Influence of light and darkness on the concentration of lactic, glycolic, succinic, malic and citric acid in pea plants

Jana Barthová, Sylva Leblová

Biologia plantarum 1969, 11:97-109 | DOI: 10.1007/BF02921728

Chromatographic separation of an extract of organic acids on a Dowex-l column in the formiate cycle was used to study the content of several organic acids in pea plants, cultivated either in light or in darkness. Concentration changes of the individual acids in the course of growth indicate that the citrate cycle is blocked in the cotyledons of plants grown in light in the period around the 15th day of growth, probably at the site of succinic dehydrogenase (succinic and lactic acids accumulate and the content of citric and malic acids is exhausted). There is no inhibition in the cotyledons of etiolated plants. In vegetative organs, the concentration...

Role of auxin in growth and differentiation Processes of isolated shoot tips of maizeZea mays L.

Dagmar Horáková, Z. Sladký

Biologia plantarum 1969, 11:110-118 | DOI: 10.1007/BF02921729

The following work deals with the role of auxin in growth and differentiation processes of isolated shoot tips ofZea mays L. It seems that an optimal auxin concentration is apparently a function of a photoperiod duration. In case of a short day the optimal concentration is approximately 5 mg/l and in case of a long day it represents 1 mg/l. The duration of photoperiod influences even the level of exogenous auxins in explants. The plants exposed to the short photoperiod contain more substances of stimulative character while the ones exposed to the long day possess inhibitive substances. Externally applied auxin takes part in differentiation processes,...

Water balance in leaf tissue

Jana Pospíšilová

Biologia plantarum 1969, 11:119 | DOI: 10.1007/BF02921730

Samples of the leaf tissue (14cm²) were placed in a plexiglass chamber which consisted of three parts. Water absorbed by the leaf tissue on one side of the sample was transported through the middle part of the sample to the opposite side and was transpirated there. The intensity of transpiration the intensity of water absorption and water saturation deficit (w.s.d.) were determined simultaneously in this tissue by gravimetry. Water balance was studied either in saturated samples of leaf tissue or in tissue where w.s.d. (10%, 20%, 30%, 40%) was established in advance. Although conditions for water absorption in leaf segments were optimal,...

Role of water transport in origin of water stress

Jana Pospíšilová

Biologia plantarum 1969, 11:130 | DOI: 10.1007/BF02921731

Intensity of transpiration, intensity of water absorption, water saturation deficit (w.s.d.) in different parts of samples and rate of water transport was investigated in samples from leaf tissue of fodder cabbage and banana-tree.
In all experiments (at initial w.s.d. 0% and 20%, in samples from upper, middle and lower leaves of fodder cabbage and from leaves of banana-tree) a distinct gradient of w.s.d. in the direction of transport of water was determined, therefore the limiting factor in the water balance was rate of water transport and not rate of water absorption.
The lowest amount of water was always transported within transpiring part...

Effect of trophic conditions on asparagine transamination in wheat plants

Alena Činčerová

Biologia plantarum 1969, 11:139 | DOI: 10.1007/BF02921732

In dialyzed extracts from winter wheat plants transamination reactions occurred between asparagine and α-ketoglutaric acid (L-asparagine+2-oxoacid=2-oxosuccinamate+ +amino acid; 2. 6. 1. 14). Reactions with pyruvate exhibited a very low activity. Besides transamination products,i. e. glutamate and alanine, aspartic acid was formed in both reactions. Deamidation was more intensive in the weak reaction asparagine-alanine and less intensive in the asparagine-glutamate reaction.
When calculated per dry weight unit the activity was the same in plants of all variants (three experimental variants-Knop, potassium humate, water). A higher, activity...

The dynamics of the accumulation of nitrogen, phosphorus and potassium in maize and peas in the first growth phases at constant mineral nutrition

J. Minář, Z. Laštůvka

Biologia plantarum 1969, 11:149 | DOI: 10.1007/BF02921733

The authors studied the growth intensity, the accumulation and distribution of nitrogen, phosphorus, and potassium in maize and pea plants under conditions of hydroponic culture. They found that RGR dropped by about 50% within 32 days of cultivation. The content (in mg/g dry weight) of nitrogen and potassium in maize, and of nitrogen and phosphorus in peas registered a substantial decrease, while the content of phosphorus in maize and that of potassium in peas exhibited a slight increase and a slight decrease towards the end of the experiments. The relative absorption rates of nitrogen and phosphorus in maize were maximum after 28 days of cultivation,...

Endogenous auxins in apical buds ofChenopodium rubrum L. after application of (2-chloroethyl) trimethylammonium chloride (CCC)

Lola Teltscherová

Biologia plantarum 1969, 11:158 | DOI: 10.1007/BF02921734

Apical buds ofChenopodium rubrum from plants treated with CCC contain more endogenous auxins than buds from control plants, the level of these compounds increasing with the application of rising concentrations of the retardant. An especially marked increase was observed in the level of substance "X" which on chromatographic separation runs in the zone of tryptamine or its derivative. Since it has been shown in previous experiments that the inhibitory effect of CCC on flowering ofChenopodium rubrum may be reversed by indole-3-acetic acid (IAA) it is believed that the increase in auxins after application of CCC does not concern biologically...

Floral morphogenesis and flowering in aseptic cultures ofBrowallia demissa L

P. S. Ganapathy

Biologia plantarum 1969, 11:165-174 | DOI: 10.1007/BF02921735

Floral buds ofBrowallia demissa, at three stages of development, were cultured on Nitsch and Nitsch basal medium. The supplements used include IAA; several cytokinins- benzyladenine, kinetin and 6-benzyl-9 tetrahydropyran-adenine (SD 8339); gibberellic acid (GA₃); 2, 3, 5-triiodobenzoic acid (TIBA); arginine and cysteine. All three stages of floral buds failed to complete development. In some treatments stages II and III produced callus and/or roots from the morphological basal end. Cytokinins promoted bud formation whereas both IAA and GA₃ depressed bud formation The shoots differentiatedin vitro were capable of...

Effects of shoot bending of apple trees on accumulation and translocation of¹⁴C-labelled assimilates

A. Mika

Biologia plantarum 1969, 11:175 | DOI: 10.1007/BF02921736

The translocation of¹⁴C-labelled assimilates from a single leaf in bent and intact apple shoots was studied in varying stages of shoot development. In actively growing shoots¹⁴C-labelled assimilates translocated from the treated leaf and accumulated mainly in the shoot apex. In moderately growing apple shoots radioactive assimilates were translocated from the treated leaf in both directions towards and down the shoot. In apple shoots showing only slight growth activity the¹⁴C-labelled assimilates were transported from the treated leaf mainly to the base of the shoot, stem and roots. Bending shoots changed the pattern...

Studies on soybean seed proteins by means of disc electrophoresis

Safonov V. I., Safonova M. P., Narbut N. A.

Biologia plantarum 1969, 11:183 | DOI: 10.1007/BF02921737

Three protein fractions (albumins, globulins and glutelins) of cotyledons of ripe and dormant soybean seeds were analysed by a modified polyacrylamide disc electrophoresis method. All fractions were shown to be multicomponent and easily characterized by their "protein electrophoresis spectra". A method of characterizing proteins by their relative electrophoretic mobility (R.E.M.) by comparison with a new nontoxic dye as a tracer is employed for a preliminary identification of proteins. Specificity of protein complement was investigated in view of the autors, further studies on dynamics of specific proteins in the course of ripening and germination...

Professor Otto Moritz

Biologia plantarum 1969, 11:N1 | DOI: 10.1007/BF02921738