. , Frey K. J. 
Published: April 2006

AbstractPrincipal component analysis has been used in this study to describe the associations among 17 traits measured on progenies developed from matings of two adapted pearl millet inbreds with three exotic pearl millets. The exotic parents were a primitive I and race, a weedy relative, and a wild relative. The first three components were calculated for these matings and the associations defined. Correlations between these components and grain yield and growth rate were also determined. The first principal component described a hybrid index in five of the six matings, and a number of other complexes of traits were determined by this component or the other two. Some were common to several matings. The first three components accounted for only 50–60% of the total variability; thus no strong association of trans was found that would hinder recombination of parental types to select agronomically desirable segregates with high grain yield or growth rate.