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Experimental cultivation systems in root system research
Střelec, Petr ; Soukup, Aleš (advisor) ; Lhotáková, Zuzana (referee)
The growing awareness of plant root importance has contributed to the continuous development of cultivation methods that facilitate more efficient and effective root research. Due to their sessile nature, plants rely extensively on roots for water and ion absorption (Meister et al., 2014). As a result, plant roots must adjust to an array of unfavorable conditions such as salinity, drought, and high temperatures. To better understand root response and promote agricultural development, researchers simulate various stressors in controlled conditions. More recently developed transparent soils and soilless cultures aim to overcome the limitations of traditional soil cultivation, which include imprecise variable control, heterogeneous conditions, and destructive root sampling (Gregory et al., 2009). When planning an experiment, it is crucial to select an appropriate cultivation method to ensure success. The aim of this thesis is to provide a comprehensive overview of the benefits and limitations of commonly used cultivations techniques in plant stress research. Transparent soil reliably mimics the mechanical properties of soil whilst allowing for easy root access and use of numerous visualization techniques. On the other hand, it still maintains the need for a larger cultivation area just like soil. The...
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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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Relationship between leaf biochemistry, physiology and specie's competitiveness in selected grasses of relict tundra in Krkonoše Mts.
Mamula, Petr Martin ; Lhotáková, Zuzana (advisor) ; Tylová, Edita (referee)
The Krkonoše (Giant Mountains) Arcto-Alpine Tundra is an area that is part of the Krkonoše National Park with a unique ecosystem and biodiversity. In history, this area was very fundamentally influenced by the intervention of man, who farmed here and thus caused the creation of today's rare matgrass (Nardus stricta L.) meadow ecosystem. Thanks to the low growth and sparse foliage of the matgrass, many other plant species grow in these matgrass meadows, which are often endemic and protected by the law. In recent years, however, the matgrass has been overgrown by other grasses, such as the hairy reed grass (Calamagrostis villosa J.F. Gmelin), which, due to its taller growth and dense canopy covering the surface, does not allow the growth of rare species such as matgrass. Therefore, the aim of this work was for matgrass (N. stricta) and three other selected species of grasses - tufted hair grass (Deschampsia cespitosa (L.) P. Beauv.), moor grass (Molinia caerulea (L.) Moench) and hairy reed grass (C. villosa), to identify, based on biochemical, structural and physiological foliar parameters, a parameter or a combination of parameters that could give competing fennel grasses a competitive advantage. Field research and collection of foliage samples, for subsequent laboratory processing, took place in...
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Adaptation of Plantago plants to environmental conditions: the role of carbohydrate balance
Skulníková, Barbora ; Konrádová, Hana (advisor) ; Lhotáková, Zuzana (referee)
Sorbitol is a linear sugar alcohol which is, together with sucrose, the primary photosynthetic product in the Plantaginaceae family. Sorbitol and sucrose are used for long-distance transport of photosynthetically fixed carbon via phloem. Many plant species accumulate sugar alcohols during drought or salt stresses, and it leads to higher tolerance to these stress conditions. The aim of this diploma thesis is to describe selected metabolic and structure differences with a focus on the sorbitol and sucrose balance, in two Plantago species - glycophytic Plantago lanceolata and halophytic Plantago maritima, which differ in life strategies. The plants were cultivated hydroponically in Araponics boxes. Previous results of our team show, that sorbitol accumulates in Plantago leaves up to ten-times higher concentrations compared with sucrose. This difference is deepened when the plants are exposed to salt stress. Sorbitol to sucrose ratios vary between vascular tissue and phloem sap. We assume that increased salt tolerance of P. maritima is based on the different distribution of assimilates through the plant, and by their partitioning between metabolic, storage and transport pools in mature leaf, which also manifests under non-stress conditions. In both genotypes, I compared growth rates under standard...
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The phenomenon of Foliar Water Uptake - mechanisms and consequences with a focus on temerate plant species
Oramová, Viktorie ; Lhotáková, Zuzana (advisor) ; Ponert, Jan (referee)
The ability of plants to absorb water through leaves has been a matter of the sientific discussion for a long time. Among the epiphytic species (tilandsies for example), reduced root system and foliar water uptake (FWU) is considered an adaptation for life in soil-less environment, and FWU is a necesssity. It was surprising, that the same ability has been discovered in plant species with normally developed root system. Over the time, new pieces of evidence about FWU in broad range of plant species has been published and FWU is getting universal for all plants, across the taxonomic groups or biomes, including temperate zone. The systematic focus on FWU and continuity of its research is lacking and therefore the knowledge about FWU is still only partial. This bachelor's thesis is focused on mechanisms of FWU and the leaf structures that may mediate it. The ability of water to pervade cuticle through aquatic pores is discussed, together with the possibility of water absorption by stomata, trichomes, hydathodes or epiphylic organisms. Another discussed topic is the use of this water by plant - improving of the water regime, refilling of the embolized xylem vessels, possible exudation by roots etc. The matter of FWU has other consequences on the ecosystem level, like in water cycle or the plant's...
