Prof. Jaroslav Smolak - deceased

J. Brčák

Biologia plantarum 14:N1, 1972 | DOI: 10.1007/BF02920908

The effect of the transmission of the beet mosaic virus on the variability of its incubation period

J. Smrž

Biologia plantarum 14:1-10, 1972 | DOI: 10.1007/BF02920896

The variability of the incubation period of the beet mosaic virus [Beta virus 2(Lind) Smith] was investigated in a three year experiment. The virus was transmitted by the black bean aphid (Aphis fabaeScop.) or by a mechanical inoculation onAmaranthus caudatus L. Variability characterized by the standard deviation indicates a closer distribution of measurements when the virus was transmitted by mechanical inoculation. The differences in variability of the incubation period between the two methods of virus tramission are statistically significant; dispersion and standard deviation are lower after mechanical inoculation. The average length...

Direct proof of phosphorus oxytriamide in exudates of decapitatedPhaseolus vulgaris plants

L. Ondráček, J. Novák

Biologia plantarum 14:11-13, 1972 | DOI: 10.1007/BF02920897

Phosphorus oxytriamide PO(NH₂)₃ was proved chromatographically in the exudate of decapitatedPhaseolus vulgaris plants. This fact verified the presumption that covalent compounds of phosphorus and nitrogen enter roots without previous hydrolysis.

Diurnal oscillatory movements of growing leaves of tobacco

M. Spurný

Biologia plantarum 14:14-27, 1972 | DOI: 10.1007/BF02920898

The analysis of diurnal oscillatory movements of tobacco leaves was used in the diagnosis of viral infection of plants. The oscillatory helices circumscribed by a growing leaf of a healthy plant were regular, but some deviations, particularly in the transition points, were recorded.In order to make clear the cause of these irregularities of trajectory, the course of elongation of leaf petiole and blade in relation to localization and shift of zones of elongation during ontogenesis was analysed. The present analysis is similar to that described by the author's earlier experiments with pea roots. Oscillatory curves circumscribed by petiole, projected...

Comparison of effects of calcium deficiency and IAA on the pumpkin plant (Cucurbita pepo L.)

M. Dvořák, Jana Černohorská

Biologia plantarum 14:28-38, 1972 | DOI: 10.1007/BF02920899

In pumpkin plants suffering from calcium deficiency growth of the root system is characteristically suppressed. A biochemical symptom of calcium deficiency is a decrease or even complete disappearance of activity of one of the isoperoxidases (isoperoxidaseD). In the present study the two characteristics were used to compare the effects of calcium deficiency and of IAA in the supraoptimal concentration of 10^-5 M. Peroxidases were separated by centrifugal fractionation: peroxidasesA andB were found in the sediment corresponding to the mitochondrial fraction, peroxidaseD in the supernatant. It was not possible, however,...

The effect of CCC on the nitrogen compounds content in rape plants and their frost hardiness. Relation to the conditions of day-length and temperature

Alina Kacperska-Palacz, Barbara Wciślińska

Biologia plantarum 14:39-47, 1972 | DOI: 10.1007/BF02920900

Both CCC and cold (5°C) treatment gave rise to an increased content of the water-soluble proteins in leaf tissue of the winter rape, irrespective of the day length. This effect was accompanied by a decrease of the insoluble nitrogen compounds content, mainly under theLD (the 16 hour day). The applied retardant also stimulated the consumption of the structural compounds induced by low temperature.Low temperature treatment hardened plants more distinctly than the CCC application. The frost hardening effect of CCC andSD (the 8 hour day) was manifested only at 20°C and it disappeared at 5°C.Changes in frost hardiness were not correlated...

The effect of (2-chloroethyl)trimethylammonium chloride (CCC) and gibberellic acid on the growth and development of wheat cultivated under red or blue light

J. Petr

Biologia plantarum 14:48-51, 1972 | DOI: 10.1007/BF02920901

The effect of CCC and GA₃ on the growth and development of spring wheat (Triticum aestivum L.) cultivated under predominantly red (500-700 nm) or blue (400-500 nm) light was investigated. Red light enhanced the development of wheat during the exponential phase of growth. This effect presumably implicated the promotion of gibberellin synthesis under red light. The strong inhibitory action of CCC under red light (the inhibition was lower under blue light) might be interpreted in a similar way. The growth became more intensive under blue light after caring and was accompanied by increased susceptibility to giberellic acid treatment.

