bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Soil Water Regimes on Leaf Water Potential, Growth and Development of Soybeans
Authors: ADJE‐TWUM DANIEL C. , SPLITTSTOESSER WALTER E. 
Published: April 2006

AbstractThe growth and development of soybeans (Glycine max L. cv. Amsoy) was studied at soil matric potentials of −0.1 to −1.0 bars. Chlorophyll, photosynthesis, and leaf nitrogen per plant was greatest at −4 bars leaf water potential. Leaf area, number of internodes, plant height and dry weight of vegetative parts declined as leaf water potential decreased from −2 to −19 bars. Nitrogen content and nitrate reductase activity per g fresh weight determined the percentage protein of individual seeds but nitrogen content and nitrate reductase activity per plant determined the amount of total seed protein. The protein synthesized in the seed changed little in amino acid composition with changes in leaf water potential. Leaf water potentials above or below −4 bars decreased yield, total protein and total lipid but plants produced the largest percentage of individual seed protein at −19 bars leaf water potential.
Ferredoxin–NADP+ Reductase from Tsuga canadensis. A Procedure for Isolation and Properties
Authors: RIOV JOSEPH , BROWN GREGORY 
Published: April 2006

AbstractActivity of ferredoxin‐NADP+ reductase in leaf extracts of eastern hemlock [Tsuga canadensis (L.) Carr.] was relatively low, but could be markedly increased by use of protective agents. The best method employed polyvinylpolypyrrolidone (PVP) in the extraction medium plus removal of phenolic compounds by filtering the extracts through an insoluble PVP (Polyclar AT) column. Further purification of the enzyme was achieved by means of DEAE cellulose chromatography and DEAE Sephadex chromatography. A 94‐fold purification of the enzyme with a total recovery of 43% was obtained.The eastern hemlock ferredoxin‐NADP+ reductase was characterized by its diaphorase activity, i.e. the transfer of electrons from NADPH to an electron acceptor. 2,6‐dichlorophenol indophenol. The pH optimum for the oxidation of NADPH is between 8.5 and 9.0. The enzyme is highly specific for its electron donor. NADPH, but shows low specificity for electron acceptors. The apparent Michaelis constant values of the enzyme for NADPH. NADH, and 2,6‐dichlorophenol indophenol are 2.4 × 10−5, 5.4 × 10−3, and 4.7 × 10−5M respectively. The molecular weight of the enzyme, as estimated by gel filtration, is about 45,000. The enzyme is inhibited by both organic and inorganic mercurials and certain cations. Comparison of properties of eastern hemlock ferredoxin‐NADP+ reductase and spinach ferredoxin‐NADP+ reductase shows that both enzymes are similar.
Effects of Cadmium on Respiration Rate and Activities of Several Enzymes in Soybean Seedlings
Authors: LEE K. C. , CUNNINGHAM B. A. , PAULSEN G. M. , LIANG G. H. , MOORE R. B. 
Published: April 2006

AbstractSoybean (Glycine max L. ev. Columbus) seedlings grown in culture solution were treated with cadmium as CdSO4. Final concentrations of cadmium (Cd2+) in the solution were 0, 0.45, 0.90, and 1.35 μM. Soybean leaves, analyzed 10 days after Cd2+ was added to the culture solution, showed increased respiration rate and activities of malate dehydrogenase, acid phosphatase, ribonuclease, deoxyribonuclease, and peroxidase but decreased activity of carbonic anhydrase. Increased activity of hydrolytic enzymes and peroxidase reflects a general senescence response while the carbonic anhydrase decrease is consistent with an antagonism between cadmium and endogenous zinc. Chlorosis, epinasty, abscission of leaves, and decreased growth rate occurred in seedlings treated with 1.35 μM Cd2+.
Effects of Nitrogen, Sucrose, IAA and Kinetin on Explants of Beta vulgaris Grown in vitro
Authors: WELANDER TORKEL 
Published: April 2006

AbstractHypocotyl explants of Beta vulgaris L. were grown on defined agar media with different combinations of IAA and kinetin at varying concentrations of nitrogen or sucrose. The cultures were kept in light (18 h a day) at 27°C for 5 weeks. Root initiation and callus growth were recorded and the callus tissue was analysed for N and K.Root formation was found to increase with increasing nitrogen concentration (from 5 mM to 23.3 mM) in the medium at 10.0 mg/1 of IAA, whereas no stimulation was found at 0.1 mg/1 of IAA. When raising the sucrose level from 20 g/1 to 100 mg/1 at 10.0 mg/1 of IAA and 1.0 mg/1 of kinetin, root initiation was also stimulated. At a lower kinetin and auxin level, however, no increase was recorded.Callus growth was affected by changes in the nitrogen or sucrose concentration of the culture media. The nitrogen content of the callus tissue increased with rising nitrogen concentration of the media. When raising the sucrose level instead of the nitrogen level, the nitrogen content of the tissue decreased.
Temperature and Humidity Effects on Net Photosynthesis and Transpiration of Citrus
Authors: KHAIRI MOHAMED M. A. , HALL ANTHONY E. 
Published: April 2006

