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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...
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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...
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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...
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Genetically modified plants for future of globally warmed planet
Nedělová, Jana ; Opatrný, Zdeněk (advisor) ; Nátr, Lubomír (referee)
Many problems which have an adverse impact on crops, come into the agriculture with global warming the planet and thus changes in regional temperature and humidity regimes. These problems will be significant especially in developing countries that are already interfered by drought and threatened by famine. Therefore major target is developing of plants resistant to these climatic changes. Only the very classical breeding doesn't clearly sufficient for these tasks. However, genetic engineering could contribute significantly by genetically modified (GM) plants. This modern breeding-cultivation technology has several advantages in comparison with traditional breeding. One of them is for example targeted and well-controlled change in genotype, which allows obtaining plants with specific desired properties.
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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...
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Inter- and intraspecific variability in Vicia faba L. and Zea mays L. response to water deficit
Fridrichová, Lenka ; Holá, Dana (advisor) ; Zelenková, Sylva (referee)
This work monitors the response of plants to water deficit and subsequent restoration of water availability with the aim to expand our knowledge about plant behaviour during and after drought stress from the perspective of two plant species with a different type of photosynthesis. A particular attention was paid to the intraspecific differences and their possible changes during stress and post-stress periods. The plant response was monitored as the changes of selected photosynthetic, morphological and developmental characteristics caused by the cessation of watering for six days followed by a six-day period of renewed optimal water supply. The experiments were carried out on plants with different types of photosynthesis - C3 plant Vicia faba L and C4 plant Zea mays L.; for both plant species, three varieties / genotypes were monitored. The response of both plant species to insufficient water supply differed by the extent of changes in relative water content (RWC), chlorophyll fluorescence parameters, the dry mass of individual leaves (developed during the stress period), the ratio between the aboveground dry mass and dry mass of roots. In drought-stressed plants, downward trend in RWC was observed, as well as the increase of the minimum yield of chlorophyll fluorescence in dark-adapted leaves (F ),...
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The influence of water stress on germination and growth of grasses and legumes
HRDA, Lukáš
The negative impact of climate change on agricultural production is consistently increasing all over the world. As a result of these changes, the yields of some crops have been decreasing. The main problems include frequent weather changes, especially long periods of drought accompanied by high temperatures. The aim of this diploma thesis was to assess the effect of water deficit on offshoot germination and longevity of selected species of grasses and clovers. The evaluation of resistance to water deficit was carried out using both laboratory and pot experiments. The results of these experiments were used to evaluate the drought resistance of the tested species of grasses and legumes. Based on the proven drought resistance, appropriate species and varieties have been recommended for cultivation in conditions of water deficit. The issue of drought resistance is to be paid more and more attention in the future. According to most forecasts, increasingly long periods of drought are likely to occur. For this reason, there will be the need for crops and varieties that best resist to various abiotic stresses.
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The influence of water stress on selected grass species and sward botanical composition
PAVELOVÁ, Lenka
The main goal of this thesis is to ascertain the influence of a water stress on regenerative and growth properties of grasses which were exposed to a water deficit and the influence on area composition of certain permanent grass vegetation. Assessment levels were based on container experiments. Each container contained selected class and subclass of a grass with different water regime demands. The aim of these experiments was to determine regenerative and growth abilities of chosen grasses which were exposed to water deficit and their ability to regenerate after drought during the grass branching phase. Another part of these experiments was to assess water regime impact on distribution of grasses in chosen areas. In the Czech Republic, grass vegetation is one of the basic food components for farm animals, mainly cattle, and it is an important landscaping element. It is also a component of forage industry which is a significant part of an agriculture output and the main goal in practice is to provide sufficient production of high quality,biologically valuable and healthy fodder.
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The influence of water deficiency on selected fodder crops
HRDA, Lukáš
The aim of this thesis was to assess the effect of the water deficit on selected species of perennial fodder crops ? grass and clover, as well as annual fodder crops, by comparing different species in conditions of changing climate and increasing extreme weather events, especially drought. Assesssment was based on comparing different literature and Internet data. Among the clover the following were evaluated as prospective for growing in dry weather - Onobrychis viciifolia, Lotus corniculatus, Medicago lupulina and Melilotus albus. Among the grass Festuca arundinacea and Bromus inermis proved to resist drought the best. Among the annual fodder crops Sorghum vulgare best resisted drought. In dry weather using grass and clover mixtures, which reach more balanced yields than some monocultures, proved to be more suitable. More attention should be paid to the issue of drought resistance because in the future such crops and species will be required that prove higher abiotic stress resistance, especially drought resistance.
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