bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Roles of the Cotyledons and Auxin in the Adventitious Root Formation of Hypocotyl Cuttings of Light‐Grown Cucumber Seedlings
Authors: Katsumi Masayuki , Chiba Yoshiko , Fukuvama Machi 
Published: April 2006

AbstractAdventitious root formation in encumber hypocotyl cuttings was studied. Root formation was quantitatively related to the amount of the cotyledons attached to the hypocotyl. Complete removal of the cotyledons diminished root formation entirely. Hut the removal of the apical bud had no effect. Treatment of the hypocotyl with triiodobenzoic acid resulted in the inhibition of root formation. On t he other hand, IAA promoted root formation. Promoting concentration of IAA was 1 mg/1 for the cuttings with intact cotyledons and 10 mg/1 for those with l/8th of the cotyledons. The first two or three days of treatment was most effective. The presence of auxin (IAA‐like. substance) in cucumber seedlings was demonstrated by paper chromatography and the pea straight test. It is concluded that the cotyledon is necessary for root formation in cucumber hypocotyl cuttings and that auxin is at least one of the factors supplied from the cotyledons.
Interaction of Growth Retardants and Temperature in Growth, Flowering, Regeneration, and Auxin Activity of Begonia × cheimantha Everett
Authors: Heide Ola M. 
Published: April 2006

AbstractSoil application of CCC reduced stem and leaf growth in Begonia plants. This effect was evident with all concentrations tested at 18°C, whereas at 21 and 24°C no growth–retarding effect was observed with 2 × 10−2 M CCC, and with 5 × 10−3 M growth was even stimulated. Flowering was promoted by CCC in long day and neur–critical temperature, particularly under low light intensity in the winter. The formation of adventitious buds in leaves of plants grown at 21 and 24°C was stimulated when the plants received 5 × 10−2 and 2 × 10−2 M CCC, while 8 7times; 10−2 M was inhibitory. In plants grown at 18°C bud formation was inhibited by all CCC concentrations. Root formation in the the leaves was usually stimulated by high CCC concentrations, while root elongation was reduced. The level of ether–extractable. acidic auxin (presumably IAA) in the leaves was lowered by CCC treatment of the plants, hut this required higher CCC concentrations at higt than at low temperature.When applied to detached leaves CCC stimulated bud formation at concentrations ranging from 10−4 to 10−2 M in leaves planted at 18 and 21°C. At 24°C budding was inhibited by 10−2 M CCC, the lower concentrations being stimulatory also at this temperature. Root formation and growth were not much affected by CCC treatment of the leaves, but increased with the temperature.Soil application of Phosfon (4 × 10−4 M) had no effect on growth and flowering, nov did it affect the subsequent regeneration of buds and roots in the leaves. In detached leaves Phosfon stimulated bud formation with au optimum at 10−6 M. Root formation was stimulated by Phosfon at all temperatures, the optimal concentration being 10−5 M, whereas root length was conversely affected. Foliar application of B‐995 to intact plants and treatment of detached leaves greatly inhibited the formation of buds and had little effect on root formation. B‐99D reduced the growth and delayed flowering in the plants.
Phytochrome Controlled RNA Changes in Terminal Buds of Dark Grown Peas (Pisum sativum cv. Alaska)
Authors: Jaffe M. J. 
Published: April 2006

AbstractThe terminal buds of intact dark grown Alaska pea plants (Pisum sativum) respond to low intensity red light by an enhanced rate of expansion of their leaflets. Twenty four hours after irradiation, red light was found to have increased the ribosomal fraction of the RNA content of the terminal buds. The increase in total RNA liter did not occur if the red light was immediately followed by irradiance with low intensity far red light.
Ribonuclease and Chlorophyllase Activities in Senescing Leaves
Authors: Phillips D. R. , Horton R. F. , Fletcher R. A. 
Published: April 2006

AbstractThe activities of two enzymes, ribonuclease and chlorophyllase were investigated during the senescence of leaves. Ribonuclease activities were measured in primary leaves of Phaseolus vulgaris, and related to the levels of nucleic acid, protein and chlorophyll. Similarly, changes in chlorophyllase activity during senescence of leaves of Raphanus sativus were measured and related to chlorophyll. During senescence the levels of each enzyme as well as its respective substrate declined. Retardation of senescence, by excision of young tissue from intact plants or by treatment of detached leaves with cytokinins resulted in a maintainace of both the substrate and enzyme levels. It was concluded that high levels of ribonuclease and chlorophyllase activity are not linked directly with the degradation of RNA and chlorophyll during leaf senescence.
Ethylene Production from Pardee's CO2 Buffers
Authors: Forsyth F. R. , Eaves C. A. 
Published: April 2006

