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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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Odrůdová variabilita vitality osiva máku a její souvislost s velikostí kořenového systému
Jedličková, Žaneta
The thesis deals with seed vigour testing of 10 selected poppy genotypes. The aim was to determine the tolerance of poppy seed to selected suboptimal abiotic factors such as drought and temperature, and to clarify its relationship with the ability to form the root system or the final product - poppy seed in the yield-forming process. The laboratory part of the experiment was carried out at the Department of Crop Science, Breeding and Plant Medicine at Mendel University in Brno. Observations and measurements were carried out in a field experiment in the municipality of Chvalíkovice in 2022 under the direction of OSEVA PRO s.r.o. The results confirmed the expectation that the number of germinated individuals decreased with increasing drought intensity. Significant differences between genotypes were found when testing for vigour. Differences in root system size and seed yield were also found. An interesting finding of this work was the data showing a higher number of germinated individuals at 10 °C compared to testing at 20 °C. A statistically significant relationship was found when poppy seed vigour data were correlated with poppy root system size. The more vigorous the seed, the more able the plant is to form a robust root system in the early stages of growth. However, this relationship is no longer clearly reflected in the yield of poppy. There is no conclusive relationship between the vigour of poppy seed and its subsequent seed yield. A myriad of external factors enter into the poppy seed yield process, so it cannot be said that a highly vigorous seed will produce a large quantity of quality poppy seed.
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Vitalita a růst smrku ztepilého ve vertikálním gradientu České republiky
Kovačević, Vuk
Long periods of drought and irregular precipitation are common phenomena in the 21st century, which, along with the management of Norway spruce (Picea abies (L.) Karst.) outside its natural range in Europe, have led to the physiological decline and mortality of entire spruce stands. Drought significantly impacts tree growth and vitality, and these adverse effects are better monitored through tree water deficit (TWD) or water content in the tree. This study focuses on monitoring and analyzing the correlation between radial stem growth and climate changes at altitudes ranging from 380 to 972 meters in the Czech Republic. Growth was monitored using automatic dendrometers for five years (2016–2020). The negative impact of climate changes on radial growth is more significant at lower elevations below 650 meters above sea level, where the highest TWD occurred. This means that managing Norway spruce at lower elevations is risky and requires a change in management practices.
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Vliv smíšení porostu na dynamiku růstu borovice lesní (Pinus sylvestris L.) ve Finsku
Vyčítalová, Hana
Mixed stands excel in their species richness and they theoretically have a better precondition for coping with disturbances than monocultures. On the other hand, there is interspecies competition, which may result in the oppression of individual species in the ecosystem. A total of 12 research plots in the province of North Karelia (Finland) were selected to approximate the effect of forest mixing on the growth of Scots pine (Pinus sylvestris L.). In growing season 2018, stem volume changes and drought stress responses were observed in monocultures and with the admixture of one or both of the species Norway spruce (Picea abies L.) and Silver birch (Betula pendula Roth.). The measurement of volume changes was performed using point dendrometers installed on individual pines, the temperature and soil moisture were monitored by a TMS-4 sensor located in the soil in the middle of each research area. It was found that in all cases, Scots pine grew only in dependence on rainwater, not groundwater. It was discovered that individuals in monoculture grew up to twice as much as in both types of mixed stands. They also showed a better ability to saturate the tissues with water after it had been spent for transpiration during the July drought. In August, however, the response to drought stress was comparable in monocultures and mixed stands. The measured results show that interspecific competition may have a negative effect on the growth and drought tolerance of Scots pine in the short term. However, at a time of escalating extreme climate events around the world, this issue needs to be further explored in order to create optimal conditions for the growth of future forests.
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Assessment of drought response in local Scots pine ecotypes using anatomical, biochemical, and fluorescence stress markers.
Štěpánová, Kristýna ; Lhotáková, Zuzana (advisor) ; Stejskal, Jan (referee)
Global climate change and associated global warming is already a problem for temperate forest ecosystems and will continue to exacerbate the problem in the coming decades. Many species will have to adapt to a multifactorial combination of stresses, with increases in average air temperature, frequency and intensity of precipitation increasing drought episodes and drought-affected areas will enlarge. It is necessary to find ways to help the landscape cope with these intensifying phenomena. The possibility of planting suitable tree species that can manage water efficiently and survive even in periods of intense water scarcity is an option. The drought tolerance of trees is related to their phenotypic plasticity and ecotypic differentiation. Scots pine (Pinus sylvestris L.) is characterised by modest ecological demands on the environment and climate of the habitat, is phenotypically plastic and relatively drought resistant. The objectives of this study were 1) to evaluate and compare the response of different Scots pine ecotypes to drought stress due to reduced water availability using anatomical, biochemical, and fluorescence indicators of physiological status, and 2) to determine the biochemical phenotype of selected genotypes within a local Scots pine ecotype in a seed orchard in terms of...
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Effect of year on field germinability of opium poppy seeds
JELÍNKOVÁ, Olga
The aim of this thesis was to perform an experiment with opium poppy control and drought stressed plants. Gained seeds were tested for germinability in normal conditions and during simulated drought stress induced with PEG 6000. It was found plants for seed production provides less seeds with lower quality, but the vigour and germinability of these seeds are better. In this thesis I also tested the method of surface plasmon resonance as potentialy suitable method for dehydrin accumulation analysis. I managed to verify method for termostable proteins isolation and at the same time I confirmed, the SPR method is potentially usefull method for dehydrin accumulation analysis in opium poppy seedling plants.
