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Vyhodnocení aktuálního zaplevelení polních plodin ve vybrané lokalitě kukuřičné výrobní oblasti
Řičica, Tomáš
The aim of this bachelor thesis is to evaluate the actual weeds of field crops in the monitored enterprise plant situated in the corn production area. Monitoring was carried out in 2018 in rape, wheat and maize. The work also evaluates the comparison of weed infestation in unlimited and pesticidal bands. In the monitored crops, species were mostly found: Aspera spica-venti, Capsella bursa-pastoris, Geranium pussilum, Chenopodium album, Setaria viridis, Stellaria media, Thlaspi arvense, Veronica persica.
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Plevele v kukuřici a možnosti jejich regulace
Vaida, Matěj
The bachelor thesis deals with weed problems and possibilities of their control in maize. In the experimental part, a small-plot field trial was evaluated, which compares the biological effectiveness of different herbicides on selected weed spectrum. The results show that weed control in maize is possible to use different active ingredients applied in different application terms - pre-emergence, early post-emergence and post-emergence. The yield of maize grain on all herbicide-treated variants was comparable to the mechanically deflated variant. On the untreated variant there was a statistically significant decrease in yield.
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Vyhodnocení zaplevelení polních plodin na vybraných pozemcích
Němec, Rostislav
The main objective of the thesis is to evaluate the weed infestation of selected field crops on the lands of the agricultural cooperative Klenovice na Hané. The monitoring was carried out from the end of summer 2016 until the beginning of autumn 2017. The selected crops were the most grown ones, barley (Hordeum vulgare), common wheat (Triticum aestivum), rapeseed (Brassica napus var. napus), maize (Zea mays) and sugar beet (Beta vulgaris subsp. vulgaris convar. vulgaris var. altissima). The investigation of weed infestation of field crops was carried out during fieldwork using numerical method and the delineation of 1 m2 with following processing using canonical correspondence analysis (CCA). Mostly were found these kinds of weeds Apera spica-venti, Atriplex patula, Brassica napus var. napus, Capsella bursa-pastoris, Cirsium arvense, Descurainia sophia, Elytrigia repens, Galium aparine, Chenopodium album and Tripleurospermum inodorum.
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Regulace plevelů v porostu mrkve obecné pěstované na semeno
Coufal, Václav
The aim of this bachelor thesis was the elaboration of a literature review on weed control in carrot (Daucus carota) for seed production and to conduct laboratory experiment focused on testing selectivity and efficacy of herbicides in carrot using the chlorophyll fluorescence imaging technique. The aim of this experiment was to evaluate the efficacy of selected herbicides on common lambsquarters (Chenopodium album) and their phytotoxicity on carrot plants under pre-emergence and post-emergence applications. In addition, preemergence applications were performed in two variants simulating contrast soil conditions. The first was an organic substrate and the other quartz sand. Altogether, 8 herbicide active ingredients were used, some of which are registered in carrots, and some were previously tested abroad, thus providing the potential for improving the system of chemical weed control in carrots. These were carfentrazone-ethyl, clomazone, diflufenican, linuron, mesotrione, metribuzin, pendimethalin and S-metolachlor. Under preemergence application in the organic substrate, the best results were achieved with linuron and pendimethalin, both exhibiting high efficacy against common lambsquarters and low phytotoxicity to carrot plants. Preemergence application of herbicides in quartz sand showed a clear increase of phytotoxicity of preemergence herbicides. Increased phytotoxicity was evident in almost all herbicides, but mostlyin linuron. On the other hand, a decrease in phytotoxicity was found in diflufenican. The lowest phytotoxicity rate was observed for pendimethalin. In early post-emergence applications, the efficacy of all selected herbicides ranged above 90%. The lowest level of phytotoxicity was observed for pendimethalin, linuron, clomazone and mesotrione. Chlorophyll fluorescence imaging represents a very good tool for early assessment of the physiological herbicide effect, however, the evaluation by chlorophyll fluorescence in herbicides affecting directly photosynthesis led to overestimation the effects in comparison with other herbicides.