AbstractFifteen milliliters of Pardee's CO2 buffer containing diethanolamine, thionrea, potassium bicarbonate and 6 N hydrochloric acid produces up to 108 μg of ethylene during a 42 hour period. Only 1/25 as much ethylene is produced from monoethanolamine and still less from triethanolamine. All components of the buffer with the exception of hydrochloric acid are necessary for maximum ethylene production. Increasing the level of hydrochloric acid depresses ethylene production.
The Effect of Methyl Glyoxal on Growth and Cell Division of Chlamydomonas reinhardii
Authors: Morris Ian 
Published: April 2006

AbstractMethyl glyoxal, at concentrations of 1.0–2.0 mM, inhibits growth of the green alga, Chlamydomonas reinhardii. The photosynthetic assimilation of carbon dioxide is also inhibited by the glyoxal. At the lower concentrations (less than 1.0–1.5 mM) protein synthesis Is inhibited, whereas polysaccharide synthesis and assimilation of carbon dioxide into the alcohol–soluble fraction is stimulated; at higher concentrations fl.5–2.5 mM) these latter two processes are also inhibited. Cell division in synchonized cultures of the alga is more sensitive to methyl glyoxal when it is added at the start of the growth cycle than when added late in the growth cycle. However, when added late in the growth cycle, methyl glyoxal delays the onset of cell division by 2 hours. No such delay occurs when cycloheximide is added 4–6 hours before division.
Stimulation of Growth of Two Marine Green Algae by Organic Substances Excreted by Enteromorpha linza in Unialgal and Axenic Cultures
Authors: Berglund Hans 
Published: April 2006

AbstractThe alga Enteromorpha linza was cultivated in the artificial medium ASP 6F. Substances leaking out from the alga into the medium were extracted by ether and shown to stimulate the growth of two green algae. The amount of extract obtained was very small. One part was watersoluble, and the other part emulsive only in sodium hydroxide.
Studies on Cassava, Manihot utilissima. II. Biosynthesis of Asparagine‐14C from 14C‐labelled Hydrogen Cyanide and its Relations with Cyanogenesis
Authors: Nartey Frederick 
Published: April 2006

AbstractSeeds and seedlings of Manihot utilissima were analysed for cyanogenic glycosides und free amino acids, with special reference to valine and isoleucine which serve as precursors of the aglycone moieties of linamarin and lotaustralin. Seeds contained traces of valine and isoleucine but no glycosides, whereas seedlings contained high concentrations of these amino acids and glycosides. Illumination of seedlings led to a steep increase in the concentration of glycosides followed by a decrease without excretion of detectable HCN. Seeds accumulated asparagine, while seedlings accumulated both asparagine and glutamine in the storage and transport of nitrogen. Seedlings incorporated 13.2 per cent of label from valine‐14C(U) and 2.4 per cent of label from isoleucine‐14C(U)into linamarin and lotaustralin, respectively. In both cases, appreciable amounts of label were also incorporated into asparagine. 49 per cent of label from H14CN was incorporated inio asparagine in which ca. 98 per cent of total radioactivity was located in the amide‐carbon atom. The different patterns of labelling which occurred during the assimilation of H14CN and 14CO2 showed that cyanide metabolism did not proceed via CO2, and that M. utilissima contains an efficient enzyme‐system which catalyses the conversion on high concentrations of HCN into asparagine, which subsequently enters different metabolic pools involved with respiration, protein and carbohydrate syntheses. Cyanogenesis in M. utilissima appears lo be directly influenced by available pools of valine and isoleucine, and the metabolism of HCN released from linamarin and lotaustralin by the action of linamarase may be directly related to respiratory and synthetic processes by way of the incorporation of HCN as a unit into asparagine.
The Auxinic Activity of Thioglycollic Acid Derivatives of β‐Di‐ketones
Authors: Barrett D. W. A. , George E. F. 
Published: April 2006

