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Study of common bean drought response with the use of leaf optical properties
Svitáková, Lenka ; Lhotáková, Zuzana (advisor) ; Zámečník, Jiří (referee)
The negative effects of climate change have affected the conditions of agriculture areas, which leads to hampered cultivation of crops, including the common bean's cultivation. Changes, such as extreme temperature swings and lowered water availability in soil create a big challenge for today's agriculture in seeking solutions for safeguarding the food security for all people on our planet. The aim of this thesis was to study a wider range of genotypes of common bean to quantify their resistance against lowered water availability in soil, and to establish new approaches for detecting drought stress with the use of leaf optical properties. From the methodological point of view, this thesis connects the leaf optical properties with anatomical and biophysical leaf traits. The common bean (Phaseolus vulgaris) and the tepary bean (Phaseolus acutifolius) were employed as the model organisms. Plants were cultivated in two differing environments - in a greenhouse setting at the Faculty of Science of the Charles University in Prague and on the experimental fields in Colombia at the international research institute for tropical agriculture - Alliance of Biodiversity International and CIAT. There were 48 genotypes included into the field experiments in Colombia. These included genotypes from both Mesoamerican...
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Yield formation parameters of winter wheat under two CO2 levels in water sufficient and depleted environment
Hlaváčová, Marcela ; Klem, Karel ; Veselá, Barbora ; Findurová, Hana ; Hlavinka, Petr ; Smutná, P. ; Horáková, V. ; Škarpa, P. ; Trnka, Miroslav
Agricultural production faces with ongoing climate that in Europe takes form of changing seasonal precipitation pattern with more frequent drought spells. These changes come on top of rising air temperature and did and will affect productivity as well as onset and duration of key developmental stages for yield formation of major staple crops such as wheat. In order to ensure stable agricultural production and satisfy demand of the increasing humanpopulation, it is crucial to know responses of major field crops to these abiotic stress factors to assess suitability of genotypes to specific environmental conditions. The aim of this study was to evaluate final yield formation parameters of five winter wheat genotypes cultivated in pots and exposed to two different levels of CO2 concentrations (400 ppm as ambient and 700 ppm as elevated CO2 concentrations) and two water treatments (well- watered control and drought-stressed plants). Theexperimental treatments were set up in growth chambers from the end of heading stage (BBCH 59)to the beginning of ripening stage (BBCH 71) to simulate the conditions under future climate. The results showed that elevated CO2 concentration led to: (1) mitigation of reduction in final yield formation parameters of drought-stressed plants compared to those of control, (2) enhanced results of drought-stressed treatments compared to those of drought-stressed treatments exposed to the ambient CO2 concentration. Pannonia NS was found out as the less responsive genotype to the exposition of CO2 concentration (no statistically significant differences among ambient and elevated CO2 concentrations in all yield formation parameters were identified). On contrary, harvest index of genotype Bohemia was identified as the most sensitive parameter in response to drought stress as well as to the atmospheric CO2 concentration.
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Role of brassinosteroids in plant response to drought stress
Trubanová, Nina ; Rothová, Olga (advisor) ; Urban, Milan (referee)
Brassinosteroids are steroid phytohormones with a wide range of effects. They improve survivance of plants exposed to drought stress, increase their resistence and yield therethrough. They regulate the response of plants directly (via synthesis of metabolits) and/or indirectly (via the induction of antioxidant compounds and enzymes), often in interaction with other phytohormones. Experiments studying influence of brassinosteroids on response of plants stressed with water deficit differ in several parameters. Their correct interpretation is complicated conseguently.
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Effect of exogenous application of growth regulators on the physiological parameters and the yield of winter wheat under drought stress
Barányiová, I. ; Klem, Karel ; Křen, J.
The field trial aimed to evaluate the effect of different growth regulators in winter wheat under growth stress was conducted in 2013/2014. Within this experiment following growth regulators and fungicide with growth regulation effect were used: Retacel extra R68 (chlormequat chloride 720 g/l), Moddus (trinexapac-ethyl 250 g/l), Cerone (ethephon 480 g/l), Amistar (strobulirin 250 g/l). These growth regulators were applied at growth stages between BBCH 31 and BBCH 59. The aim of the experiment was to determine the impact of these regulators on the growth, development and yield of winter wheat when simulating the drought stress using experimental rain-out shelters. The attention was paid to assess the effect of exogenous application of growth regulators on the physiology and the yield of selected varieties of winter wheat under drought stress. From our preliminary results it can be concluded that almost all growth regulators increase the rate of CO2 assimilation and the stomatal conductance. Definitely positive effect on water use efficiency was found in fungicide treatment with growth regulation effect azoxystrobin. Under drought stress the decrease of chlorophyll content in leaves was found. Growth regulators CCC and trinexapac mitigate the decline of chlorophyll content caused by drought in the upper leaves but rather increased the impact in older (lower) leaves. Fungicide azoxystrobin alleviates the decrease of chlorophyll caused by drought in all leaves. The results show that all regulators increased yield, which demonstrate a positive effect under dry conditions because the vegetation season was very dry and lodging did not occur. Furthermore, the most pronounced mitigation of drought stress was found for strobilurin and partly also trinexapac. Results of field experiments can contribute to mitigating the impact of drought on yield formation and quality of winter wheat production in the realization of biological potential of wheat genotypes.