AbstractMaximum rates of net photosynthesis for Citrus sinensis (L.) Osbeck and Citrus paradisi Macf. cultivars were observed at the lowest temperature (22°C) under which these subtropical species were examined. Net photosynthesis decreased with higher temperatures or greater vapor pressure differences between leaf and air. The reduction in net photosynthesis due to higher temperatures was associated with reductions in mesophyll conductance to CO2; whereas, the effects of greater vapor pressure differences on net photosynthesis were associated with changes in total leaf conductance to water vapor. Actual water‐use efficiency was reduced at higher temperatures and greater vapor pressure differences, but intrinsic water‐use efficiency, calculated for a constant vapor pressure difference, increased with increases in vapor pressure difference indicating a possible adaptive mechanism for conditions of high evaporative demand. Day‐today increases in net photosynthesis, total leaf conductance to water vapor and mesophyll conductance were observed as plants were subjected to the same temperature and humidity treatments on progressive days. Growing plants under higher irradiances increased their photosynthetic rates and mesophyll conductance to CO2 but leaf conductance to water vapor was unaffected by irradiance pretreatment. Consequently, acclimation to radiation can only account for a small part of the day‐to‐day changes in gas exchange. Other possible explanations for these day‐to‐day changes were discussed. Significant differences were not observed among trees of ‘Campbell Valencia’ orange, ‘Parent Navel’ orange and ‘Frost Marsh’ grapefruit in responses of net photosynthesis and leaf conductance to temperature and humidity.
Comparative Studies of Net Photosynthesis and Transpiration of Some Citrus Species and Relatives
Authors: KHAIRI MOHAMED M. A. , HALL ANTHONY E. 
Published: April 2006

AbstractComparisqns were made between ‘Campbell Valencia’ orange (Citrus sinensis (L.) Osbeck), and ‘Gabon Cherry‐orange’ (Citropsis gabunensis (Engl.) Swing.), ‘Frost Lisbon’ lemon (Citrus limon (L.) Burm. f.) and ‘Eremolemon’ (Eremocitrus glauca (Lindl.) Swing. ×Citrus limon (L.) Burm. f.) and between diploid and autotetraploid ‘Lisbon’ lemons with respect to the influences of temperature and humidity on net photosynthesis and transpiration.Net photosynthesis, leaf conductance to water vapor and water‐use‐efficiency of Citropsis gabunensis were lower than with Citrus sinensis.‘Eremolemon’ had higher net photosynthesis and higher water‐use‐efficiency than ‘Lisbon’ lemon, but only small differences were observed between the two species in leaf conductance to water vapor. Small, nonsignificant, differences were observed between diploid and tetraploid ‘Lisbon’ lemons in responses of net photosynthesis and leaf conductance to temperature and humidity. Temperatures above 30°C and increases in vapor pressure difference caused declines in net photosynthesis and increases in vapor pressure difference resulted in decreases in leaf conductance to water vapor by all of the species used in these studies.
Adventitious Root Formation Induced by Gibberellic Acid and Regulated by the Irradiance to the Stock Plants
Authors: HANSEN JÜRGEN 
Published: April 2006

AbstractPea plants (Pisum sativum L. cv. Alaska) were grown from seeds for eleven days at different irradiances. Cuttings were then excised and rooted at 16 W × m−2. Gibberellic acid (GA3, 10−11 to 10−3M) was applied to the cuttings immediately after excision.Cuttings from stock plants grown at the highest level of irradiance (38 W × m−2) formed the lowest number of roots. An increasing number of roots per cutting was obtained by decreasing the irradiance to the stock plants. In cuttings from stock plants grown at low irradiances, low concentrations of GA3 (10−8 and 10−7M) promoted root formation further. No effect on rooting by these GA3 concentrations was observed when applied to cuttings originating from stock plants grown at the high irradiances. Root formation in all cuttings was inhibited by GA3 at concentrations higher than 10−6M. The degree of inhibition by GA3 was influenced by the irradiance pretreatment and was increased with an increase in the irradiance during the stock plant growth.Seeds from different years produced cuttings with different response patterns regarding the irradiance and GA3 effects on rooting.
The Effect of Various Alkaline Salts on the Glycolate Oxidase of Salicornia europaea and Pisum sativum in vitro
Authors: AUSTENFELD FRANZ‐ARNOLD 
Published: April 2006

