Electrophoretic investigation of phenol oxidases in stratified apple seeds

A. Podstolski, Barbara Gajewska, St. Lewak

Biologia plantarum 16:163-166, 1974 | DOI: 10.1007/BF02920909

The substrate specificity of apple seeds phenol oxidases was investigated in polyacrylamide gel electropherograms. The nonspecifico-diphenol oxidases were distinguished as well as fractions showing the specificity for some structural elements of substrate molecule. The role of particular oxidases in phloridzin transformations in apple seed was discussed.

Book reviews

Z. Šesták, Ingrid Tichá

Biologia plantarum 16:167, 1974 | DOI: 10.1007/BF02920910

DNA synthesis during the early stage of germination in the barley embryo meristems and its inhibition by N-methyl-N-nitrosourea

Stanislava Fousová, J. Velemínský, T. Gichner, V. Pokorný

Biologia plantarum 16:168-173, 1974 | DOI: 10.1007/BF02920911

3 peaks of DNA synthesis were observed in the barley embryo of seeds, germinating for 49 h in running tap water at 25°C. The first peak, found after 22h, was formed by S-cells in the roots and in the 1st leaf meristem. The second peak (after 34-37h) and third peak (after 46-49 h) represents the S-cells in the roots, apex and 1st, 2nd and 3rd leaf meristems. Application of N-methyl-N-nitrosourea for 3 h at the onset of germination inhibited the rate of DNA synthesis and postponed the peaks of DNA synthesis in individual meristems of the embryo.

Effect of the change of leaf angle arrangement on productivity of maize (Zea mays L.) stands

J. Vidovič

Biologia plantarum 16:174-183, 1974 | DOI: 10.1007/BF02920912

Leaf angles, frequency distribution of leaf area inclinations, leaf area index, amount of intercepted radiation, biological, vegetative and grain yields and grain yield proportion of biological yield were determined in maize stands of two population densities, 55 555 plants ha^-1 (S₁), and 80 000 plants ha^-1 (S₂). Also the effect of the artificial change of leaf angle upon these indices was studied. We classified normal maize stand (N) as the interstage between a planophile and a plagiophile type of canopy, that with artificially changed leaf angle (V) as an erectophile type of...

Effect of temperature on the division of isolated cells from leaves ofCalystegia sepium (L.) R. Br.

M. Sandmeier

Biologia plantarum 16:184-193, 1974 | DOI: 10.1007/BF02920913

Cells mechanically isolated from homogenized leaves ofC. sepium dividein vitro. The rate of cell division is strongly influenced by temperature with the optimum between 31 and 34 °C. The rate of cell division increases proportionally with a rise in temperature up to 31 °C and is accompanied by a reduction in the length of the preparatory phase of the division. A supraoptimal temperature (40 °C) inhibits or stops the cell division which can be restored provided that the cells are transferred to 31 °C. If the preparatory phase to the commencement of cell division is accomplished at 17 °C the cells then exposed to 31 °C divide more rapidly...

The free movement of¹⁴C-labelled organic compounds from intact apple seeds to growing fruitlets and shoots

Maria J. Grochowska

Biologia plantarum 16:194-198, 1974 | DOI: 10.1007/BF02920914

Indole-3-acetic acid (IAA-1¹⁴C, IAA-2¹⁴C) and gamma-aminobutyric acid labelled with¹⁴C were applied in lanoline to the surface of intact seeds or inserted into seeds of growing apple fruitlets or to the cut surface of the pericarp. Their translocation in trees was checked by means of autoradiography or by a low background Geiger-Müller counter. Auxin applied to the top of intact seeds, or inserted into the seeds was translocated and distributed within the pericarp, spur tissues and shoots below. The translocation of gamma-aminobutyric acid from seeds suggests that the capacity of apple seeds for extensive interchange...

Glucose-6-phosphate dehydrogenase isoenzymes in root growth zones ofVicia faba

Věra Hadačová

Biologia plantarum 16:199-203, 1974 | DOI: 10.1007/BF02920915

The specific activity of glucose-6-phosphate dehydrogenase (G-6-PD) in growth zones ofVicia faba roots is increasing with cell maturation and differentiation. Changes in the total activity of G-6-PD are not associated with a change in the number of G-6-PD isoenzymes. Five G-6-PD isoenzymes were found in all root growth zones. Some differences were found in the activity of individual isoenzymes.

The oxidation of indole-3-acetic acid by supernatants of homogenates of barley leaves infected with powdery mildew (Erysiphe graminis DC.) and by extracts from the surface of barley roots

J. Benada, H. Klusák

Biologia plantarum 16:204-209, 1974 | DOI: 10.1007/BF02920916

The supernatants obtained after the centrifugation of the homogenates of healthy barley leaves and the extracts from the surface of barley roots can enzymatically oxidize exogenously supplied IAA in the presence of Mn²⁺ ions and 2,4-dichlorophenol. On the contrary, IAA oxidation is strongly inhibited or does not occur at all in the supernatants from the leaves infected with powdery mildew (Erysiphe graminis DC.) and in the extracts from the surface of both healthy and diseased leaves. The supernatants from diseased leaves inhibit IAA oxidation proportionally to the amount of the added supernatant. That indicates that natural inhibitors...

