Biologia plantarum, 1975 (vol. 17), issue 6
Article
A kinetic study of phosphorus absorption by excised maize roots from flowing solutions with different phosphorus concentrations
Radmila Čížková-Macůrková, Z. Laštůvka
Biologia plantarum 17:385-391, 1975 | DOI: 10.1007/BF02921046
The effect of two different mechanisms of phosphorus ion transport from the nutrient solution volume to the surface areas of excised maize roots was studied under concentrations ranging from 0.01 mM to 50.0 mM KH2PO4. A modified technique of study of kinetic ion absorption was used. In the control series, the roots were placed in absorption solution without flow (the dominant mechanism of ion transport to the roots being diffusion), while in the experimental series the absorption solution was flowing round the roots at a rate of 0.162 cm s-1 (the dominant mechanism of ion transport to the roots being mass flow). The...
Development of water stress in kale leaves of different insertion levels
Jana Pospíšilová
Biologia plantarum 17:392-399, 1975 | DOI: 10.1007/BF02921048
The mutual relationship between the water potential (γ w ), its components, namely the osmotic potential (γ s ) and the pressure potential (γ p ), and the water saturation deficit (ΔW sat ) were determined in the leaves of different insertion levels. During the water stress development in kale plants induced by decreasing soil moisture theγ w decreased, parallely in all the leaves but the same decrease ofγ q was accompanied by the highest decrease of theγ...
Transpiration rate and intercellular diffusive resistance in the tobacco leaf
B. Slavík
Biologia plantarum 17:400-404, 1975 | DOI: 10.1007/BF02921050
The increase in the measured transpiration rate in tobacco leaves due to the experimentally decreased humidity of the bulk air was found to be significantly lower than the theoretical value calculated from the change of water vapour concentration gradients. Boundary layer and stomatal diffusive resistances remained unchanged under experimental conditions with no change of net photosynthetic CO2 uptake. This suggests an increase in intercellular diffusive resistance with an increase in water vapour concentration gradient which is the driving force of water vapour diffusive part of transpiration flux.
The increase can be ascribed to the...
A closed system for measurement of photosynthesis, photorespiration and transpiration rates
J. Čatský, Ingrid Tichá
Biologia plantarum 17:405-410, 1975 | DOI: 10.1007/BF02921051
An installation is described enabling measurements of photosynthesis, transpiration and dark respiration, and estimation of photorespiration rates at different carbon dioxide and oxygen concentrations, at different irradiances and leaf temperatures.
Comparison of the changes in net photosynthetic CO2 uptake and water vapour efflux during leaf ontogenesis with the differences between the leaves according to their descending insertion level
J. Václavík
Biologia plantarum 17:411-415, 1975 | DOI: 10.1007/BF02921052
The differences between leaves of different age according to their descending insertion level (starting from the youngest, 18th leaf) were compared with the changes occurring during the corresponding period of ontogenesis of the 18th unshaded leaf using the gas exchange [net photosynthetic CO2 uptake (P N ), water vapour efflux (E)] of the adaxial and abaxial surfaces of tobacco leaves as an example. Experimental elimination of the influence of shading during the involved period of ontogenesis of the 18th leaf manifested itself by a relatively slower decrease inP N and by fluctuation...
The effect of synchronizing dark period on populations ofScenedesmus quadricauda
V. Zachleder, J. Doucha, Eva Berková, I. Šetlík
Biologia plantarum 17:416-433, 1975 | DOI: 10.1007/BF02921054
Populations ofScenedesmus quadricauda grown in a continuous chemostatic regime and synchronized by light and dark intervals were exposed to continuous illumination. The effect of light on synthetic and reproduction processes during the time of the omitted dark period and in the subsequent cell cycle was studied. In general, the sequence of cellular processes and their mutual coupling remain the same as in the darkened population. Synthetic processes and photosynthetic activity are depressed during the period of protoplast fission also in the light. The synchronizing effect of the dark period in chlorococcal algae consists in reducing the developmental...
Transpiration in seven plant species colonizing a fishpond shore
J. Květ
Biologia plantarum 17:434-442, 1975 | DOI: 10.1007/BF02921056
In 7 species (Eleocharis palustrisR. Br.,Juncus bufonius L.,Gypsophila muralis L.,Trifolium repens L.,Agrostis stolonifera L.,Potentilla anserina L. andAchillea millefolium L.) growing in a gradient of habitats from aquatic to terrestrial, on a sandy fishpond shore in Southern Bohemia, Czechoslovakia, the daily course of transpiration rate and water content was assessed gravimetrically in their cut-off transpiring parts on two typical summer days. Transpiration rate was largely controlled by microclimate but depressions occurred inJuncus and in some species growing in the drier habitats. The highest...