AbstractThe response of glycolate oxidase from shoots of Salicornia europaea L. and from leaves of Pisum sativum L. to salt treatment during assay was studied by DCPIP reduction and O2 uptake. In Pisum there was found up to five times more glycolate oxidase activity per gram fresh weight than in Salicornia. However, the calculation of the specific activity pointed out that this result was caused only by the high level of enzyme protein in Pisum, and that specific activity from both species was of equal size.By the DCPIP method it was shown that in test media containing up to 1.0 M NaCl or KCl glycolate oxidase of Salicornia was of equal size compared with the control (medium without additional salts). With 2.0 M NaCl or KCl the activity decreased by about 80 and 30% respectively. Glycolate oxidase of Pisum was somewhat more salt sensitive. 1.0 M NaCl or KCl reduced the activity by about 35%. In the presence of 2.0 M NaCl or KCl the enzyme activity from Pisum was inhibited to about 80 and 60% respectively. By substituting sulfates for chlorides the activity of glycolate oxidase from both Salicornia and Pisum was stimulated strongly. 1.5 M Na2SO4 and 0.5 M K2SO4 (both are saturated solutions) caused an increase of glycolate activity from Salicornia of about 225 and 185% respectively, and from Pisum of about 50 and 30% respectively.Studying the response of glycolate oxidase to salt treatment by O2 uptake one must establish that with this method the degree of inhibition of enzyme activity at higher salt concentrations was always more severe than with dye reduction. Addition of 1.0 M NaCl or KCl to the assay medium caused an inhibition of glycolate oxidase activity from Salicornia of about 50% and from Pisum of about 60%. 2.0 M NaCl or KCl reduced the enzyme activity of both Salicornia and Pisum to nearly 10% of control activity. Furthermore, in contrast to DCPIP reduction no stimulating effect of sulfates on glycolate oxidase activity was detectable. Indeed, the inhibitory effect of sulfates was very slight. 1.0 M Na2SO4 caused a mean inhibition of glycolate oxidase activity of only 15% with both species, and in the presence of 1.5 M Na2SO4 50% of control activity was measured. At maximal K2SO4 concentrations (0.5 M) glycolate oxidase from both Salicornia and Pisum was also unaffected.It is supposed that the described salt tolerance of glycolate oxidase in vitro, possibly is due to an adaptation of the enzyme to high salt levels within peroxisomes in vivo.
The Intracellular Location of Abscisic Acid in Stressed and Non‐Stressed Leaf Tissue
Authors: LOVEYS B. R. 
Published: April 2006

AbstractThe intra‐cellular location of ABA was investigated in relation to its sites of synthesis. Chloroplasts were isolated from stressed and non‐stressed spinach leaves and their ABA content determined. Virtually all of the ABA from non‐stressed leaves was contained in the chloroplasts compared with only a small fraction of ABA isolated from stressed leaves. Chloroplasts prepared from turgid leaves and subsequently lysed in vitro retained most of their ABA and phaseic acid (PA) complement but this was removed with organic solvents.While the possibility of extra‐chloroplastic synthesis cannot be discounted the data indicate that stress‐induced ABA synthesis occurs in the chloroplast and that the ABA readily migrates from there to other parts of the plant.
Peroxidase and α‐Amylase Activities in Relation to Germination of Dormant and Nondormant Wheat
Authors: GASPAR THOMAS , WYNDAELE RITA , BOUCHET MIREILLE , CEULEMANS ETIENNE 
Published: April 2006

AbstractGermination capacity, and α‐amylase production in relation to the peroxidase and isoperoxidase activities in the grains of three varieties of wheat have been analysed and compared. A high percentage of germination and α‐amylase producation at 25°C are associated with low peroxidase activity of the isolated embryo. This correlation is lacking when the intact grain is considered. A 2‐day treatment at 4°C which further increases the percentage germination and enhances α‐amylase synthesis, lowers the activity of peroxidase in the embryos. A general decrease in activity of all the isoenzymes is observed.Based on the above data and on differences in the activity of the most cathodic isoperoxidasic bands, a hypothesis is put forward which suggests that a sufficiently low peroxidase activity and a minimum auxin level of the embryo are responsible for the onset of germination.
Isopropyl m‐Chlorocarbanilate and Its Hydroxylated Metabolites: Their Effects on Cell Suspensions and Cell Divison in Soybean and Carrot
Authors: DAVIS D. G. , HOERAUF R. A. , DUSBABEK K. E. , DOUGALL D. K. 
Published: April 2006

