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Inhibition of the etiological agent of American foulbrood disease using selected essential oils
ZÁLABSKÁ, Adéla
Americal foulbrood disease, caused by etiological agent Paenibacillus larvae is serious disease which affects honey bee that is prohibited to treat with antibiotic in the Czech Republic. If the disease occurs in hive, it is a legal requirement to burn the hive. Essential oils have antimicrobial aktivity and their use can help fighting this dangerous disease. The aim of the bachelor thesis was to verify the bactericidal effect of selected essential oils on the causative agent of the americal foulbrood disease P. Larvae. Another stated aim was to determine the minimum inhibitory and bactericidal concentrations of the selected essential oils. A total of 11 essential oils were used and evaluated both alone and in combination with other essential oils. The evaluation was carried oud on microtiter plates using spectophotometer and on agar medium in petri dishes. The most effective essential oil was garlic oil (Allium sativum bulb oil), which had minimum and bactericidal concentration values of 32 ?l/mg. Other very effective plant essential oils include cinnamon essential oil (Cinnamomum zeylanicum bark oil). The least effective essential oils are carrot oil (Daucus carota sativa seed oil), thyme oils (Thymus serpyllum oil, Thymus vulgaris flower/leaf oil) or oregano oil (Origanum vulgare).
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Zimování včelstva
Babica, Ondřej
In the breeding of honeybees (Apis mellifera L.), the good health of the bee colony is an important prerequisite for successful overwintering. The condition of the colonies is affected by environmental influences, the influence of genetics or the health status of the bees. Well-developed pharyngeal glands allow bee feeders to provide developing larvae with quality royal jelly. The longevity of the winter generation of bees is influenced by a many of physiological factors, which distinguish them from summer short-lived bees. The main factors of longevity appear to be the level of proteins in the hemolymph, especially vitellogenin, the level of juvenile hormone or the pheromone ethyl oleate. The natural immune system or the effects of oxidative stress also play an important role in the overwintering of colonies. Recently, overwintering is threatened by viral infections transmitted by varroa mite.
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Obranné reakce hmyzu vůči intoxikaci: modelový druh včela medonosná
PROKŮPKOVÁ, Nela
This bachelor thesis aimed to characterize the effect of imidacloprid (neonicotinoid insecticide) on nutrient levels (carbohydrates, proteins, lipids) in haemolymph, on the activity of digestive enzymes (amylases, proteases, lipases) in the gut, and on adipokinetic hormone and biogenic amine levels in the central nervous system of the worker honeybees Apis mellifera. The insecticide was applied topically to the bee body at a dose of 0,04 micrograms per bee. The above-mentioned characteristics were measured 24 hours after insecticide application. The results showed that the effect of imidacloprid on the nutrient level in haemolymph was variable - the level of carbohydrates and proteins decreased, while the level of lipids increased. The activity of digestive enzymes in the gut increased (proteases, lipases) after the application of imidacloprid. On the other hand, the levels of adipokinetic hormone and biogenic amines in the central nervous system were reduced.
