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Influence of different tillage technology on the occurrence of weed species in cereals
JANUROVÁ, Eliška
The bachelor's thesis deals with the action of herbicides in terms of weed control in winter wheat. This is especially the occurrence of annual dicotyledonous weeds, herbaceous and perennial weed species. Of the selected herbicides, the best efficacy was found for the herbicide Mustang Forte in the conventional farming system and lower efficacy for Biathlon 4D when evaluated in a minimized mode of farming. The greatest herbicidal effect was recorded by Biathlon 4D against chamomile weeds.
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Vliv metazachloru a jeho metabolitu metazachloru OA na raná vývojová stádia raka mramorovaného
ZÁVORKA, Milan
Metazachlor is a selective herbicide used for controlling monocotyledonous and dicotyledonous weeds in oilseed rape and other cruciferous plants. It is mainly used as a pre-emergence herbicide. Metazachlor OA is one of the major degradation products of metazachlor. The aim of this study was to evaluate the effect of metazachlor and its major metabolite metazachlor OA on the early live stages of marbled crayfish (Procambarus virginalis). The effect of metazachlor and metazachlor OA was evaluated on the basis of behaviour, growth, biomarker of oxidative stress, antioxidant biomarkers, ontogenetic development and occurrence of morphological anomalies. The toxicity test was performed at five concentrations, two concentrations of metazachlor (3.2 micrograms/l and 22 micrograms/l) and two concentrations of metazachlor OA (3.2 micrograms/l and 22 micrograms/l) and one control (C). The test exposure was 40 days under defined laboratory conditions. The exposure of metazachlor and metazachlor OA at all tested concentrations caused statistically significantly higher mortality, delayed ontogenetic development and slower growth of crayfish. Metazachlor exposure in concentration 22 micrograms/l and metazachlor OA in concentrations 3.2 micrograms/l and 22 micrograms/l caused statistically significant reduction of antioxidant enzymes (SOD, CAT, GR, GST and GSH) levels in whole-body crayfish homogenate. Metazachlor OA showed a more pronounced adverse effect on the early live stages of marbled crayfish than its parent compound, metazachlor. Based on the results of this study we can point out the suitability of crayfish, especially their early live stages for toxicity tests and the possibilities of their use for biomonitoring of aquatic environment herbicides and their metabolites.
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Burrowing behaviour in crayfish
GUO, Wei
This PhD thesis is devoted to exploring the unresolved ecological gaps in freshwater crayfish burrowing behaviour from three parts, which are: a) the extreme weather conditions like drought; b) aquatic contamination; c) interspecific interactions. The first chapter of the thesis deals with the introduction of the basic information and background related to the burrowing behaviour of freshwater crayfish. The unresolved ecological gaps related to freshwater crayfish burrowing behaviour are: a) the potential effects of drought on crayfish reproduction; b) effects of aquatic contamination on the freshwater crayfish burrowing behaviour; c) crayfish competition for shelter as a primary resource. The second chapter explores whether embryogenesis or postembryonic development of freshwater crayfish can occur without free standing water inside the burrow. To address this question, three experiments were conducted using artificial burrows with high air humidity and using marbled crayfish (Procambarus virginalis Lyko, 2017) as a model species. We found that the ability of marbled crayfish to undergo terminal phases of embryogenesis, including hatching, as well as early postembryonic development under high air humidity conditions only. Postembryonic development was suspended in the absence of free water, and successfully resumed when re-immersed. This similar ability to tolerate drought-like conditions during postembryonic development may also occur in other crayfish species, especially primary burrowers. The third and fourth chapters covers the effects of water contamination on crayfish (red swamp crayfish Procambarus clarkii as model species) burrowing behaviour. We tested the hypothesis that burrowing behaviour of the red swamp crayfish would be altered with exposure to PhACs and herbicides at concentrations frequently detected in aquatic environments. As representative PhACs, we chose methamphetamine (METH) and tramadol (TRA) (1 ?g/L) (Chapters 3), and, as herbicides, terbuthylazine (TERB) and metazachlor (META) (2 ?g/L) (Chapters 4). We