A cybernetic model of growth correlation in young apple trees

L. S. Jankiewicz

Biologia plantarum 14:52-61, 1972 | DOI: 10.1007/BF02920902

Growth correlations among lateral shoots of one-year-old apple treesMalusMill., were described. The existence of a mechanism was postulated through which small original differences between buds or young shoots are quickly augmented, thus leading to differentiation of long shoots and short shoots. Existing hypotheses do not seem sufficient for explaining correlative phenomena of this type; a cybernetic approach was therefore applied. Studying growth correlations in terms of cybernetic revealed that previous hypotheses concerning correlations do not contradict each other as often thought, but depict different links in a more general chain of events....

Cytotaxonomical studies of four sterile species of the genusAllium

O. Konvička

Biologia plantarum 14:62-70, 1972 | DOI: 10.1007/BF02920903

The meioses of four sterile species in the genusAllium which develop bulblets in the inflorescences instead of seeds were compared, namelyAllium sativum, A. cepa var.viviparum, A. carinatum, andA. oleraceum. The most important of them,A. sativum, is an ancient cultivated plant and its vegetative reproduction prevents it from more rapid evolution such as is known in generatively propagated cultivated plants.A. sativum shows fully normal meiosis. After the disintegration of the tetrads, however, the blockade of 1. pm takes place. The cause of the blockade has not yet been cleared up. Removing of bulblets appeared...

Function of phenolic substances in the degradation system of indole-3-acetic acid in strawberries

Liya V. Runkova, Elwira K. Lis, M. Tomaszewski, R. Antoszewski

Biologia plantarum 14:71-81, 1972 | DOI: 10.1007/BF02920904

The homogenate of different strawberry organs inhibits the degradation of IAA in the presence of horse radish peroxidase, while intact strawberry tissues are able to degrade IAA. The chemical nature of peroxidase inhibitors present, in strawberry tissues was in vestigated. Using paper chromatography the following polyphenolic substances inhibiting peroxidase activity were identified: chlorogenic, caffeic, ellagic, gentisic, gallic, and vanillic acids, quercetin and pelarginidin. Monophenolic compounds, also present in strawberry, such as p-hydroxy-phenyloacetic acid and p-hydroxybenzoic acid, are strong stimulators of IAA oxidase. Abscisic acid in...

Some factors affecting the seed set afterin vitro pollination of excised placentae ofNicotiana tabacum L.

Věra Balatková, J. Tupý

Biologia plantarum 14:82-88, 1972 | DOI: 10.1007/BF02920905

The paper deals with the effect of some factors on the set of mature seeds in artificially pollinated excised placentae cultivatedin vitro.It was revealed that both the degree and the variability of the seed set depend on the age of the experimental flowers. The best results were achieved using placentae excised from the flowers collected 1 to 3 days after anthesis.The technique of pollination which consists in applying pollen onto a certain site of the placenta was substantially more successful than dusting pollen over the entire placenta surface or sowing pollen on the nutrient medium in close proximity to placentae.It was confirmed...

Water loss from leaves as affected by previous exposure in au atmosphere saturated with water vapour

J. Pazourek

Biologia plantarum 14:89-91, 1972 | DOI: 10.1007/BF02920906

The transpiration rate of detached leaves exposed in the atmosphere saturated with water vapour increased after a certain time. This time as well as the shape of the transpiration curves varied according to the duration of the exposure of the leaves in the humid atmosphere.

Ethylene production in the leaves of basket willow (Salix viminalis L.) during the growing season

F. Plhák

Biologia plantarum 14:92-95, 1972 | DOI: 10.1007/BF02920907

The production of ethylene in the leaves ofSalix viminalis L. increased gradually from May till October. The emanation from the leaves, the main constituent of which was ethylene, inhibited the extension growth and the formation of the dry matter of rye seedlings more or less equally during the whole growing season. This indicates that the effect of ethylene on the growth is not, to any great extent, dependent on its concentration.