Abstract2,2′‐Di(carboxymethylthio) pentan ‐4‐one was found to increase the stem height of intact tomato plants growing in pots under glass. Stem height was increased by 60 percent although this was accompanied by malformations in lamina development, leaf epinasty, and a final reduction in shoot weight. Stem growth of tobacco and potato were also stimulated by this compound but the deleterious effects on leaf development were less marked. Subsequent screening of chemical analogues, using as an assay the growth response of intact tomato plants revealed that 3,3′‐di(carboxymethylthio)heptan‐5‐one initially stimulated stem growth but then produced severe shoot damage, similar to that caused by phenoxyacetic acid herbicides. Both chemicals stimulated extension growth in a wheat coleoptile section test though to a lesser extent than indole‐3‐acetic acid.Like the carboxymethyl‐N:N‐dialkyldithiocarbamates, these straight chain compounds appear to possess true auxin activity that could be related to the formation of an incomplete unsaturated “ring” system.
Effect of Various Light Treatments on Chlorophyll Formation in Excised Potato Roots
Authors: Bajaj Y. P. S. , McAllan J. W. 
Published: April 2006

AbstractPotato root tips were grown in cultures and the effect of blue, red, and white light on chlorophyll formation was studied. The roots grown in white light turned green in 4–6 weeks, whereas in blue or red light, green colour occasionally appeared at places. The chlorophyll contents, as determined by the spectrophotometeric method, were found to be maximum in unfiltered light followed by blue and red light. In white and blue light treatments chlorophyll a contents were higher than chlorophyll b, however in red light this was reversed. The results are compared with earlier experiments on chlorophyll formation in excised roots.
Gibberellin and Protease Activity in Medicago sativa
Authors: Cohen Bat‐Sheba , Leshem Y. , Pinsky A. 
Published: April 2006

AbstractDuring germination of the lucerne seed, proteolytic and gibberellinic activity increases. Exogenous GA added to the solution in which the seed was germinated caused an increment in proteolytic activity. CCC inhibited the biosynthesis of GA in the seed‐ ling, and had no effect on the proteases. This indicates that there are other factors Hum GA responsible for the increment in proteolytic activity during Medicago germination.
Palmelloid Formation of Chlamydomonas II. Mechanism of Palmelloid Formation by Organic Acids
Authors: Iwasa Kozo , Murakami Shohachi 
Published: April 2006

AbstractTo clarify the mechanism of palmelloid formation by organic acids, the dissociation of the suspension of palmelloids in different media was studied. It was found that the palmelloids can be dissociated by the calcium ion at the low concentration of 6.8 × 10‐5M, but not by the magnesium ion. The dissociation is suppressed by the phosphate ion. Furthermore, Chlamydomonas cells grown in media containing EDTA or GEDTA or in media deficient in calcium, are induced to form palmelloids. These results indicate that the effect of organic acids on the formation of palmelloids are due to their ability to chelate with calcium.
The Activity of α‐Amylase in the Shoot and its Relation to Gibberellin‐induced Elongation
Authors: Katsumi Masayuki , Fukuhara Masako 
Published: April 2006

AbstractThe activity of α‐analyses in various plant organs was examined and the relation‐ ship between the enzyme activity and the leaf sheath elongation of dwarf mutants of maize was investigated.It has been shown that α‐amylase exists in various plant organs. Especially high activity was detected in the bean hypocotyl. The regional activity of a‐amylase in the epicotyl of the pea and the hypocotyl of the morning glory was examined. Higher activity was observed in the regions closer to the cotyledons. In the first leaf sheath of d5 mutants of maize, GA3‐treatment resulted in the promotion of α‐amylase activity, and there was a parallelism between GA3‐induced elongation and α‐amylase activity. Removal of the endosperm from seedlings did not influence the GA3‐indnced elongation of the leaf sheath or the promotion of α‐amylase activity. From these results it is concluded that at least some of the α‐amylase is actually formed in the leaf sheath, and that there exists a distinct parallelism between the GA3‐induced promotion of enzyme activity and leaf sheath elongation.
Adaptations of the Photosynthetic Mechanism of Sugar Maple (Acer saccharum) Seedlings Grown in Various Light Intensities
Authors: Logan K. T. , Krotkov G. 
Published: April 2006