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Vliv herbicidu s-metolachloru na raná vývojová stádia raka mramorovaného
MATERNA, Jan
S-metolachlor is a substance belonging to the group of herbicides, widely used in agriculture to protect crops. This substance with the chemical composition C15H22CINO2 and is used as the pre-emergent herbicides to control unwanted weeds. The aim of this work was to evaluate the influence of s-metolachlor on mortality, behavior, growth, ontogenetic development, oxidative stress level and activity of antioxidant enzymes of early developmental stages of marbled crayfish (Procambarus fallax f. virginalis). The effect of s-metolachlor was evaluated on the basis of embryo-larval toxicity test. Early developmental stages of crayfish were exposed to three concentrations of s-metolachlor, 1.1 micrograms/l, 11 micrograms/l and 110 micrograms/l for 45 days. All tested concentrations significant showed higher mortality, delay of ontogenetic development, lower growth and changes in behavior (total movement distance and movement speed). Moreover, significant decrease in catalase, glutathione-s-transferase, superoxide dismutase concentration, and reduced glutathione levels at the two higher test concentrations (11 micrograms/l and 110 micrograms/l) of s-metolachlor were observed. No significant changes in oxidative damage (TBARS levels) were observed in all the tested groups. Based on the results of this study, early developmental stages of marbled crayfish can be recommended as suitable organisms for toxicity test and their use for biomonitoring of the aquatic environment by herbicides.
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Metody a možnosti regulace plevelů v jarních obilninách
DVOŘÁK, Jan
The thesis focused on description and characteristics of spring wheat and barley and their life cycles. Thesis deals with the issue of very dangerous weed plants and deals with the possibilities of their regulation by using herbicidal preparations in the growth spring cereals. Weeds are problematic plants that negatively affect the quality of production and also the economy of cultivation. Part of the thesis is the evaluation of a small plot experiment, which was performed in the crop of the spring barley on the land of the company AGRO Dolní Bukovsko in the cadastral area of the village Sedlíkovice in the direction (of Veselí nad Lužnicí) and in the spring wheat on the land of the above mentioned company in the cadastral territory of the municipality of Radonice in year 2017. Results of weed frequency and economic evaluation of the experiment are presented in tables and graphs.
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Vliv triazinových pesticidů a jejich metabolitů na necílové vodní organizmy
KOUTNIK, Dalibor
Pesticides used in agro-ecosystems and forests enter aquatic environments such as streams, rivers, and lakes if applied in adjacent areas or if an accidental spill occurs. For the studies, we chose the early life stages of common carp (Cyprinus carpio L.) and marbled crayfish (Procambarus fallax f. virginalis). In selected organisms, we observed long-term effect of triazine herbicides (prometryne, terbuthylazine, metribuzine) and their metabolites (terbuthylazine-desethyl and tebuthylazine-2-hydroxy) in concentrations commonly occurring in Czech rivers. The first part is about monitoring the effects of triazines (prometryne, terbuthylazine) on the early development stages of carp and marble crayfish. Subchronic prometryne exposure of early-life stages of common carp at concentrations of 1 200 and 4 000 ?g/L affected their survival, growth rate, early ontogeny, and histology. Terbuthylazine in concentration 1 400 and 3 000 ?g/L caused significant decrease of mass, total length, delayed in development and cause of alternation of tubular system of caudal kidney of carp. Prometryne in concentration 144, 1 444 and 4 320 ?g/L caused decrease of weight, specific growth rates and caused histopathological changes in gill of crayfish. Moreover concentration 4 320 ?g/L of prometryne caused delay in ontogenetic development of crayfish. Second part of the work has included effects of low concentrations of metabolites (terbuthylazine-desethyl and tebuthylazine-2-hydroxy) on the early development stages of carp and marble crayfish. Chronic terbuthylazine-desethyl exposure in concentrations 180, 900, and 1 800 ?g/L affected growth, ontogenetic development, and the antioxidant system and caused pathological changes in the caudal kidney of early life stages of carp. Chronic terbuthylazine-2-hydroxy exposure in concentrations 2.9, 70, 1 400 and 3 500 ?g/L caused decreased of total superoxide dismutase activity of early life stages of carp. Moreover concentration 1 400 and 3 500 ?g/L of terbuthylazine-2-hydroxy caused delay in ontogenetic development and pathological changes in the caudal kidney of carp. Chronic terbuthylazine-2-hydroxy exposure in concentrations up 75 ?g/l affected growth, ontogenetic development, antioxidant system, caused oxidative stress and pathological changes in hepatopancreas of early life stages of marbled crayfish. The last part of our study examined the effect of metribuzine on signal crayfish (Pacifastacus leniusculus Dana). Crayfish were exposed to metribuzine concentrations of 0.52 ?g/L and 3.06 mg/L for 30 days and a 30-day depuration period. In the thiobarbituric acid reactive substances, superoxide dismutase, and catalase were observed differences in all examined tissues (gill, muscle, hepatopancreas) compared to the control group. Differences from control were observed in glutathione reductase activity in hepatopancreas after 10 days for both exposure concentrations and after 30 days at 3.06 mg/L. Histological examination revealed extensive focal autolytic disintegration of tubular epithelium in hepatopancreas of crayfish exposed to metribuzin. These studies provided important results for the evaluation of long-term impact and effect of (prometryne, terbuthylazine and metribuzine) and their metabolites (terbuthylazine-desethyl and tebuthylazine-2-hydroxy) on the water non-target organisms, even in real concentrations founded in surface waters.