AbstractHydroxylated metabolites of isopropyl m‐chlorocarbanilate (chlorpropham) are found in intact soybean plants (Glycine max Merr.). The metabolites are isopropyl 2‐hydroxy‐5‐chloro‐carbanilate (2OH) and isopropyl 3‐chloro‐4‐hydroxycarbanilate (4OH). The phytotoxicity of these metabolites and chlorpropham was tested in cell suspensions and roots of intact soybean seedlings and cell cultures of carrot (Daucus carota L.). The growth of soybean cell suspensions was inhibited with 50 μM chlorpropham. Ten μM chlorpropham usually slowed initial growth of the cultures while 5 μM and 0.1 μM chlorpropham had no effect. The 2OH and 4OH metabolites had no significant effect on dry weight over the same concentration range. Some metabolism of chlorpropham, 2OH and 4OH occurred during 6 and 48 h of incubation with soybean cells. The results are interpreted to mean that all three analogs penetrated into the cells, were metabolized, and some of the metabolites excreted back into the medium. Mitotic index studies of intact 3‐day‐old soybean roots showed that 2OH inhibited mitosis to a greater extent than chlorpropham, whereas 4OH produced only a slight and insignificant reduction compared to controls. Chlorpropham, 2OH and 4OH (at 50 μM) all reduced the growth of wild carrot cultures grown in the presence or absence of 2,4‐D. Therefore, hydroxylation of chlorpropham at the 2′ or 4′ positions of the 5′ chlorinated benzene ring is not sufficient to render the compound nonphytotoxic in all plant systems.
Evidence for DNA Polymerase‐α and ‐β Activity in Sugar Beet
Authors: TYMONKO JOHN M. , DUNHAM VALGENE L. 
Published: April 2006

AbstractDNA polymerase preparations from incubated sugar beet (Beta vulgaris) root tissue exhibited multiple activities following DEAE‐cellulose chromatography and glycerol density gradient centrifugation (600‐fold purification). The two major polymerase activities eluted from DEAE‐cellulose differed in heat lability, pH and Mg2+ optima, and in response to ethanol, p‐hydroxymercuribenzoate, and N‐ethylmaleimide. Further purification by glycerol gradient centrifugation indicated the presence of a low molecular weight molecule (3.4 S), heterogeneous larger molecules (6.2, 6.8 S), and apparent aggregates (11–11.5 S). This investigation indicates similarities between sugar beet polymerases and the small (β) and large (α) molecular weight polymerases from mammalian systems.
Potassium and Rubidium Interaction in Their Absorption by Bean Leaf Slices
Authors: JACOBY BENJAMIN , NISSEN PER 
Published: April 2006

AbstractMesophyll cells of leaf slices of bean (Phaseolus vulgaris L.) absorb six to ten times more K+ than Rb+ from 0.1 mM single chlorides of these cations. Absorption of 42K+ from 0.1 mM42KCl is much more inhibited by low concentrations of Rb2SO4 than by K2SO4. The isotherm for K+ absorption is biphasic in the range 0.1–1.1 mM, and K+ is more effective than Rb+ in causing transition from phase 1 to phase 2.
Diurnal Fluctuations in Relative Water Content, Nitrate Reductase and Proline Content in Water‐stressed and Non‐stressed Wheat
Authors: RAJAGOPAL V. , BALASUBRAMANIAN V. , SINHA S. K. 
Published: April 2006

AbstractDiurnal variations in relative water content (RWC), nitrate reductase (NR) and proline content (PC) were studied at 3 h intervals during a 24 h cycle in the flag leaf of wheat (Triticum vulgare, v. Kalyansona) grown under stressed and non‐stressed conditions.RWC was lower in stressed plants than in non‐stressed ones throughout the 24 h period. Although it was lowest at 12 h, it recovered by 15 h. Non‐stressed plants maintained higher NR activity compared to those under stress. The enzyme activity during night was about the same as during day time in both types of plants. Compared to non‐stressed plants, stressed ones had lower NO3− content. Proline accumulation occurred under stress conditions and had a maximum at 12–15 h. Non‐stressed plants exhibited higher PC during night than day time.Changes in temperature and relative humidity were noted during the period and their influence on RWC, NR and proline was discussed.
Development of Asparagus plumosus Shoot Tips Grown in vitro
Authors: FONNESBECH MOGENS , FONNESBECH ANNE , BREDMOSE NIELS 
Published: April 2006

