National Repository of Grey Literature 28 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Using of Analytical Methods for Study of Adaptation Mechanisms of Festuca Rubra L. Plant
Paučová, Michaela ; Haisel, Daniel (advisor) ; Hnilička, František (referee)
Due to abiotic stress factors, such as excess of electromagnetic radiation, high and low temperature, drought, moisture or salinity, the reactive oxygen species (ROS) in living organisms which have a negative impact on the proper functioning of vital organs, metabolic pathways and ultimately, existence, are formed. In the case of a plant, this is in particular a limited activity of the photosynthetic apparatus which can lead to the death of the plant. All of analysis were preceded by the collection of Festuca rubra L. samples from different locations in the south-western part of Norway. The locations were different in their temperature (6,5; 9,5 and 10,5řC) and moisture (600, 1200, 2000 and 2700 mm). Then all samples were cultivated in four climaboxes where combinations of four "extreme" temperatures and moistures (moist/cold, moist/warm, dry/cold and dry/warm) were set. Experimentally this work was focused on the extraction of ascorbate peroxidase as an antioxidant enzyme, phenolic substances and plant pigments present in Red Fescue (Festuca rubra L.) as a model organism. The activity of ascorbate peroxidase was quantitatively determined by spectrophotometric reduction of nitrobluetetrazolium, the phenolic content was evaluated spectrophotometrically by the Folin-Ciocalteau reagent and the plant pigments...
Analysis of selected parameters inbred and hybrid maize stressed by flooding
Čečetka, Petr ; Kočová, Marie (advisor) ; Hnilička, František (referee)
Flooding is an important stress factor that influences the growth of plants and their production. Anthropogenic activity is causing gradual changes in the climate, consequently triggering changes in the distribution of precipitation. This leads to the conditions alternating between optimal, draughts, and excessive flooding that the plants have to cope with. The aim of my diploma thesis was to evaluate the consequences of flooding and the subsequent restoration of normal cultivating conditions of two inbred lines of maize (Zea mays L.) (2023 and CE704) and their reciprocal hybrids (2023xCE704, CE704x2023) that were exposed to the stress of flooding and subsequent restoration during several phases of their ontogenetic growth. For both the plants exposed to flooding and the subsequent restoration and the plants grown in optimal conditions only, there were several morphologic and physiological parameters, parameters related to the water status, and parameters that determine the extent of the damage done to the cellular structure or characterize the defense mechanisms employed by the plant in reaction to the stress. Flooding of the plants often led to an increase in their transpiration speed, stomatal conductivity, MDA and H2O2 contents, and catalase activity. For other parameters, the flooding usually...
The physiological and proteomic characterisation of winter oilseed rape upon abiotic stress
Urban, Milan ; Vítámvás, Pavel (advisor) ; Hnilička, František (referee) ; Valentová, Olga (referee)
- Ph.D. thesis - Milan Urban, 2017 In some years, the agricultural production of oilseed rape, an important crop in the Czech Republic, is - besides biotic stress - facing the problem of damage caused by frost or drought. Together with special attention paid to proteins revealing responses between crop genotypes with differential abiotic stress tolerance levels we reviewed possible applications of proteomic results in crop breeding programs aimed at an improvement of crop stress tolerance (paper 1). For first original result, cold temperature was imposed upon non-vernalized plants in the stage of leaf rosette. The article (paper 2) shows a significant correlation between frost tolerance (FT), dehydrin (DHN) accumulation, and photosynthetic acclimation in five cultivars (cvs). Newly, the specific DHN D97 was shown to accumulate and other DHNs were shown to have qualitative differences in accumulation. These results imply that proper FT assessment is based on rapid photosynthetic acclimation together with higher accumulation of protective compounds. Drought stress (paper 3) was imposed in the water- demanding stem prolongation phase before flowering, because late-spring drought before and during flowering decreases the yield and seed quality significantly. This paper newly describes two water-uptake...
Úloha brassinosteroidů v odpovědi různých genotypů kukuřice na změny v zásobování vodou.
Trubanová, Nina ; Rothová, Olga (advisor) ; Hnilička, František (referee)
Brassinosteroids (BRs) have been recognized to alleviate damages caused by drought stress and to enhance tolerance to water deficit. Soaking of maize kernels before the sowing in solution with different 24-epibrassinolide concentrations (especially the 10-8 M) had a positive effect on growth of plants before and after the stress period, although it did not affected relative water content and photosynthetic parameters. After the recovery under optimal conditions there were no differences among the treatments. When compared to spraying, soaking of maize kernels was not proved to have any advantages, though its positive effect on plants germination under water deficit conditions could be possible. Based on the results of the second season experiment it is not possible to deduce the role of exogenous BRs application (spraying with 24-epibrassinolide) or endogenous BRs biosynthesis (spraying with biosynthesis inhibitor - brassinazole) in maize plants subjected to water deficit. However, decrease in relative water content in contrast to chlorophylls content increase during the days following after drought stress onset in both cultivars (contrastive in drought sensitivity) challenges for further investigation of this problem. Understanding the role of BRs in plant drought tolerance and resistance is...
