The cytogenetic effect of thermal neutrons inLens esculenta (Moench)

J. Uhlík

Biologia plantarum 14:97-102, 1972 | DOI: 10.1007/BF02920952

The first information concerning the cytogenetic efficiency of thermal neutrons in lentil are presented in this paper. The range of cytologically effective dosages of thermal neutrons in lentil was determined. This determination enables us to compare the efficiency with the mutagenic effect of thermal neutrons and with their effect on the growth and development of plants of M₁ generation. These effects were already evaluated in previous communications.Thermal neutron irradiation significantly affected all the characters studied. A linear dependence of the effect on the dose of the neutron radiation was found for most of the analyzed...

Maize growth and ion absorption in Richter's solution at different flow rates

Radmila Macůrková, Z. Laštůvka

Biologia plantarum 14:103-111, 1972 | DOI: 10.1007/BF02920953

By comparing maize plants cultivated in standing nutrient solution with those from solutions flowing at different flow rates it has been established that absorption of nitrogen, potassium and especially of phosphorus was increased owing to the flow. There was likewise a relative rise in the distribution of nutrients to the overground parts of the plants. The content expressed per unit dry matter was increased only in the case of phosphorus; with nitrogen and potassium it was slightly lower than in the standing solution. Increasing amounts of iron were required under the conditions of flowing nutrient solutions to prevent chlorosis of the plants. The...

TMV-Infection syndromes in potato cultivars Erika and Krasava

Z. Polák, J. Limberk

Biologia plantarum 14:112-115, 1972 | DOI: 10.1007/BF02920954

Tre potato cultivars Erika and Krasava are unable to reproduce two strains of TMV systemically except when in graft symbiosis under normal greenhouse conditions with tomato which has been infected with the virus. The escape resistance of potato to TMV infection due to slight hypersensitivity was not changed either by long-lasting non-infectious symbiosis with TMV-sensitive tomato or in a constant environment (32±2 °C, 9 700 lx) which was adequate to change the hypersensitive reaction of some other TMV-hosts. On the contrary, enhanced temperature provoked a still more severe local and necrotic response in the potato varieties. This led to systemic...

The sorption surface of roots, as related to the fibrillar structure of cell walls

Maria Ryłko

Biologia plantarum 14:116-123, 1972 | DOI: 10.1007/BF02920955

The root surface determined microscopically amounts only to ten per cent of the surface assayed with methylene blue. This difference is assumed to correspond to the sorption surface of cell wall interfibrillar capillaries. The volume of these capillaries amounts to 0.1 per cent of the total volume of the organ only, but their surface far exceeds the external root surface. It is suggested that the interfibrillar capillaries of the epidermis cell walls constitute the main elements of the root sorption surface.

The effect of various levels of nitrogen, potassium and phosphorus on oxidation reduction potentials in barley

J. Benada, Marie Váňová

Biologia plantarum 14:124-132, 1972 | DOI: 10.1007/BF02920956

The effect of nutrient solutions with certain essential elements lacking, on oxidation reduction potential (RP) of the first leaf was examined in two cultivars of barley seedlings NO₃^- and K⁺ decreasedRP considerably, PO₄^3- did not. The effect of NO₃^- and K⁺ was dependent. on the illuminance. Under glasshouse conditions, the increased level of NO₃^- and K⁺ did not cause any change ofRP. In field conditions, the increased supply of nitrogen fertilizers resulted in a lowerRP in leaves at ear emergence and...

Tobacco mosaic virus reproduction in plants with an increased anthocyanin content induced by phosphorus deficiency

Věra Sosnová, Marie Ulrychová

Biologia plantarum 14:133-139, 1972 | DOI: 10.1007/BF02920957

Studying relationships between tobacco mosaic virus reproduction, anthocyanin biosynthesis and phosphorus content in cultivation medium, it was found thatMartin's (1958) finding of an indirect proportion between anthocyanin and virus synthesis is valid even under the complicated conditions of pathological anthocyanin formation induced by phosphorus deficiency. A decrease of anthocyanin biosynthesis with simultaneous stimulation of virus reproduction takes place at temperatures below 20°C. Increased anthocyanin biosynthesis accompanied with the inhibition of virus reproduction occurs at temperatures above 20°C. The obtained results suggest that enzyme...