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Insect pollinators issues and alternative methods of control of fungal, bacterial, and parasitic diseases of bees
MRÁZ, Petr
This Ph.D. thesis is focused on the importance of insect pollinators and pointed out to their loss due to intensive agriculture. Great attention is paid to the honey bee as the main pollinator, especially to the issue of quality nutrition of bee colonies in connection with the support of detoxification of pesticides. Furthermore, the main effort is devoted to alternative possibilities of control of selected bee pathogens and research of their prevalence in the Czech Republic. The work is divided into two main parts: a detailed background research and an experimental part consisting of six subchapters with results from my own research studies. The first study deals with the effect of pollination on the qualitative and quantitative yield parameters of honeysuckle. Several pollination variants were tested and the best result in all monitored parameters was achieved by the pollination with natural pollinators. Variants of manual pollination and without pollination caused uneven maturation of fruits and lower yields. Furthermore, the diversity and abundance of pollinators in the vicinity of this crop were observed and the most suitable pollinators identified which appear to be bumblebees and the honey bee. The second study deals with the impact of agricultural intensity on the diversity and abundance of pollinators in the landscape. Localities with organic and conventional management regimes were compared. Significantly higher diversity and abundance of pollinators was recorded in the locality managed by organic farming. In addition, the contamination load of pesticide residues in bee's body was also monitored. Residues of several pesticides were detected at the site with conventional agriculture, while none of them were detected at the site with organic farming. The third study examines the effect of nutrition, specifically phenolic substances, on the ability of bees to detoxify the pesticide to which they have been exposed. In the experiment, the bees in the cages were fed with a mixture of selected polyphenols, commonly found in pollen, and the pesticide thiacloprid. Mortality and daily feed consumption were monitored for 14 days, and the expression level of detoxification genes was analyzed at specified intervals. Phenolic substances have been shown to have a positive effect on the lifespan of intoxicated bees, as well as higher feed consumption, which may indicate an increased need for these substances. In contrast, the increased expression of detoxification genes was not confirmed. Other studies focus on honey bee pathogens. One of them monitors the occurrence and prevalence of selected major bee pathogens in the Czech Republic and compares different types of habitats, such as urban areas, agriculturally intensively cultivated areas and protected natural areas. Surprisingly, the most often detected pathogen was Lotmaria passim. From the viral diseases, the highest rate of occurrence had DWV complex and ABPV. In general, more eukaryotic pathogens were found in cities and agricultural landscapes. On the contrary, more viral diseases were recorded in the protected natural area. The fifth subchapter consists of 4 publications and deals with the use of essential oils to control the Varroa destructor mite and the entomopathogenic fungus Ascosphaera apis. The first publication compares the growth and development of the fungus A. apis on different culture media and proposes a new medium with the addition of bee brood, on which the greatest sporulation was recorded. Another 2 publications deal with the fungicidal effect of selected essential oils in laboratory conditions. The best results were shown by essential oils of thyme, cedar wood, cloves and cinnamon. The fourth publication deals with the acaricidal effect of selected essential oils on the V. destructor mites and at the same time evaluate the toxicity of these oils to adult bees. Based on these results, essential oils with the highest LD50 to bees / LD50 to mites ratio (sele
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Effect of pollination on seedset and yield of buckwheat (\kur{Fagopyrum esculentum}).
NOLČ, Radek
Common buckwheat is a attracting plant for many pollinators, therefore it be helping to restore biodiversity in the landscape. The most important of pollinators of buc kwheat are honeybee and hoverflies. The aim of this thesis was to find out effect of pollination of buckwheat sown with honeybees and the others pollinators on the seed set and yield of archenes in different varieties of buckwheat. A small-plot field experiment was established with three varieties of common buckwheat in the Pilsen Region, in the place of Zábělá. Before flowering began, half of the plots were covered with insect screens. The buckwheat stand was evaluated from the point of: plants height, number of branches, number of flowers and inflorescences on a plant, nectar volume in Thrum flowers, flowering time, number of archenes on a plant, the weight of thousand of archenes and the yield of archenes. Monitoring of pollinators was performed at the time of buckwheat flowering at 9, 10, 11, 12 and 14 hours, during 10 minutes, using photos. Nectar collection took place on five consecu tive days, from 16. 7. until 20. 7., at 9, 10 and 11 hours. Total of 31 insect species were recorded on buckwheat flowers. The most common effective pollinators of buckwheat were honeybees, (39,7 %) and hoverflies (37,5 %). The significant difference in nectar production was found among the tested buckwheat varieties. The yield of achenes on covered plants was 87 % lower than on freely accessible plants.
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Honey bee - didactic model for environmental education in preschool education
KOŠNEROVÁ, Eva
Presented bachelor thesis is focused on science education of preschool children with the aim to apply educational activities. The introductory part of the thesis defines the basis of. The importance of the stay of preschool children in the outdoor environment is emphasized. The main task of this thesis is to present ideas for educational activities for preschool education, which are focused on the honey bee. Each performed activity contains detailed description of the activity, its own implementation and reflection.
