Synchronization of the cultures of Scenedesmus quadricauda (Turp.) Bréb

J. Komarek, J. Simmer

Biologia plantarum 7:409, 1965 | DOI: 10.1007/BF02920686

Cultures of the coenobial four-celled chlorococcal algaScenedesmus quadricauda were synchronized. Ontogeny of the species, proceeding analogously to that of the unicellular forms, was studied; however, the cells in the coenobium ripen successively. The paramoters of the synchronized cultures were followed and according to the obtained results an objective method of evaluation of the synchronization-degree of the algal cultures, on the basis of information theory, was suggested.

Nutritional effects on the hop curl disease and comparison of the chemical composition of diseased and healthy hop plants

V. Průša, J. Pirkl, J. Böhmová

Biologia plantarum 7:425-436, 1965 | DOI: 10.1007/BF02920687

Whereas experiments directed towards proving the infectious character of the hop curl disease did not give reliable proof of its virus character (we have not been able to transfer it neither by cuttings nor by graft), but made possible its differentiation from the English nettlehead hop virus disease, the practical experiences and results presented in this paper show that nutritional conditions essentially affect the known variability of the external manifestations of the hop curl disease. Especially such nutrients play a role which with the normal fertilising techniques are not returned to the soil in sufficient quantity. Since the hop curl disease...

Morphology and function of the Golgi apparatus

Ivan Hršel

Biologia plantarum 7:437-448, 1965 | DOI: 10.1007/BF02920688

The polymorphism of the dictyosomes in the root meristeme ofFagopyrum is connected with their various functions in secretory processes and cell differentiation. The dictyosomes containing vesicular dilatations of the cisternae, which in this object occur more frequently than in others, probably participate in a similar way as the Golgi apparatus of the animal cell in the formation of lysozomes, in the formation of elements belonging to the group of dense bodies analogical lysozomes. These bodies are present in large numbers in the cytoplasm of cells, containing dictyosomes with vesicular dilatations. The other forms of the dictyosomes reveal...

Influence of soil heterogeneity on water regime and yields of lucerne, sugar beet and wheat

Jiří Úlehla, Ludmila Zichová, Zdeněk Baňoch

Biologia plantarum 7:449, 1965 | DOI: 10.1007/BF02920689

Lucerne plants in the first crop year as well as plants of spring wheat from different sites of the respective experimental plots showed differences in sap exudation from detopped roots or from stumps of the main shoots, reflecting differences in properties of the soil profile. The differences in sap exudation were observed at a time when the plants did not show any visible differences in water availability.Differences in the water potential deficit of the leaf blades of lucerne plants in the second crop year and of sugar beet plants, related to differences in soil profile properties, were observed in another series of experiments. Sugar beet plants...

Studies of some ways in which carrot mosaic virus can be transmitted

J. Chod

Biologia plantarum 7:463-468, 1965 | DOI: 10.1007/BF02920690

The transmission of carrot mosaic virus (CMV) by the crude sap to 11 varieties of plants from 4 families was demonstrated. From these plants the virus could be transferred back to a healthy carrot cultivated from the seed in isolation. The incubation time required for the appearance of the symptoms of CMV was 7-20 days. The plants on which mosaic or spot symptoms appeared on the leaves after transfer by the sap at temperatures below 15°C remains habitually healthy after the transfer of virus at higher temperatures.The results of the mechanical inoculation of CMV by the crude infectious sap to young carrots cultivated from seeds differentiated this...

Attempt at demonstrating the effect of a weak magnetic field onTaraxacum officinale

Josef Novák, Ladislav Válek

Biologia plantarum 7:469-471, 1965 | DOI: 10.1007/BF02920691

The exposure ofTaraxacum officinale L. at flowering time to a weak magnetic field resulted in (1) retarded opening and the closing of the inflorescence, (2) wilting and death after prolonged exposure. Controls were unchanged. Plants exposed to the effect of magnetic fields were degenerated in subsequent year.

The toxic effect of the cultivation medium of plants infected with tobacco mosaic virus

Věra Sosnová

Biologia plantarum 7:472-473, 1965 | DOI: 10.1007/BF02920692

Docent Rudolf Řetovský (1904-1964)

S. Prát, L. Černý, A. Prokop

Biologia plantarum 7:399, 1965 | DOI: 10.1007/BF02920684

RNDr Ivan HRŠEL, CSc. (1926-1965)

K. Beneš

Biologia plantarum 7:406, 1965 | DOI: 10.1007/BF02920685