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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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Certified method for evaluation of biological efficacy of controlled atmospheres and fumigation in silos using biotest kits: methodology for workers in DDD, agriculture and food industry
Aulický, Radek ; Stejskal, Václav ; Plachý, Jan
Evaluation of the efficacy of controlled atmosphere or insecticide fumigation treatment of stored commodities is very difficult when these materials are located in silo bins. The main difficulty is to take measurements and samples within the entire commodity (vertical-silo) profile. Until now, there are no standard procedures and tools that would allow the evaluation of efficacy of controlled atmospheres under such situations. These methodical deficiencies are some of the main reasons why t controlled atmosphere methods are not commonly used in practice, although they are – under many conditions - relatively cost-effective disinfection measures. This methodology is the first Czech set of procedures for the proper preparation, application and evaluation of bioassays that can be used for evaluation of the efficacy of controlled atmospheres and fumigation in silo bins cells. The methodology also shows some practical examples and experimental results on how to use bioassay. The certified methodology was prepared with the financial support of the NAZV agency and is the technological an scientific output of the project QJ1310057.
Fulltext:  PDF
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Hodnocení subchronického působení atrazinu na raka (Cherax destructor)
HLÁVKOVÁ, Markéta
The evaluation of the sub-chronic exposure to atrazine on crayfish The aim of this study is to evaluate the sub-chronic effect of atrazin on a behaviour, oxidative stress, antioxidant enzyme aktivities and biochemical profile of haemolymph in. These complex data should help to appraise the impact of this substance in the environment. The total test duration was 28 days and was divided into two periods. The first 14 days the crayfish were exposed to two concentrations of atrazine: 6.86 micrograms per liter (ATRenv = environmental concentration in the water in the Czech Republic) and 1.21 milligrams per liter (ATR10% = is coincident to 10% LC50). After the atrazine treatments the depuration 2 weeks phases in water without any chemicals followed. The results indicate that sub-chronic effect of atrazine influenced neither the behaviour of the crayfish nor the level of oxidative stress (measured by TBARS), whereas the changes of superoxiddismutase (SOD) were observed in all tissues (muscles, gills and hepatopancreas). The changes of enzyme activity were observed in catalase (CAT; hepatopancreas and the muscle tissue), glutathione S-transferase (hepatopancreas and the gills tissue), glutathione reductase (GR; the hepatopancreas tissue) and reduced glutathione (the muscle tissue). The influence of ATRenv on the biochemical profile of haemolymph at the following parameters was estimated only for lactate and alkaline, however phosphatase changes made by ATR10% were significant for glucose, ammonia, lactate and alkaline phosphatase measurements. The sub-chronical effect changed the activity of all antioxidant enzymes in hepatopancreas, muscles and the gills tissue of the observed crayfish. The presented results in this study are giving compact information of impact of atrazine on the crayfish and the whole water environment. The suggestion of using the crayfish for tests of toxicity looks like an ideal supplement for triazine herbicide estimations.
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