AbstractSugar maple (Acer saccharum Marsh.) seedlings were grown in a nursery for three years in 13, 25, 45 and 100 per cent of full daylight. During the third year of growth, the rates of their apparent photosynthesis and respiration were measured periodically with an infra‐red gas analyzer at various light intensities and normal CO2 concentration. In addition, the rates of apparent photosynthesis of a single attached leaf of the same seedlings were measured at saturating light intensity, hut varying CO2 concentrations.An increase in the light intensity in which seedlings were grown had no effect on their height or mean leaf area, hut resulted in thicker leaves, an increase in the total leaf area per seedling due to an increase in the number of leaves, an increase in the dry weight especially of roots and a decrease in the chlorophyll content of leaves.Throughout the growing season seedlings grown in full daylight, as compared with those grown in lower light intensities, had the lowest rates of apparent photosynthesis measured at standard conditions (21,600 lux light intensity and 300 ul/l of CO2), when this was expressed per unit leaf area, hut the highest rates on a per seedling basis. Thus dry matter production attained at the end of the growing season correlated positively with the photosynthetic rate per seedling, but not per unit leaf area. The rates of apparent photosynthesis of seedlings grown at lower light intensities were more responsive to changes in light intensity or CO2 concentration than those of seedlings grown in full daylight intensity.
Studies on the Activity of Beta‐Analyses of the Chloroplasts of Stellaria media during Prolonged Illumination
Authors: Haapala Heikki 
Published: April 2006

AbstractThe changes in the activity of enzymes hydrolyzing starch were studied. Enzymes were extracted from the leaves of Stellaria media. Enzyme activity seems to be concentrated in the chloroplasts. Beta‐amylase has been identified as the main enzyme hydrolyzing starch in these leaves.When Stellaria media plants are left in continuous illumination after a normal light‐dark‐rhythm), beta‐amylase activity remains essentially unchanged for some time. Alter an Illumination of 24–27 hours the activity suddenly increases. This phenomenon occurs at about the same time as the rapid disintegration of starch previously accumulated in the chloroplasts. In the light of present‐day knowledge the increase in the activity cannot be explained.
Studies on Deoxyribonucleotide Synthesis in Vicia faba
Authors: Odmark Göran 
Published: April 2006

AbstractThe incorporation of uniformly labelled [14C] cytidine into the nucleic acids was studied in root tips of Vicia faba. Cytidine was found to be incorporated into RNA and DNA and the specific activities of the individual mononucleotides were deter‐ mined. The pyrimidine nucleotides were degrade and the ratio between the specific activity of the pentose and the specific activity of the base was determined for each nucleotide.CMP of RNA and deoxy CMP of DNA bad almost the same pentose: base ratios as The cytidine added to the incubation medium. It was concluded that the administered cytidine or a derivative of it was reduced to the corresponding deoxycytidine compound without breakage of the bond between pentose and base.[14C)‐cytidine was transformed to UMP of RNA with some loss of radioactivity from the pentose and had almost the same pentose: base ratio as deoxy TMP of DNA. This indicates that the formation of thymidine phosphates involved The reduction of a uridine compound.Furthermore the incorporation of 14C‐labelled thymidine, deoxyadenosine and deoxyguanosine into DNA was studied. Deoxyguanosine was found to be incorporated only to a slight extent. This finding has been discussed in relation to previous results.
Characterization of Boron Deficiency in Soybeans
Authors: Brown J. C. , Ambler J. E. 
Published: April 2006

AbstractBoron‐deficient soybean roots have a rosette appearance at the terminals caused by the death of the root primordium and the initiation of new root primordia. The root tips show some darkening, swelling, and then a collapse of the tissue. The petiole s of B‐deficient plants are very brittle.Physiologically, B‐deficiency in HA‐soybeans does not appear to involve an interference in the transport of photosynthate (C14 distribution) or precursors required for citrate synthesis in the roots.More Ca 45 was found in the tops of B‐sufficient than B‐deficient plants, but the opposite trend existed in the root sap. Boron deficiency symptoms were accentuated by maintaining a relatively low pH of the prenutrient solution by the addition of K salts.
14C‐Studies on Apple Trees. IV. Photosynthate Consumption in Fruits in Relation to the Leaf‐Fruit Ratio and to the Leaf‐Fruit Position
Authors: Hansen Poul 
Published: April 2006

