Biologia plantarum, 1959 (vol. 1), issue 4
Article
The role played by growth in the determination of water deficit in plants
Jiøí Èatský
Biologia plantarum 1:277, 1959 | DOI: 10.1007/BF02920847
The aim of this work was to establish under what conditions the water deficit values obtained byStocker's (1929) method can be considered to be those for actual water deficits. It was found that the water intake of detached leaves is not necessarily due only to incomplete saturation of the leaf tissues with water, but that in young leaves it is caused to a great extent by their extension growth. Thus, water deficit in the sense ofStocker's definition is not merely a simple physiological state of incomplete saturation of the tissues, but is expressed by the sum of the need for water to achieve the greatest possible saturation of the tissues and the...
A method of storage of leaf samples for chlorophyll analysis
Zdenìk ©esták
Biologia plantarum 1:287, 1959 | DOI: 10.1007/BF02920848
In the course of experiments with leaf samples of pumpkin, sunflower, leafy fodder kale, sugar beet, tobacco, clover and begonia several, methods of storing material were compared with the object of determining the amount of chlorophyll (a+b) after 1 to 3 months. Chlorophyll analyses checked by paper chromatography provided evidence that the most reliable method of serial analyses is the following: Leaf discs are heated in very pure anhydrous acetone to its boiling point (with some MgCO3 present), rapidly closed with a paraffin stopper and then kept in the dark at temperatures just above 0°C. 50 leaf samples can thus be prepared for...
Peculiarities of the development of alternatives in relation to their winter-hardiness
A. K. Fedorov
Biologia plantarum 1:295-301, 1959 | DOI: 10.1007/BF02920849
Some peculiarities of the development of wheat alternatives causing their winter-hardiness were investigated.1. Prolonged vernalization of wheat alternatives (for at least 80 days) considerably accelerates their development after autumn sowing or after earlier sowing on an artificial short-day regime. Under these conditions the development of alternatives is normally slowed down considerably due to the short day. With rapidly developing vernalized alternatives the growing point is differentiated and shooting occurs in the autumn, which is reflected in the loss of their winter-hardiness.2. Continuous illumination similarly accelerates the development...
Increase of antiserum titres by means of immunization with plant-material precipitate-antigen
Evgenij Jermoljev, Jiøí Pozdìna
Biologia plantarum 1:302-309, 1959 | DOI: 10.1007/BF02920850
A description is presented of the principle of the method of increasing titres of antisera against phytopathogenic viruses, mycoses and bacterioses by immunizing with a precipitate-antigen according toDunin (1958). To a substrate containing viruses, bacteria or fungus spores, corresponding homologous antiserum prepared in advance is added to obtain a precipitate which is centrifuged and suspended in a small amount of physiological saline; this suspension (the precipitate-antigen) is used for immunization.The method was used for the preparation of some diagnostic antisera of plant virus diseases and bacterioses. Thus, the antiserum against yellows...
Modellstudien und Beobachtungen über die Gruppe der virösen Akarpien (Strolbur und Vergilbungen) anAnagallis arvensis L.
Ctibor Blattný
Biologia plantarum 1:310, 1959 | DOI: 10.1007/BF02920851
1. Anagallis arvensis L. (im weiterenA. a.) besitzt eine niedrige Keimfähigkeit, aber lässt sich leicht vegetativ vermehren und pfropfen. Beim Pfropfen "auf die Flasche" ist die Inkubationsdauer kurz, minimal bis 8 Tage. Die Pfropfung "übers Kreuz", das heisst das Durchziehen des abgeschnittenen kranken Stengels durch eine Längsöffnung im Stengel, der gepfropft wird, ist nur theoretisch von Bedeutung.2. Die Blüten gesunderA. a.-Exemplare schliessen sich bei Nacht. Die fransenförmigen Blüten bleiben länger geöffnet. Blüten mit reduzierten Blütenkronen besitzen nicht abfallende, Monate lang geöffnete Kronen. Bei uns beginntA....
Brief Communications
Problems of autosterility in Nicotiana alata Link et Otto (Formation of the inhibitory factor in the pistil)
Jarmila Tomková
Biologia plantarum 1:328-329, 1959 | DOI: 10.1007/BF02920852
From the partial results of artificial cultures in the presence of pistil tissue-pulp the author draws the preliminary conclusion that the inhibitory factor in the pistil ofNicotiana alataLink etOtto is already present before pollination.These questions were investigated by means of artificial cultivation of pollen tubes on agar in the presence of compatible and incompatible pulped pistils which had been previously prepared in various ways.This report gives the results of the last series of experiments (part A in the scheme). In the series of earlier experiments no signs of any marked inhibition were recorded.
Transmission of beet mosaic virus by the green peach aphid starved before infection feeding under different conditions of air humidity
Jaroslav Brèák
Biologia plantarum 1:330-332, 1959 | DOI: 10.1007/BF02920853
Aphids (Myzodes persicae Sulz.) were subjected to infection feeding after starvation for two hours, in varying air humidities. Infection feeding lasted for five minutes. The aphids which were starved under conditions of 0%, 34% and 56% air humidities transmitted the virus to a greater extent than those kept at humidities of 80% and 100%. (At the relative humidity of 0% there was a slight decrease of infectivity, probably due to reduced activity of the aphids). The phenomenon may be explained by the fact than when denied food in a dry atmosphere the aphids lose more water than in a humid atmosphere and hence their rate of feeding when on the...