reported for the first time that depth and volume of burrows constructed by methamphetamine-exposed females was significantly lower than of unexposed controls. Tramadol-exposed females consistently exhibited a tendency to excavate smaller burrows compared with controls, although this was not significant (Chapter 3). Impact of herbicides on burrowing behaviour was less clearly manifested, although male crayfish exposed to META constructed a significantly higher number of burrows than did other groups (Chapter 4). The fifth and sixth chapters describe aggression of marbled crayfish during interspecific interactions under laboratory conditions was quantified by characterizing their direct agonistic interactions and competition for shelter with calico crayfish Faxonius immunis and spiny-cheek crayfish Faxonius limosus. Differences in aggression may predict interactions and outcomes under natural conditions. We found marbled crayfish to dominate size-matched calico crayfish (Chapter 5) and spiny-cheek crayfish (Chapter 6) in agonistic encounters. The higher activity and aggressiveness of marbled crayfish could facilitate displacement of other non-indigenous crayfish species either by direct interaction or through competition for resources such as shelter and food. The seventh chapter of the thesis presents the general discussion and summary obtained by the five chapters mentioned above. These data represent basic scientific information valuable for practical application. The outcomes of interactions among crayfish under laboratory conditions can be critical to evaluating over-invaded communities and ecosystems harbouring invasive species that share similar life histories, niche preference, and adaptation strategies.
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Ecotoxicity of herbicidal ionic liquids
Müllerová, Tereza ; Cajthaml, Tomáš (advisor) ; Klusoň, Petr (referee)
Herbicidal ionic liquids (HILs) are organic salts with herbicidal properties. Their anions are usually derived from traditional herbicides, and they are paired with cations of a synthetic or natural origin. Because of their hydrophobic nature and lower volatility, HILs are considered an environmentally friendlier alternative to traditional herbicides, which often persist in the environment, contaminate groundwater and are toxic even to non-targeted organisms. Nevertheless, the scientific research on HILs is mainly focused on their effects on plants. In this thesis, the hormonal activity of selected HILs was tested using human cell lines. In addition, the ecotoxic effect of HILs on soil microorganisms was assessed using the analysis of phospholipid fatty acids (PLFA). To study the ecotoxic effect, two different types of soil were incubated with HILs in a 28-day experiment. The soils were characterized by a different management approach - the soils were treated or untreated with pesticides in the past. The effect of the content of soil organic matter and clay minerals on how HILs interact with soil microorganisms was evaluated. The residual concentrations of HILs were quantified during the soil experiment to assess the effect of the management approach applied in the past on the degradation rate of...
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Kinetics of selected herbicides and their biodegradation in soil and water environments
Šabršulová, Anna ; Matoušková, Milada (advisor) ; Stibal, Marek (referee)
The three most commonly used herbicides in the Czech Republic (chloracetanilides, triazines and glyphosate) are also the herbicidal compounds found in the highest concentration in surface water. After agricultural application, they interact with soil and water due to their chemical properties and environmental factors affecting them. Adsorption coefficient, solubility in water environment, precipitation and drift have high impacts on the kinetics of these herbicides and degradates emerging from them. While moving through soil, parent compounds of mentioned herbicides are actively biodegraded by microorganisms, the most effective decomposers in nature. Biodegradation in soil and water environments is accelerated or slowed by temperature, moisture, quantity of microbial communities and many other environmental factors. Even if the microbial degradation is effective in a water or soil environment, there are many other new, arising compounds whose persistence in the environment is significantly higher than that of the parent compound. Degradates can end up in surface water by run off or wash out from agricultural fields and can remain there for decades depending on their chemical properties and natural conditions. Key words: surface water, herbicides, herbicides degradation products, rainfall-runoff...