Response of different genotypes of Zea mays L. and Vicia faba L. treated with brassinosteroids to water deficit
Kuklíková, Radka ; Rothová, Olga (advisor) ; Hnilička, František (referee)
This work monitors the response of plants to the application of a solution of synthetic brassinosteroid (5-fluor-3α,17β-dihydroxy-5α-pregnan-6-on) under drought stress conditions and subsequent restoration of water availability. The response of two plant species was monitored under six-day period of cessation of watering and under six-day period of renewed optimal water supply. The experiments were carried out on plants with different type of photosynthesis - C3 plant Vicia faba L. and C4 plant Zea mays L.. For both plant species, three varieties/genotypes were used. Photosynthetic, morphological and developmental characteristics were monitored. The brassinosteroid treatment influenced more the morphological than the photosynthetic characteristics. The content of photosynthetic pigments was influenced more than the chlorophyll fluorescence parameters. The differences in morphological characteristics between individual varieties/genotypes were observed. The response to the application of brassinosteroid was observed especially for drought-sensitive variety/genotype. Application of brassinosteroid caused increase of the dry mass of leaves and roots, the height to leaf , the height of the whole plant and its increment under stress and post-stress periods in both plant species. The content of...
Effect of water deficit on the energy content of individual plant organs in selected species of leafy vegetables
Šimůnková, Petra ; Hnilička, František (advisor) ; Česká, Jana (referee)
This work presents the impact of water deficit on dry mass production and photosynthetic accumulation of energy on every single plant´s organs of selected plant species. As a chosen experimental material were taken plants of Spinacea oleracea "Matador" sort and Tetragonia tetragonioides. Spinacea oleracea and Tetragonia tetragonioides plants were grown in containers 11x11cm large in mixture of garden substrate A with silicon sand (2:1) in 2 variations placed in FAPPZ greenhouses. One variation was for control and second was exposed to stress reaction. Control variation had been watered for whole time of experiment with 50ml of water 2 times per week. Stressed one had been watered after puncturing and 6. taking until the end of experiment. During the plant´s ontogenetic evolution had been monitored dry mass´s weight on singular plant´s organs. With usage of burnt calorimetry method had been monitored capacity of photosynteticaly accumulated energy in dry mass. Quantity of netto energy had been found out by dry burning adiabatic calorimeter LAGEST MS 10A. From the gained results emerge, that plants of Tetragonia tetragonioides have 2 times higher weight growth apart from Spinacea oleracea. Control plants of Tetragonia tetragonioides have higher weight by 25,5% (123 mg) compared to the plants growing in water deficit. Likewise higher weight of roots had been observed on control plants (41 mg) compared to the stressed plants (40 g). Control spinach plants had higher weight of above-ground biomass by 19,5% compared to the stressed ones (43 mg). Roots of control plants had lower weight compared to stressed variant by 2960 mg. From the results emerge, that plants of Tetragonia tetragonioides have higher weight of roots dry mass and above-ground biomass compared to the Spinacea oleracea plants. Burning heat without ashes was on above-ground biomass of control plants Tetragonia tetragonioide on 15,96 kJ.g-1 level and on stressed plants 14,93 kJ.g-1 . In case of Spinacea oleracea plants was amount of control plants energy 14,98 kJ.g-1 and on stressed 14,21 kJ.g-1. Burnt heat without root ashes of Tetragonia tetragonioides control plants was higher by 1.11 kJ.g-1 then on stressed ones (13,19 kJ.g-1). In case of Spinacea oleracea plants was amount of roots energy on control plants 11,90 kJ.g-1 and on stressed 11,72 kJ.g-1 . Based on measurement were verified differences between species in reaction on water deficit and observed characteristic. From measuring emerged, that Spinacea oleracea plants are more sensitive on effect of water deficit compared to the Tetragonia tetragonioides plants, which is more tolerant. Next thing observed is, that there are differences in amount of dry mass and rate of burnt heat in relation on effect of water deficit.
Use of anti-stress agents to minimize the consequences of stressors on the production of Horticultural Crops
Nosálková, Monika ; Hnilička, František (advisor) ; Dana, Dana (referee)
The objective of the thesis is to research the physiological differences between picked genotypes of Capsicum annuum and the effect of lower temperatures in the beginning of ontogeny. Another objective is to find out how Capsicum annuum plants react to application of anti-stress agent Atonic and to determine the most appropriate physiological indicators of resistence to low temperatures. Capsicum annuum ranks among thermophilic crops for which the temperature optimum is of 22 - 25 °C during the day and 18 - 20 °C overnight. They are planted at the field station at the time when ground frost may occur. These can cause physiological changes in the plant or even cause her death. Three varieties were chosen for the experiment: Amy, Eva a Lydia. Plants were divided into a control group and treatment group. Both groups were further divided into two additional groups - with and without the application of Atonic in the beginning of vegetative growth (6th day of exposure to stress). Control group plants were grown at 20 °C and stressed plants were moved into a klimabox with temperature of 5 °C throughout the entire day. Such temperature may occur after planting the plants into an outdoor habitat. Proline content in leaves of Capsicum annuum and relative discharge of electrolyte was studied in two - day intervals. From the obtained results it can be concluded that the accumulation of proline was the highest for Lydia variety in a stressed scenario with the application of Atonic and the lowest proline content was found in in the Amy variety in a control group. Furthermore, it was discovered that the ontogeny of plants has an effect on the accumulation of proline and relative discharge of electrolyte from the beginning of the measurement. The absolute highest electrolyte discharge was measured in the Lydia variety in a stressed scenario and the lowest one was present in the Amy variety in a control group. These results confirm the hypothesis.

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