The incorporation of uridine-³H into the shoot apices of photoperiodically induced and non-induced plants of Chenopodium rubrum L.

Feideta Seidlová

Biologia plantarum 14:241-248, 1972 | DOI: 10.1007/BF02935847

The influence of photoperiodic induction on the incorporation of uridine-³H into the shoot apices ofChenopodium rubrum was studied using the technique of autoradiography. No increase in uridine incorporation was detected either during induction lasting three days or immediately after its termination. Pyroninophylia likewise did not rise. However, changes in uridine incorporation related to morphogenetic activity during leaf formation and later during differentiation of inflorescences were well marked. The distribution of label in the nucleus immediately after three inductive cycles shows the ratio of extranucleolar to nucleolar incorporation...

Time dynamics of primary root branching inPisum sativum L.

Albína Klasová, J. Kolek, J. Klas

Biologia plantarum 14:249-253, 1972 | DOI: 10.1007/BF02935848

Time-intervals in which the branching of primary roots occurs (the formation of lateral root primordia and the appearance of laterals on the surface of primary roots) were determined by a statistical method in several cultivars of pea. The same time-determination of the branching of the primary root in all studied cultivars was found indicating a genetic regulation of this process.

The response of short day plantChenopodium rubrum L. to abscisic acid and gibberellic acid treatment applied at two levels of photoperiodic induction

J. Krekule, B. Hořavka

Biologia plantarum 14:254-259, 1972 | DOI: 10.1007/BF02935849

Abscisic acid (ABA) (5 x 10^-4M and 5 x 10^-5M) and gibberellic acid (1 x 10^-4M) was applied to the plumula ofChenopodium plants with partly (one dark period) or completely (three dark periods) fulfilled photoperiodic requirements for flowering. Morphological and cytoogical criteria were used to investigate the time-course of the differentiation of the treated shoot apices. Both substances were ineffective in increasing the mitotic activity of the shoot apex at the suboptimal level of induction. The degree of branching was temporarily stimulated by ABA and GA treatment under these conditions. Moreover, GA caused...

Photosensibility of pinus banksiana LAMB. Seeds

Monique Orlandini, Camille Bulard

Biologia plantarum 14:260-268, 1972 | DOI: 10.1007/BF02935850

Germination ofPinus banksiana seeds is controlled by the photoreversible phytochrome reaction. The seeds, even unimbibed, are sensitive to red light. At 660 nm, the energy required to promote germination to the same order of magnitude is much higher for unimbibed seeds than for the imbibed ones. In both cases it is possible to reverse the effect of a single red light irradiation by applying far red light (730 nm).

Histochemical studies on the distribution of 5-nucleotidase in the germinating pollen grains ofEschscholtzia californica cham.

H. B. Tewari, C. P. Malik, P. P. Sood

Biologia plantarum 14:269-272, 1972 | DOI: 10.1007/BF02935851

The present paper incorporates a detailed study on the distribution of 5-nucleotidase in the germinating pollen grains ofEschscholtzia califomica. The intense activity of this enzyme has been found in the wall of pollen grains and pollen tubes and small positive granules in the lumen of both in the pollen grains and pollen tubes. The presence of this enzyme in the wall is presumably connected with the permeability and transport process and growth regulation of the pollen tubes.

The role of endogenous growth regulators in the differentiation processes of walnut (Juglans regia L.)

Z. Sladký

Biologia plantarum 14:273-278, 1972 | DOI: 10.1007/BF02935852

The character of endogenous growth substances was investigated in developing buds, young fruits and mature walnut leaves. The relatively high content of auxins and gibberellin-like substances was found by means of bioassays in the youngest primordia of vegetative buds. The level of auxins drops in the further course of primordia transformation into the staminate catkins. The development of leaf-buds is characterized by the accumulation of inhibitory activity as revealed by theAvena bioassay, whereas the data obtained from the lettuce bioassay indicate a pronounced stimulation. The onset of terminal bud development is also accompanied by inhibitions...

Biosynthesis of the glucobrassicin aglycone from¹⁴C and¹⁵N labelled L-tryptophan precursors

M. Kutáček, Marie Králová

Biologia plantarum 14:279-285, 1972 | DOI: 10.1007/BF02935853

The formation of the isothiocyanate group of the aglycone of glucobrassicin (Glubr) an indole glucosinolate present in relatively large quantities in plants of the familyBrassicaceae, was studied. Labelled Glubr was synthesized from L-tryptophan-3-¹⁴C-amino¹⁵N in winter rape hypocotyl segments. After extraction it was finally isolated in a crystalline state by mixed crystallization with added inactive Glubr tetramethylammonium salt. The specific activity of¹⁴C and the atoms % excess¹⁵N were determined in both the precursor and the product. The ratio¹⁴C/¹⁵N as well as the values...