AbstractThe photosynthate consumption in apple fruits in relation to the leaf/fruit ratio was studied in sections of branches of the Graasten and Golden Delicious varieties by exposure to 14CO2during July and August. A significant, negative correlation was found between the fixation of 14C in the fruits in terms of percent of the total amount of 14C absorbed and the leaf/fruit ratio of the branch sections. The leaf area required for the saturation of one fruit was found to be ca. 190 and 230 cm2 (14 and 17 leaves) in the case of Golden Delicious, and ca. 400 and 670 cm2 (25 and 42 leaves) for Graasten in July and August, respectively, calculated under conditions of large leaf areas per fruit. In such cases a fairly good, reverse proportionality exists between the 14C fixation in the fruit in terms of percent and the leaf area expressed in multiples of saturation area. At low leaf/fruit ratios, however, the actual saturation area is found to be lower than the theoretically computed one.The translocation of the 14C assimilated in the leaves of the extension shoots or of spurs without fruits to fruits on other spurs was on the whole promoted by a decreasing leaf/fruit ratio in the parts in question; similarly the greatest transport took place on the side where the leaf/fruit ratio was lowest. The fixation was often greatest in the fruit closest to the treated leaves, hut in a number of cases the value was higher for the second closest or even further removed fruits. In this connection the importance of the size of the fruit and the vascular connections is discussed.
Effect of Auxins and Light on Rooting Stem Cuttings of Populus nigra Salix tetrasperma, Ipomea fistulosa and Hibiscus notodus in Relation to Polarity
Authors: Nanda K. K. , Purohit A. N. , Kochhar V. K. 
Published: April 2006

AbstractThe apical and basal ends of stem cuttings of Populus nigra, Salix tetrasperma, Ipomoea fistulosa and Hibiscus notodus were treated with 10 mg/l solutions of IAA and IBA for 24 hours and were planted either erect or inverted both in light and dark. Observations for the number of cuttings that rooted and the roots produced on them were recorded at weekly intervals. In Salix, Ipomoea and Hibiscus rooting was more on cuttings planted erect, while in populus it did not differ much with the manner of planting. The reduced rooting in inverted cuttings may be ascribed to the low level of endogenous auxin at the apex due to polar transport. An exogenous application of auxins enhanced rooting on inverted cuttings. In dark, roots on Populus and Salix cuttings were produced both above and within the rooting medium. The weak polarity of these two plants may be due to the potential root primordia reported in their stem. The formation of callus occurred on the top of Populus cuttings whether planted erect or inverted but it differentiated into branches on erect cuttings only. In those planted in an inverted position the callus failed to differentiate in spite of the application of kinetin, auxins, TIBA, coumarin and sucrose, and dried ultimately.
Growth and Endogenous Gibberellin Content of Dormant Groundnut Embryonic‐axes as Influenced by Leaching and GA3
Authors: Sreeramulu N. , Rao I. M. 
Published: April 2006

AbstractLeacthing the excised embryonic‐axes from dormant groundunt (Arachis hypogaea) seeds resulted in their growth. However, their growth was stunted compared to that of after‐ripened ones. It is attributed to (1) the lower amount of gibberellin‐like substances in the dry, dormant embryonic‐axes than in the after‐ripened ones, and (2) the inability of the former to sythesise tbe tibberetllin as indicated by the lower content compared to the after‐ripened ones kept in water. Exogenousty supplied GA3 (0.1 mg/1) increased both the endogenous gibberellin and growth of the dormant, leached embryonic‐axes to the level of after‐ripened ones.
Influence of the Maize Dwarf Mosaic Virns and Simazine upon the Buffer Soluble Proteins and Catalase Activity of a Virus‐susceptible and a Virus‐tolerant Variety of Zea mays
Authors: Millikan D. F. , Mann Don R. 
Published: April 2006

AbstractInbred corn varieties differing in their tolerance to the maize dwarf mosaic virus infection also differ in varietal character and host response to simazine. Oh 7B, a tolerant cv., has less total soluble and globulin proteins than the sensitive variety, H 55, but more Kjeldahl nitrogen, albumin protein and a doubling of catalase activity. Virus inoculation in Oh 7B causes a reduction in all three protein fractions, Kjeldahl nitrogen and catalase activity. Deleterious virus‐simazine interaction does not occur with either variety and the observed varietal and host response differences in protein may account for the conflicting reports of other workers.