Uptake of potassium and its influence on growth and magnesium uptake by groundnut (Arachis hypogaea L.) plants

N. K. Fageria

Biologia plantarum 16:210-214, 1974 | DOI: 10.1007/BF02920917

Groundnut (Arachis hypogaea L.) plants were grown for 55 days in dilute nutrient solution at varying concentration of potassium. Data are recorded for the rate of uptake of potassium, magnesium and growth response. Over the concentration range studied, the rate of absorption of potassium followed Michaelis-Menten kinetics with a Michaelis constant (K_m) of 0.06×10^-3M. Identical response curves were observed for either total growth or total uptake. Maximum yield was obtained at a concentration of about 200 μM potassium. Increasing concentrations of potassium depressed the uptake of magnesium.

The significance of the cotyledons for the formation of diamine oxidase in pea plants

V. Růžička, J. Minář

Biologia plantarum 16:215-223, 1974 | DOI: 10.1007/BF02920918

The effect of the removal of cotyledons on the growth of etiolated pea plants and on the changes in diamine oxidase activity were followed. Plants with removed cotyledons showed higher diamine oxidase activity both in the shoots and in the roots when expressed per fresh weight unit. Higher diamine oxidase activity can be found also in the remaining cotyledon when one of the two cotyledons is removed (when expressed per fresh weight unit and per cotyledon).The plants belonging to those experimental variants in which a higher diamine oxidase activity was established (plants without cotyledons) had simultaneously a high content of its substrates....

The inhibition of TMV reproduction in tomato leaves inducedCladosporium fulvumCooke

Miloslava Hanušová

Biologia plantarum 16:224-226, 1974 | DOI: 10.1007/BF02920919

Taking into consideration simultaneous infection of tomato leaves withCladosporium fulvumCooke and TMV, the fungus infection inhibits the TMV reproduction. This inhibition occurs in the plant irrespective of the sequence of pathogen inoculation and reaches even 70 per cent. The fungus spores applied to the TMV purificate inhibit the TMV infection, as well.

Morphological and anatomical changes in the roots of apple seedlings treated with morphactin IT 3456 and α-naphthalene acetic acid (NAA)

M. Smoliński, M. Saniewski, Janina Pieniążek

Biologia plantarum 16:227-229, 1974 | DOI: 10.1007/BF02920920

On the roots of the unchilled apple seedlings treated with morphactin many deformed adventitious shoots were formed, whereas when the roots were dipped in the mixture of morphactin and NAA more adventitious roots were produced than when only NAA was used. The growth of these lateral roots was greatly inhibited. Similar interaction of NAA with morphactin in the development of roots was obtained when the chilled seedlings were treated with these growth regulators before the buds developed. The sections of the roots from all the treatments were made and the anatomy studied.

The effect of exogenously supplied hydroxylamine on glutamate dehydrogenase, nitrate reductase, and nitrite reductase in isolated pea roots

J. Sahulka

Biologia plantarum 16:230-233, 1974 | DOI: 10.1007/BF02920921

Hydroxylamine added to the nutrient medium in sublethal concentrations (0.2 to 1.0 mN) enhanced NADH₂ dependent glutamate dehydrogenase activity in isolated pea roots. The increase in activity depended on proteosynthesis and was lower in the presence of NO₃^- and NH₄⁺ ions. The induction of nitrate reductase and of nitrite reductase was partly inhibited by sublethal hydroxylamine concentrations.

Water stress development in kale leavesin situ and in water supplied cut leaves

Jana Pospíšilová, Jarmila Solárová

Biologia plantarum 16:234-236, 1974 | DOI: 10.1007/BF02920922

The development of temporary water stress during the day-light hours, characterized by a decrease of the values of the water potential (ϕ_w) and increase of the values of water saturation deficit (ΔW_sat) was found not only in the leaves of intact kale plants but also in cut leaves with their petioles immersed in water. These results indicate that the leaf resistance to water transport could not be supposed as negligible. The same decrease of ϕ _w was accompanied with the higher increase of ΔW_sat in cut leaves than in leavesin situ.

Speeifle isoperoxidases in roots

Th. Gaspar, M. Dubucq, P. Van Hoof

Biologia plantarum 16:237-240, 1974 | DOI: 10.1007/BF02920923

Using starch gel electrophoresis, a group of anodic isoperoxidases which is revealed byo-dianisidine (not by guaïcol) in the soluble fraction of roots proteins from lentil, pea, sugarbeet and maize is never found in corresponding extracts from stems. These root specific peroxidases do not show IAA-oxidase activity as revealed byp-dimethylaminocinnamaldehyde on the gels. They could not serve as a rhizogenesis index since they do not appear from the early beginning of root growth.

Stewart, P. R., Letham, D. S. (ed.): The ribonucleic acids

M. Kamínek

Biologia plantarum 16:240, 1974 | DOI: 10.1007/BF02920924