Senescence and IAA Induced Elongation of Oat Coleoptile Sections

Monique Fantinet

Biologia plantarum 14:286-292, 1972 | DOI: 10.1007/BF02935854

Five mm sections excised from 20, 30 and 40 mm long coleoptiles were transferred into a indole-3-acetic acid (IAA) solution after an incubation in a medium containing buffer and sucrose without IAA. The ability of sections to elongate in dependence on IAA treatment was rapidly decreased at a temperature of 23 °C within a period of time depending both on the duration of incubation and on the age of coleoptiles from which sections were obtained. Under the same conditions of incubation and age the same decrease of the ability of sections to elongate at 4 °C was, however, observed only after a period fourfold longer than at 23 °C. Incubation of sections...

Book Reviews

Ingrid Tichá, M. Kamínek, Jana PospíŠilová, J. Čatský

Biologia plantarum 14:318-319, 1972 | DOI: 10.1007/BF02935861

Variable resistance to water transport in leaf tissue of kale

Jana Pospíšilová

Biologia plantarum 14:293-296, 1972 | DOI: 10.1007/BF02935855

The constant values of water potential gradient accompanying various levels of water flow rate were found in kale leaf tissue segments. This constancy might indicate the decrease of resistance to water flow as flow rate increased and this decrease of resistance was confirmed.

Structural and Soluble Proteins of Two Lethal Chlorophyll Mutants ofArabidopsis thaliana Cultivated on a Sucrose Medium

JiŘina Švachulová, VĚra HadaČová

Biologia plantarum 14:297-301, 1972 | DOI: 10.1007/BF02935856

Structural proteins of both chlorophyll - deficient mutants, extracted with a phosphate buffer solution pH 8,3, using Triton X-100 as detergent, exhibit, in comparison with normal plants, a faint cathodic fraction giving positive staining for lipoproteins and containing chlorophyll. No differences in soluble proteins were found between the mutants and control plants. The pattern of the individual protein fractions differs according to the method employed.

Virus origin of the oat sterile dwarf disease

J. Brčák, O. Králík, J. Vacke

Biologia plantarum 14:302-304, 1972 | DOI: 10.1007/BF02935857

Virus particles (approximately 73 nm in diam.) usually showing an inner capside (45 nm in diam.) and similar to diplornaviruses, esp. reoviruses, were found in some cells of enations inAvena sativa andArrhenatherum elatius leaves infected with the oat sterile dwarf disease (OSDD). (The same virus particles were described by the authors in 1966 in the leafhopper vector.)Mycoplasma-like microorganisms found in1969 in the OSDD leafhopper vector were absent in OSDD infected plants. Tetracycline did not affect symptom development in plants and did not alter the infectivity of the vector.Therefore, OSDD is apparently of...

Problems of the Morphogenesis of a thallus Achlya ambisexualis ♀ J. K. RAPER

J. P. Beet

Biologia plantarum 14:305-307, 1972 | DOI: 10.1007/BF02935858

The author compares the activity of ¶-fluorophenylalanine and the effect of a medium without nitrogen on the morphogenesis of hyphae of Achlya ambisexualis ♀. A hyperramification often corresponds to a mode of prelethal development and is observed in the same conditions as an asexual multiplication.

The Regulation of Nitrate Reductase, Nitrite Reductase, and Glutamate Dehydrogenase in Excised Pea Roots by Some Exogenous Amino Acids

J. Sahulka

Biologia plantarum 14:308-311, 1972 | DOI: 10.1007/BF02935859

The effect of growth retarding amino acids (L-aspartic acid,L-leucine,L-methionine, andL-threonine) on nitrate reductase (NO₃R), nitrite reductase (NO₂R), and NADH₂ dependent glutamate dehydrogenase (GDH) in excised pea roots was followed,L-methionine andL-threonine slightly depressed NO₃R activity,L-aspartic acid enhanced NO₂R and GDH activities.L-methionine andL-threonine also slightly decreased nitrate uptake. The results obtained are discussed in connection with the growth effects of the amino acids investigated.

Notice to Biologia Plantarum Contributors

Biologia plantarum 14:312-317, 1972 | DOI: 10.1007/BF02935860

Erratum to: A Nicotinamide Adenine Dinucleotide Phosphate Phosphatase from Chlorella

R. Chopowick, G. F. Israelstam

Biologia plantarum 14:320, 1972 | DOI: 10.1007/BF02935862