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Study on stability of triazine based herbicides in water
Petrlíková, Kateřina ; Tesařová, Eva (advisor) ; Janečková, Lucie (referee)
The first aim of this thesis was to find a suitable analytical method for monitoring of stability of four s-triazine herbicides in water samples. Two columns - stationary phases C18, namely products of Waters and Astec were tested in HPLC system. The composition of ACN/H2O mobile phase was changed in the range from 90/10 to 60/40 (v/v). Baseline separation of prometone, propazine and prometryne was achieved on the Astec C18 column with mobile phase ACN/H2O 70/30 (v/v). This separation system was used for the study of stability. The stability of s-triazines was monitored in the period of six weeks. The samples of atrazine, prometone, propazine and prometryne water from water tap. All samples were detected at the wavelength of 221nm. No significant changes were found in the contents of s-triazines in the samples were measured in samples of water - water from Vltava, acidified water from Vltava, water from water tap and acidified water from water tap. All samples were detected at the wavelength of 221nm. No significant changes were found in the contents of s-triazines in the samples.
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Oxidative damage to cellular components after oxidative stress induction by specific herbicides
Kramná, Barbara ; Wilhelmová, Naďa (advisor) ; Ryšlavá, Helena (referee)
Oxidative stress is caused by overproduction and overaccumulation of ROS (reactive oxygen species). This state is responsible for cellular damage during unfavorable environmental conditions such as drought, low temperatures, salinity. In order to directly study oxidative stress at tobacco plants (Nicotiana tabacum cv. Xanthi) I used specific herbicides, MV (methyl viologen) and 3-AT (3- aminotriazole). There were several markers used for monitoring oxidative damage to cellular components: DNA damage detected by a comet assay, lipid peroxidation, carbonylated proteins and modification of activities of antioxidant enzymes CAT (catalase) and APX (ascorbate peroxidase). Fluorescent microscopy documented changes in a redox state of tobacco cells and a specific signal for peroxisomes was observed after treatment with higher concentrations of MV and 3-AT. Application of both herbicides caused significant DNA damage, while they worked in a different concentrations, MV in µM and 3-AT in mM. Another convincing oxidative stress marker for MV was protein carbonylation. The inhibition of antioxidant enzymes CAT and APX was less significant when compared to the effects of 3-AT. Decreasing membrane stability proved to be an universal oxidative stress marker for both herbicides. On the other hand, lipid...
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Influence of advanced oxidative processess on ecotoxicity of pesticides
Goma, Bernadette ; Procházková, Petra (referee) ; Zlámalová Gargošová, Helena (advisor)
The topic of this bachelor thesis is a study of the influence of advanced oxidation processes on the ecotoxicity of pesticides Metazachlor and Chloridazon. Both herbicides are commonly used to protect crops such as oilseed rape, turnips, chard or fodder beet against whole range of undesirable monocotyledonous and dicotyledonous plants. Application is most often on large areas and therefore pose a high risk to the quality of the environment. The possible influence on the representatives of producers and consumers of the aquatic ecosystem was monitored in the work. Solutions of pesticides, which were subjected to selected methods of treatment using advanced oxidation processes, were tested on aquatic organisms, specifically on crustaceans Daphnia magna and aquatic plant Lemna minor. From the results of individual tests, the ecotoxicological values of EC50 and IC50 were calculated and their ecotoxicity and thus the efficiency of oxidation processes in the removal of pollutants from wastewater were compared.
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Pesticide glyphosate and possibilities of its determination
Stará, Kristýna ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
This bechelor thesis deals with determination of glyphosate employing capillary isotachophoresis technique. The literature review is devoted to pesticide, their distribution and use, properties and methods for the glyphosate determination, capillary zone isotachophoresis and its use. Experimental part focuses on the application of capillary isotachophoresis for determination of glyphosate, for determination of glyphosate in commercial preparations and testing of glyphosate sorption in soil.
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Stanovení vybraných iontových herbicidů v povrchových vodách
Ondračka, Tomáš
The thesis deals with the determination of selected ion herbicides in surface waters and in the first part describes the herbicides. Given the broad spectrum herbicide further work deals mainly with glyphosate. The next section describes the electromigration methods and the methods by which the herbicides were determined. Finally, it describes how the development of an electrolyte system along with the use of graphical possibilities of computer technology. In conclusion are presented and commented on the results of measurements of glyphosate in surface waters, compared with foreign literature and assessing the suitability of methods for the analysis of contaminants in the environment.
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