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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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Vliv vysychání sadebního materiálu buku lesního a smrku ztepilého na jeho ujímavost a růst po výsadbě
Rašková, Pavlína
This bachelor thesis focuses on bad handling of bare-rooted and containerized seedlings of European beech (Fagus sylvatica L.) and Norway spruce (Picea abies L.). The aim of this thesis was to find out what influence the different length of drying of the root system of used planting material before planting, its follow-up and growth after planting and to determine critical values and times when plants are able to accept drought stress without significant losses and degradation of growth. The plants were planted as a freshly plants and after 1 and 2 weeks of establishment. The stress by drought was taking place in the shade, near the planting site for 0 to 48 hours. Along with planting, plants were tested to determine the water content of the root system or rootballs. The tested methods were the weight loss of the fine roots under constant heat stress, the measurement of the weight loss of the rootballs and the measurement moisture of the rootballs, using WHT 860, SM 300 and EMS sensors. The EMS sensor was found to be unpromising due to the inability to measure values in plants with too-dried rootballs whose plants did not show significant losses or degradation at the end of the growing season. Furthermore, it has been found that the seedlings of European beech are more predisposed to stress by drought, especially if the plants have before planting badly morphological conditions. On the contrary, the seedlings of Norway spruce are resistant to long-term stress.
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Analýza tvorby buněk sekundárního xylému a floému borovice lesní (Pinus sylvestris L.) v reakci na stres suchem
Fajstavr, Marek
Scots pine (Pinus sylvestris L.) is a long-term economically preferred woody species not only from the standpoint of its wood production but also thanks to its tolerance to extreme climatic factors, environmental modesty, and resistance to drought stress. In recent years, however, due to the action of the changing climatic conditions, this economically significant woody species withers. Its increment in the natural ecotype is affected by the adaptability to the increasing intensity of temperature extremes (prolonged heat waves). The combination of the lack of precipitation and extremely high air temperatures (even in the spring season) will significantly affect the resistance of this woody species to drought stress. This thesis is focused on the analysis of the secondary xylem and phloem cells formation of Scots pine depending on the physiological and morphological changes due to the affecting drought stress. Within the scope of the forming radial cells in individual growing seasons (2013–2016), it has been evaluated how the synergy of the specific factors affecting the overall anatomic structure of the annual ring and the vitality of the examined woody species was expressed in the formation, differentiation, and overall structure of the cells. During the four growing seasons (2013–2016), micro-cores (diameter 1.8 mm) were taken in weekly intervals in the research area in Sobesice of xylem and phloem (including the cambial zone) using the Trephor increment borer. From these micro-cores, permanent microscopic slides of the cross-section were made, on which the analysis of the cambial activity, cell formation, cell differentiation with time, and the evaluation of the morphometric parameters of the formed of xylem and phloem cells were performed. It was found that in each monitored growing season, the drought stress has shown, which was reflected by the dropped of the soil water potential (below -1 MPa) and the intensity of transpiration, which led to the stress reaction of the cambium. The reaction of the drought-stressed cambial zone has been expressed by the decreased activity (a sudden drop of the number of dividing cells) and subsequently, during the recurrence of precipitation, by the reactivation when an increase of the number of dividing cells was observed again. This factor initiated the formation of the intra-annual density fluctuations (IADF), i.e. the formation of the so-called false annual ring. The sensitive reaction of the cambium to the drought stress affected the cell production time, the number of formed cells, and also the time of differentiation of individual tracheids, which was expressed by the reduction of the radial dimensions and cell wall thickness of the tracheids. The artificially induced stress by stem girdling intensified the concurrent drought factor and in the area below the girdling, the cambial activity has stopped within two weeks after the performed treatment. The formed cells were not fully differentiated, so the zone of typically thick-walled cells of latewood was missing in the annual ring. The following growing season, the radial increment was only formed in the area above the girdling (without the latewood zone) and in the second half of the growing season, the trees gradually died. The activity of the plant hormone IAA was also affected by the drought in the summer season, when its concentration dropped below the measurability threshold (2 µg sample-1). At the time of the IAA concentration drop, latewood tracheids began to form and the phloem cell formation was completed. The synthesis and activity of the soluble low-molecular carbohydrates correlated with the course of the cambial activity and the cell differentiation phases, where the dynamics of the concentration also matched the timing of the formation of the individual cell formation phases. With phloem cells, a significant variability in the morphological dimensions has not been observed compared to xylem cells. The phenology of the needles indicated the cell wall formation phases and the initiation of the latewood tracheids. Due to the fact that the needles were fully formed in the season of the spring tracheids formation, their phenology did not reflect the drought stress which was recorded mainly in the summer season. Also, the increment of phloem was formed in the spring season. It has been presented for a long time that coniferous woody species react to the drought stress by thicker cell walls formation of the latewood tracheids. However, it has been observed within the scope of the research of this thesis that the water deficit affected the cambial activity, which has expressed itself on the intensity of the cell formation and the time of their differentiation. Due to this process, tracheids with smaller radial dimensions and a narrower cell wall were formed. This gradually causes structural changes of the formed annual ring, where the typically earlywood and latewood tracheids (classified according to radial dimensions and thicknesses of cell walls) may form independently on the growth seasonality. Especially in cases of IADF formation or in combination with the case where latewood is not even formed, a problem with the validity of the classification according to the so-called Mork’s criterion begins to occur. The understanding of the effect of the specific metabolic and physiological changes on xylem and phloem formation of Scots pine helps to clarify the issues of forestation and overall wood production of this economically significant woody species.
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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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