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Morphological and molecular characterization of yeasts from the genus \kur{Zygosaccharomyces} associated with honey bees
JAVŮRKOVÁ, Petra
Beekeeping is one of the oldest fields of human activity. A key role in this field is played by the honey bee (Apis mellifera), which is also an important pollinator of agricultural crops and wild plants. Although bees have evolved defense mechanisms during their long evolution against a variety of external influences, bee´s existence is currently threatened by several factors. An interesting way for increasing the immunity of the bee colony seems to be the honey bee microbiome. Honey bee microbiome is the main focus of this thesis, with a practical part focused on yeasts of the genus Zygosaccharomyces. Twenty samples/strains of the yeasts were isolated from the intestines of bee larvae, pollen baskets, and pollen on selected culture media. Based on sequencing of the D1/D2 region of the large ribosomal DNA subunit, three species of the genus Zygosaccharomyces were identified in these twenty samples: Z. rouxii, Z. favi and Z. mellis. Four pairs of primers were also designed within the ITS region and can be an alternative or complement to the molecular characterization of isolated yeast strains based on another marker region of DNA. All primers were evaluated as specific for Z. rouxii species. Using one pair of primers, the part of ITS region was also amplified in the species Z. mellis. According to this, these primers could also be used to identify this species as well. The last part of this work is the determination of ergosterol production in yeast biomass by HPLC. Ergosterol is produced by the Zygosaccharomyces yeasts and it plays an important role in the development of the bee brood. It was found in this thesis, that ergosterol levels in yeasts are not uniform and also do not correlate with biomass production. The highest production of ergosterol was found in the species Z. mellis, which is a sample obtained from pollen. The outputs of this work provide a new perspective on the colonization of the intestinal microbiota of bees and also offer potential significance for the future, especially in the application of yeast as a source of ergosterol for developing larvae.
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Vliv přírodních toxinů na včelu medonosnou
KAINZOVÁ, Klára
The aim of this bachelor thesis was to describe the effect of honeybee venom on the activity of digestive enzymes (amylases, proteases, lipases), AKHs production in CNS, and level of nutrients (lipids, proteins, glycides) and vitellogenin in haemolymph of the honeybee Apis mellifera workers. Crude venom was applied into the honeybee body 24 hours before determination of the above mentioned characteristics. Results showed that the bee venom reduced the AKH level in CNS, increased activity of digestive enzymes in gut, and increased level of vitellogenin in haemolymph. Effect of the venom on nutrient level in haemolymph was variable - level of lipids and carbohydrates was enhanced, while level of proteins reduced.
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Monitoring of Paenibacillus larvae, Melissococcus plutonius and Ascosphaera apis pathogens in honeybee colonies in the Czech Republic
JOSKOVÁ, Markéta
The aim of this thesis was to summarize the theoretical informations about biology of honeybees and bacteries Paenibacillus larvae and Melissococcus plutonius and parasitic fungi Ascosphaera apis. This organisms attack bee larvae and cause bee diseases. The major part of this thesis was focused on the evaluation of the occurrence of these pathogens in various places in Czech Republic by isolating bee DNA from more than 200 bee samples from 50 locations within whole Czech Republic. Detection pathogens was performed using PCR method. There were 3 samples positive for Paenibacillus larvae and 4 positive for Melissococcus plutonius. The fungus Ascospheara apis did not occur in any of the samples.
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Monitoring of SBV, SBPV and ABPV viruses in colonies in the Czech Republic
ZLÁMALOVÁ, Aneta
In this diploma thesis I deal with one of the current topics, namely the worldwide decline of bee colonies. The honey bee faces a number of factors that affect its health, condition and viability. These factors include, but are not limited to, bee viruses, many of which cause bag fetal virus or bee paralysis, whether acute or slow. Due to viral diseases, infected bees cannot play their role in the hive and the growing number of affected bees can negatively affect the entire bee colony.
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