Free nucleotides in the primary root of maize
Viera Finocchiaro, J. Kolek
Biologia plantarum 17:443-447, 1975 | DOI: 10.1007/BF02921057
Free nucleotides of the primary root of maize were extracted with 5% HClO4 and separated on a column of Dowex 1×8 ion exchanger in HCOO- cycle. A two-step elution gradient (HCOOH, HCOOHNH4) was used for the elution of the nucleotides. The incorporation of32P into the nucleotides was followed at different time intervals and also in young and more mature root tissues. The nucleotides AMP, GMP, ADP, GDP, and ATP were identified. Labelled phosphorus was found in ATP after 30 s, in ADP after 3 min, and in AMP after 5 min incubation of the roots. More mature roots (18 days) contained higher amounts of AMP than...
Glucose-6-phosphate dehydrogenase in tobacco callus strains differing in their growth and their requirement for auxin and cytokinin
Věra Hadačová, M. Kamínek, J. Luštinec
Biologia plantarum 17:448-451, 1975 | DOI: 10.1007/BF02921058
The cytokinin-autonomous strain (As) of tobacco callus differs from the original cytokinin-dependent strain (D) and from the cytokinin- and auxin-autonomous strain (A4) by a significantly lower activity of glucose-6-phosphate dehydrogenase (G-6-PDH). Changes in the total G-6-PDH activity were associated with differences in the number of G-6-PDH isozymes. The As strain contained only one isozyme, four isozymes were found in D and A4 strains.
Brown rot of wood as a model for studies of lignocellulose humification
V. Rypáček, Marie Rypáčková
Biologia plantarum 17:452-457, 1975 | DOI: 10.1007/BF02921059
Humus substances synthesis was investigated in the course of birch wood decomposition by a brown-rot fungusPiptoporus betulinus. With progressing decomposition of wood by brown rot the proportion of high molecular weight humic acids is gradually increased at the expense of fulvic acids, the amount of which is proportionally lowered. The high molecular weight humus constituents are not accumulated in wood decomposed by a laccase producing white-rot fungi despite the availability of suitable phenolic substrates; the low molecular weight fraction of fulvic acids is permanently higher than the fraction of humic acids. The function of laccase in...
Chemotropic effect of metal cations onSinapis alba L. roots as affected by some factors
Z. Konarzewski, S. Gumiński
Biologia plantarum 17:458-467, 1975 | DOI: 10.1007/BF02921061
Chemotropic effects exerted by metal cations have been investigated simultaneously with their influence on the increments ofSinapis alba roots cultivated in dark and light. The effects of Na-EDTA and Na-humate and its fractions, as well as the interaction of these substances with cations have also been studied. Chemotropics have been administered in agar-agar to the ends of roots growing on glass plates. Chemotropic and growth effects were exerted by Cu2+, Fe2+, Fe3+ and Ca2+ cations. The light strongly changed the effects of all but Cu2+ cations. Both Na-EDTA and humante appeared to be...
The influence of humic acids on phytase activity isolated from wheat seeds
F. Pospíšil, Marie Hrubcová
Biologia plantarum 17:468-474, 1975 | DOI: 10.1007/BF02921062
Humic acids can inhibit the activity of wheat phytase in model experiments, because they are able to form complexes with hexainositol phosphates and have considerable adsorption properties. Decarboxylated humic acids do not show any inhibitory effects.
The effect of simultaneous short term action of streptomycin and humate on plants
S. Lhotský
Biologia plantarum 17:475-480, 1975 | DOI: 10.1007/BF02921063
Humate (10 mg l-1) supplemented to streptomycin solutions (0.1 and 1 mM) stimulates growth of germinating wheat and barley grains and of apical cuttings ofCrassula portulacea after 24 h treatment. It does not, however, prevent formation of albinic leaves. Albinism induced by the streptomycin alone and by streptomycin in presence of humate is irreversible and can be removed neither by an iron salt nor by a chelate added to the nutrition solution or applied on the leaves. Cells of plants treated with streptomycin and humate are larger than those of plants treated with the streptomycin alone. The same is true for plastids which in both...
Book Review
Cushing, D. H.: The productivity of the sea
P. Javornický
Biologia plantarum 17:391, 1975 | DOI: 10.1007/BF02921047
Kessel, R. G., Shih, C. Y.: Scanning electron microscopy in biology. A students' atlas on biological organization
Ingrid Tichá
Biologia plantarum 17:399, 1975 | DOI: 10.1007/BF02921049
Etherington, J. R.: Environment and plant ecology
J. Čatský
Biologia plantarum 17:415, 1975 | DOI: 10.1007/BF02921053
O'Connor, M., Woodford, F. P.: Writing scientific papers in English
J. Čatský
Biologia plantarum 17:433, 1975 | DOI: 10.1007/BF02921055
Street, H. E. (ed.): Tissue culture and plant science 1974
J. Tupý
Biologia plantarum 17:457, 1975 | DOI: 10.1007/BF02921060