AbstractLateral shoot tips from young Asparagus setaceus (Kunth) Jessop (syn. A. plumosus Baker) shoots were grown on a modified Murashige and Skoog medium. Tips from 5 to 20 mm lateral shoots had significantly better growth and development than tips from lateral shoots (2 mm) still covered by leaf‐scale. The optimum temperature for growth and development of the explants was 17 to 24°C. The initial growth was fast at 24°C but stopped after about 4 weeks. At 17°C the growth was slow but in return the cultures continued to grow. Kinetin was necessary for growth. Without any kinetin all cultures died. Optimum growth was found with 2 mg/l kinetin. There was no growth at all with IAA alone. A low IAA concentration had no effect, but at high concentrations IAA inhibited the kinetin induced growth.
Devenir de la putrescine‐1,4‐14C chez Glycine max
Authors: LE RUDULIER DANIEL , GOAS GABRIELLE 
Published: April 2006

AbstractFate of Putrescine‐1,4‐14C in Glycine maxPutrescine‐1,4‐14C was supplied to young decotylized Glycine max (L.) Merr. cv. Chippewa plants growing under aseptic conditions on a liquid medium with nitrogen supplied either as ammonium chloride or nitrates. Whatever the source of nitrogen the diamine was quickly transformed to γ‐aminobutyric acid, succinic acid and malic acid; only a very minor part was utilized for the synthesis of polyamines. In the presence of ammonium chloride the putrescine catabolism may be slower than in the presence of nitrates. The results are explained by a weak isotopic dilution or by a diamine oxidase activity lower in “ammonium” plants than in “nitrate” plants; the two causes might co‐exist. The possibility of a diamine compartmentation has to be considered.
Influence of S‐ethyl Dipropylthiocarbamate (EPTC) on the Fatty Acid Composition of Wheat Leaf Galactolipids
Authors: KARUNEN P. , ERONEN L. 
Published: April 2006

AbstractWinter wheat (Triticum sativum L. cv. Nisu) was grown in sand which contained 0, 0.25, 0.5 and 1.0 mg S‐ethyl dipropylthiocarbamate (EPTC) per kg air dry sand. The galactolipids of leaves of 21‐day‐old seedlings were isolated by preparative thin layer chromatography. The fatty acids of the mono‐ and digalactosyl diglycerides were analysed by gas liquid capillary chromatography. The major fatty acids of the wheat leaf galactolipids were palmitic, palmitoleic, stearic, oleic, vaccenic, linoleic and linolenic acids (in the monogalactosyl diglyceride fraction of untreated plants 22.5, 2.4, 3.1, 5.2, 2.5, 51.1 and 1526.6 μg and in the digalactosyl diglyceride fraction 108.8, 2.3, 10.4, 9.9, 8.2, 42.3 and 1120.7 μg/g leaf fresh weight, respectively). Total fatty acid content of the mono‐ and digalactosyl diglyceride fractions was decreased by 85 and 87%, respectively, at 1 mg EPTC/kg sand, while decrease in the fresh weight of the leaves was 79%. The content of linoleic and linolenic acids/g fresh weight of the leaves was decreased in the monogalactosyl diglyceride fraction by 27 and 43%, respectively, while the content of all other fatty acids was increased. In the digalactosyl diglyceride fraction the content of both linoleic and linolenic acids/g leaf fresh weight was decreased by 55%. The content of palmitic and vaccenic acids was also decreased, whereas the content of other fatty acids remained at the level of the untreated samples. The general quality of the fatty acids in the mono‐ and digalactosyl diglyceride fractions was altered slightly by EPTC.
Regulation of Internodal Extension in Avena Shoots by the Inflorescence, Nodes, Leaves, and Intercalary Meristem
Authors: KONING ROSS , TKACZYK ANNE , KAUFMAN PETER B. , PHARIS RICHARD P. , MORF WILLIAM 
Published: April 2006

AbstractIt has been found in recent studies that the inflorescence and nodes (node‐pulvini) are the primary sources for native gibberellins in the Avena shoot, and that GA3 is the predominant gibberellin in the inflorescence. In the present work, linear growth of next‐to‐last internode is drastically reduced by removal of the inflorescence and last leaf. This growth is completely abolished when the nodes are also excised. It is restored fully by the addition of GA3 when the nodes are present, and restored only partially when the nodes are deleted. Internodal growth in Avena stem segments with basal node present is also restored by native GA3‐like substances extracted from Avena inflorescences and partially purified by silica gel partition column chromatography. Evidence from these studies, taken in toto, indicates that the inflorescence, nodes, and leaves supply gibberellins, leaves supply substrate, and nodes modulate the gibberellin growth response in next‐to‐last Avena internodes.