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Molecular detection of genes involved in drought stress reaction in opium poppy
ŠEFČÍKOVÁ, Miroslava
Drought belongs among one of the main abiotic factors that influence the yield and quality of agricultural crops. However, plants fight these negative environmental impacts by mechanisms developed during evolution. One of these mechanisms is the plants´ response on molecular level, which is gene expression. These genes potentially reacting to drought include the following genes: MLP43 and SDD1. For the purposes of molecular detection of these genes, the DNA from opium poppy plants (Papaver somniferum L.) Orel and Onyx type, was necessary to be isolated. Further, primer sets for the genes of MLP43 and SDD1 were designed. The chosen primer sets were used for analysis purposes using the real-time PCR method. The PCR method was also optimized.
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Impact of nitrogen fertilization and drought on glutenins content in winter wheat
Vostrejš, Pavel ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
In this bachelor thesis the effects of nitrogen fertilization and drought stress on glutenin fraction of winter wheat (Triticum aestitivum L.) were studied. Winter wheat cultivar Tiguan was grown under different rainfall mode, on the one hand in drought (DRY), on the other hand in normal downfall (WET). Part of the samples was treated with nitrogen fertilization at a dose of 140 kg / ha (N140), the other part remained without fertilization (N0). After the gliadins were separated, the glutenins from the samples were extracted with 50% isopropanol with 1% DTT. Individual glutenin fractions were separated by SDS-PAGE and quantified by computer densitometry. The drought did not have a statistically significant effect on any of the glutenin subunits. Nitrogen fertilization caused an increase in the total amount of glutenin as well as the amount of individual subunits. Interaction of water regime treatment and fertilization has not led to an increase in glutenin levels in HMW 3 GS and LMW 5 GS in DRY conditions.
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Effect of artificially induced drought on growth and productivity of selected crops within field experiment in Bohemian-Moravian highlands
Wimmerová, Markéta ; Hlavinka, Petr ; Trnka, Miroslav ; Žalud, Zdeněk ; Pohanková, Eva
The field experiments based on manipulating the crop environment are critical for determining the crop’s response to the climatic conditions expected in the future. An experimental site in Domanínek is located by 49°31'42 N, 16°14'13 E at an altitude of 560 m (potato production area). The field experiment using rain-out shelters for soil water availability reduction was conducted in 2015/2016. The main aim of this study was to assess the impacts of different water availability (rain-out shelters vs. control) on the performance of selected field crops (spring barley, winter wheat, winter rape and silage maize). Reduction of precipitation in treatment with rain-out shelters was confirmed by measuring soil water content. The amount of precipitation during growing period was reduced by 251 mm, 277 mm, 217 mm and 240 mm for the spring barley, winter wheat, winter rape and silage maize, respectively. As a consequence, leaf area index and yields declined, however the crop responses were not consistent.
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Water-use efficiency of winter wheat under heat and drought stress
Hlaváčová, Marcela ; Klem, Karel ; Novotná, Kateřina ; Rapantová, Barbora ; Urban, Otmar ; Hlavinka, Petr ; Smutná, P. ; Horáková, V. ; Škarpa, P. ; Trnka, Miroslav
Because such extreme weather events as dry spells and heat waves are expected to occur more frequently\ndue to climate change, the issue of appropriate water management for sustainable agricultural production\nis increasingly important. This study focuses on wheat, the second most widely grown cereal in the world\nand the most common cereal in European countries. The study assesses the effects of short periods (3 and\n7 days) of high temperatures (26°C as a control, 32°C, 35°C, and 38°C as daily temperature maxima from\n12:00 to 14:00) and drought stress at different developmental stages (DC 31 – beginning of stem elongation,\nDC 61 – flowering, and DC 75 – early grain filling) on water-use efficiency (WUE) in winter wheat\ncultivar Tobak. This cultivar is one of the most widespread winter wheat cultivars in Czech Republic fields.\nThe analysis of WUE showed that the cv. Tobak plants were able to withstand drought stress conditions\nthrough increased WUE. In contrast, wheat plants were stressed more markedly if exposed to higher temperatures\nand drought in combination. Generally, the wheat plants were most sensitive to drought at DC\n31.
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Impact of nitrogen fertilization and drought on gliadins content in winter wheat
Odstrčilová, Eva ; Obruča, Stanislav (referee) ; Hrstka, Miroslav (advisor)
In this diploma thesis the impacts of both nitrogen fertilization and drought on the content of proteins of the gliadin fraction in case of a winter wheat variety Tiguan were observed. Selected samples were cultivated at two locations in a total duration of two years. Two different conditions were selected: one without the nitrogen fertilization (0 kg N/ ha) and the other with the nitrogen fertilization in 140 kg N/ ha concentration. Second observed factor was the drought which was ensured by roofs above the crops and their cultivation in common climatic environment. Gliadin fraction was separated by the A-PAGE method and the protein quantification carried out by a computer densitometry. Such nitrogen fertilization caused a significant increase of gliadins, especially -1,2 and -5 fractions. Stress induced by the drought caused an increase of gliadin content compared to the control sample, particularly in case of - and - fractions. The most important factor influencing the gliadin content in grains was therefore the nitrogen fertilization in a dry environment. The observed increase of gliadin content was lower in case of the sample which was fertilized in a humid environment than in case of the sample which was fertilized in the dry one.
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Role of brassinosteroids in plant response to drought stress
Trubanová, Nina ; Rothová, Olga (advisor) ; Urban, Milan (referee)
Brassinosteroids are steroid phytohormones with a wide range of effects. They improve survivance of plants exposed to drought stress, increase their resistence and yield therethrough. They regulate the response of plants directly (via synthesis of metabolits) and/or indirectly (via the induction of antioxidant compounds and enzymes), often in interaction with other phytohormones. Experiments studying influence of brassinosteroids on response of plants stressed with water deficit differ in several parameters. Their correct interpretation is complicated conseguently.
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