The stimulatory effect of uracil and 5-bromouracil on the seed set inPapaver somniferum L.

Věra Balatková, J. Tupý

Biologia plantarum 14:140-145, 1972 | DOI: 10.1007/BF02920958

A study was made concerning the effect of the analogues of nucleic acid components upon the seed set inPapaver somniferum L. For the experiments flowers one day after anthesis were used, as the pollination taking place at this flower age had previously been found to be most efficient for the seed set. The solutions of analogues in a 10 per cent sucrose were applied by injecting them into the ovaries three hours prior to pollination. Damage to the ovary by the injection reduces the seed set by about two thirds.In comparison with control flowers, into which only a sucrose solution was injected, 5-bromouracil at a concentration of 5.2×10^-4...

Retarding effect of inhibitors of protein and RNA synthesis on chlorophyll and protein breakdown

J. S. Knypl, W. Mazurczyk

Biologia plantarum 14:146-154, 1972 | DOI: 10.1007/BF02920959

Cycloheximide, ethionine,p-fluorophenylalanine, 6-azauracil, 5-diazouracil and vanillin, applied at relatively high concentrations, retarded the yellowing of kale (Brassica oleracea L. var.acephala) leaf discs in darkness, and stimulated it in light. All the compounds inhibited protein synthesis and retarded protein breakdown. Cycloheximide,p-fluorophenylalanine, diazouracil and vanillin also inhibited the incorporation of uracil-¹⁴C into RNA of senescing discs. Abscisic acid and 2-chloroethylphosphonic acid accelerated yellowing both in darkness and in light and stimulated the protein breakdown in senescing discs.Abscisic...

Storage of ethyl methanesulphonate-treated barley seeds with 15 per cent moisture. Influence of treatment and washing conditions

T. Gichner, T. Omura

Biologia plantarum 14:155-163, 1972 | DOI: 10.1007/BF02920960

Barley seeds were treated with ethyl methanesulphonate (EMS), washed for 24 h, redried to 15 per cent moisture and stored at 25°C. The criteria used for expressing the effect of storage were chromosomal aberrations in root tips, M₁ germination, M₁ seedling height, M₁ survival and the frequency of M₂ chlorophyll mutants. The increase of the M₁ biological injury due to storage was not influenced:a) by applying EMS solutions at pH 2, pH 7 and pH 10,b) by lowering the EMS concentration and increasing the treatment time,c) by different variations of washing with water and by washings with...

Book reviews

Z. Šesták, Ingrid Tichá, J. Pospíšilová, Ingrid Tichá, J. Čatský

Biologia plantarum 14:173-176, 1972 | DOI: 10.1007/BF02920964

Substances with cytokinin activity extracted from growing apices of apple-tree shoots

A. Friedrich, Libuše Hejmová, L. Chvojka

Biologia plantarum 14:164-166, 1972 | DOI: 10.1007/BF02920961

The presence of native cytokinins was studied in growing apices of apple-tree annual shoots. During June the presence of two compounds showing cytokinin activity in biotest was observed and their R_F value was determined in three chromatographic systems.

A nicotinamide adenine dinucleotide phosphate phosphatase fromChlorella

R. Chopowick, G. F. Israelstam

Biologia plantarum 14:167-169, 1972 | DOI: 10.1007/BF02920962

A phosphatase enzyme hydrolysing NADP⁺ and NADPH to NAD⁺ and NADH was found to be present in extracts ofChlorella pyrenoidosa

Isoenzymes of lactate dehydrogenase in the root growth zones ofVicia faba L.

Věra Hadačová, Jiřina Švachulová

Biologia plantarum 14:170-172, 1972 | DOI: 10.1007/BF02920963

The present studies of the LDH isoenzymes have been made as a part of our studies on the respiration systems of the roots ofVicia faba. All the root zones had 5 LDH isoenzymes and 2 antibands, but there were differences in their relative quantity. Cathodic isoenzymes (LDH₅, LDH₄) prevailed in the meristematic zone, whereas the anodic ones (LDH₁) prevailed in the others. The different enzyme activity in individual zones is probably connected with the transition of the anaerobic metabolism in the meristem to the aerobic one in the differentiating parts of the root.