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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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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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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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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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Acetyl - CoA carboxylase - evolution and inhibition
Chalupská, Dominika ; Čeřovská, Noemi (advisor) ; Plchová, Helena (referee) ; Vlček, Čestmír (referee)
Abstract
Acetyl-CoA
carboxylase
(ACC)
is
a
key
enzyme
of
fatty
acid
metabolism
with
multiple
isozymes
often
expressed
in
different
eukaryotic
cellular
compartments.
In
agriculture,
inhibitors
of
plastid
ACC
are
used
as
efficient
herbicides
against
grass
weed.
However,
grass
weed
populations
resistant
to
aryloxyphenoxypropionate
(APP)
and
cyclohexanedione
(CHD)
herbicides
represent
a
major
problem
for
sustainable
agriculture.
Using
PCR
and
sequencing
it
was
found
out
that
five
amino
acid
substitutions
in
plastid
ACC
were
correlated
with
herbicide
resistance
of
Avena
sterilis
ssp.
ludoviciana
Durieu
populations
from
the
northern
grain-growing
region
of
Australia:
Trp-1,999-Cys,
Trp-2,027- Cys,
Ile-2,041-Asn,
Asp-2,078-Gly
and
Gly-2,096-Ala.
We
showed,
using
a
yeast
gene- replacement
system,
that
these
single-site
mutations
also
confer
herbicide
resistance
to
wheat
plastid
ACCase:
Asp-2,078-Gly
confers
resistance
to
APPs
and
CHDs,
Trp-2,027-Cys
and
Ile-2,041-Asn
confer
resistance
to
APPs,
and
Trp-1,999-Cys
confers
resistance
only
to
fenoxaprop.
These
mutations
are
very
likely
to
confer
resistance
to
any
grass
weed
species
under
selection
imposed
by
the
extensive
agricultural
use
of
the
herbicides.
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