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Determination of chlorophyll content in selected grass communities of Krkonoše tundra based on field spectroscopy and aerial hyperspectral data
Pinlová, Gabriela ; Červená, Lucie (advisor) ; Lhotáková, Zuzana (referee)
The thesis focuses on the determination of chlorophyll content from hyperspectral data in grass communities in the arctic-alpine tundra in the Krkonoše Mountains, namely Nardus stricta, Molinia caerulea, Calamagrostis villosa, and Deschampsia cespitosa. Leaf chlorophyll content (LCC) was measured using two methods - spectrophotometric destructive determination in the laboratory, and the LCC assessed non-destructively by fluorescence portable chlorophyll meter CCM-300. Leaf area index (LAI) values for canopy chlorophyll content (CCC) retrieval were also acquired by destructive biomass sampling and indirectly using LAI-2200C. Relationships were established between the LCCs, LAI, CCCs, and vegetation indices (VI) calculated from respective spectra, i.e. leaf level spectra acquired with contact probe coupled with an ASD FieldSpec4 Wide-Res spectroradiometer, canopy level spectra measured by the spectroradiometer and extracted from hyperspectral images (HSI) acquired by Headwall Nano- Hyperspec® mounted on the DJI Matrice 600 Pro drone. Chlorophyll content maps were created based on the results of multiple stepwise linear regression applied to HSI. For the model, derived from the non-destructive data sampling and used for the LCC map, a RMSE of 66.55 mg/m2 was achieved. Keywords: leaf chlorophyll...
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Water use efficiency (WUE), its definition and importance in plant resistance against osmotic stress
Jedlička, Tomáš ; Hála, Michal (advisor) ; Lhotáková, Zuzana (referee)
Water is one of the main limiting factors of plant growth. Availability of water on our planet is decreasing, and if we add fast-growing human population, we have a problem growing. Scientists from all around the world, especially those from arid regions, are facing a big problem, which is an attempt to make the most efficient use of water by plants. If this problem should be solved, we need to understand the issue of Water Use Efficiency (WUE). This paper attempts to summarize the current knowledge related to the issue of WUE, mainly focused on anatomical and physiological parameters control of WUE, which is focused primarily on the issue of evapotranspiration. Another part focuses on clarifying the issue of WUE at the gene level and the related biotech opportunities. At the end of the work are discussed possibilities of increasing WUE using irrigation techniques. Key words: water use efficiency, evaporation, transpiration, stoma, stomatal density, abscisic acid, ERECTA
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Photosynthetic parameters as secondary selection traits during plant breeding for salt stress tolerance
Hlavatá, Věra ; Kočová, Marie (advisor) ; Lhotáková, Zuzana (referee)
High salt concentration is important abiotic stress factor that negatively affect plant growth and development and finally also their yield. Increase of plant tolerance to this stress factor is thus one of the most important goals in breeding programmes, particularly in areas with saline environment. Various physiological traits have been suggested for the testing of plant tolerance to improved salinity. Photosynthetic parameters play undoubtedly the main role, because of their rapid response to stress conditions. Generally, photosynthetic rate, chlorophyll content and chlorophyll fluorescence belong to the photosynthetic parameters, that are usually recommended for the evaluation of stress tolerance. All of them were also used for study of salt tolerance in crop plants. The advantages of these measurements are rapidity, non-invasive techniques and particularly, the possibility to test wide collection of genotypes during the short period. Although some of the parameters were recommended for the evaluation of stress tolerance, the results are still ambiguous. The aim of this study was to briefly describe the changes of selected photosynthetic parameters of different plant species in consequence of salt stress and assess the usefulness of these parameters for reliable screening for salt tolerance.
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Hydraulic redistribution and within community plant relations
Lörinc, Filip ; Lhotáková, Zuzana (advisor) ; Tylová, Edita (referee)
Hydraulic redistribution is a widespread process of passive water transport through the plant root system along the gradient of water potential. This process significantly affects other plant belowground and aboveground processes. Water can be transported in several directions by hydraulic redistribution. The aim of the first part of this thesis is to summarize the knowledge about the operation of hydraulic redistribution. It describes the causes and consequences of the hydraulic redistribution as well as its main types. Subsequently, mainly vertical hydraulic redistribution is observed, the main components of which are the hydraulic lift and the hydraulic descent. The second part focuses on how vertical hydraulic redistribution can influence the interactions among plants and the functioning of the whole ecosystem. The answer to this question is sought in the savanna plant life, which is composed of scattered trees and their grassy understory. Savanna plants are exposed to dry and wet seasons, which creates a changing soil gradient of water potential throughout the year, which is of great interest for hydraulic redistribution research. This thesis shows that woody species have a competitive advantage over the grassy understory due to the presence of a hydraulic descent. Competition between trees...
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Study of Coniferous Needles in Relation to Environmental Factors Using Approaches of Quantitative Anatomy and Laboratory Spectroscopy
Lhotáková, Zuzana ; Albrechtová, Jana (advisor) ; Šantrůček, Jiří (referee) ; Lukac, Martin (referee)
SYNTHESIS - CONCLUSIONS: This thesis combines two methodical approaches at different hierarchical levels of plant ecophysiology, which both are applied in field research and bring new valuable information for comprehension of several aspects of carbon cycle in forest ecosystem, particularly coniferous. The quantitative anatomy represents the first approach. At the leaf level application of confocal microscopy on fresh and frozen-stored needles and subsequent stereological estimation of mesophyll geometrical parameters proved to be suitable and sensitive enough for estimation of changes in mesophyll after simulated acid rain or differentiation of sun and shade needle ecotype. Application of systematic uniform random sampling of sections along the needle axis revealed insight to heterogeneity of mesophyll geometrical parameters within the needle and confirmed representativeness of the sampling from the middle region of the spruce needles. The second approach, laboratory measurement of shoot reflectance, represents important step in verification of relationships between leaf biochemical and optical properties, which can be subsequently used for monitoring of forest health, foliar or soil chemistry using remote sensing techniques. At the level of Norway spruce crown, samples of even-aged needles from the upper...
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