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Development of soil nematode communities during primary and secondary succession
Benetková, Petra ; Frouz, Jan (advisor) ; Hendrychová, Markéta (referee) ; Renčo, Marek (referee)
Biodiversity loss is one of the biggest threats of our era. Habitats with all the unique species linked with them disappear due to the landscape changes and various mankind activities, namely obtaining of resources. Open-cast mining and intensive agriculture are an example of human activities that vastly degrades soil and diversity of its fauna. Therefore, ecosystem restoration is a way how to mitigate those losses and conserve or even bring back unique habitats. Despite the fact that most of restoration projects aim at plant communities, interest of soil fauna communities restoration increased amongst scientists lately. Nematodes serve as a very useful tool for a soil food web quality assessment. Their characteristics, such as various body length or different feeding habits makes them fit into almost all important ecological niches within the soil fauna group. This together with the fact that they are amongst first to colonize new habitats allows us to track changes in soil food web during primary or secondary succession. Moreover, using similar methodology and specific nematode indices developed over years enable comparison between different habitats and stages of succession. Restoration of soils and soil processes represent serious challenge in many restoration projects. Various restoration...
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Natural enemies of the European spruce bark beetle \kur{Ips typographus}
BÁRTA, Jiří
Bark beetles (Scolitynae) are among the most important pests of forest stands, where they cause extensive damage, especially in spruce monocultures. Their negative effect is to attack the host tree, which is its source of food and at the same time provides them with space for reproduction. The bark beetle is able to have several generations per year under suitable temperature conditions. One of the most widespread is consi-dered to be the European spruce bark beetle Ips typographus. This species is able to search for weakened and abiotically damaged trees. Integrated Pest Management of forests includes several effective methods against bark beetles. The most used met-hods include the installation of feromone traps, traps trees and poisoned tripods. The European spruce bark beetle is in their population regulated by many natural enemies. From parasitoids such as Coeloides bostrichorum and Rhopalicus tutela and predators Thanasimus formicarius and Medetera spp. to pathogenic microorganisms such as entomopathogenic viruses, bacteria, protozoa, microsporidia and especially entomo-pathogenic fungi belonging to the order Hypocreales. The most important species is the fungus Beauveria bassiana, which has the greatest potential in the biological pro-tection of spruce stands.
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Use of macroorganisms and microorganisms in biological control of aphids
BOŠKA, David
Aphids are one of the most important species of pests, occurring on all continents except Antarctica. Aphids are harmful mainly by sucking, honeydew production and transmitting hundreds of viral diseases. The most important greenhouse aphids occurring in the Czech Republic are the green peach aphid (Myzus persicae) and the cotton aphid (Aphis gossypii). Their danger lies in the rapid development cycle, when there is a rapid increase in populations. Despite the great damage they cause, aphids are very defenceless and small insect with a large number of naturally occurring enemies. The most important natural enemies are predators, parasitoids and entomopathogenic fungi. In the biological control of plants against aphids, the predator ladybeetles (Coccinellidae), lacewings (Chrysopidae) and the aphidophagous gall midge (Aphidoletes aphidimyza) are mainly used. In the nature, aphids are also regulated by hoverflies (Syrphidae). The most important aphid parasitoids are mainly the parasitic wasps Aphidius colemani, Aphidius ervi and Aphelinus abdominalis. From the microorganisms, the polyphagous entomopathogenic fungi are used, they cause primary infections in several species of pests. From the microorganisms, entomopathogenic fungi are mainly entomopathogenic fungi that can attack polyphagous more species of harmful organisms. The bioproducts based on entomopathogenic fungi Lecanicillium lecanii, Beauveria bassiana and Isaria fumosorosea are available on the foreign market. They were developed for biological control against aphids and other pests.
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Jsou parmy obecné v době výtěru "jedovaté" pro ostatní vodní organismy?
ŠVEJDA, Pavel
This bachelor thesis deals with fish toxicity with the emphasis on the barbel (Barbus barbus Linnaeus, 1758). Its tissues and especially roe cause poisoning to human known as a "barbel cholera". Possible lethal effects of barbel the killer shrimp Dikerogammarus villosus (Sowinsky, 1894), the marbled crayfish Procambarus virginalis Lyko, 2017 and the round goby Neogobius melanostomus (Pallas, 1814) were examined in this thesis. Different types of tissues and early life stages of barbel were used due to the indistinct distribution of possible toxin in fish body. In addition, using a behavior test, where marbled crayfish were used as an experimental organism, we monitored possibilities of toxin detection by consumer. Our results suggest that there is no evidence of barbel lethal toxicity on chosen consumers. We also did not find evidence that crayfish are able to recognize flesh of ready and unready to reproduce barbel. To sum up, we did not find evidence that toxin which is present in barbel body affect given consumers. It can be given either their co-evolution (arms race) or their ancestors had never been susceptible on this toxin. Thus, there can only be a spontaneous effect of mentioned toxin on mammals or humans.
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Spektrum škůdců a jejich antagonistů v okrasné a užitkové zahradě
Egriová, Sabina
In the growing season in 2016 there was in Petřvald u Karviné observed the presence of harmful and beneficial insects in ornamental and productive garden in a regular two-week intervals. There were defined three study areas in the garden, according to cultivated plants: ornamental plants, vegetables and orchard. Insects were monitored using colored bowls and pitfall traps. The best way of trapping insects are epigeic ground traps. Colorful bowls are most advantageous to monitor the occurrence of flying insects. There were observed abundance and representation of the trophic groups of insects. Caught total 2,917 individuals from 10 insect orders and 52 families. From the trophic point of view there were 720 phytophages, 1746 predators and parasitoids and 290 saprophage.
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Distribuce zajíce polního na Znojemsku a faktory, které ovlivňují jeho početnost
Žák, Zdeněk
This work is focused on breeding and hunting hare in two hunting grounds in the Znojmo region. To evaluate the distribution, monitoring options and the most important factors influencing the abundance hare and based on the results obtained, shall propose measures for population stability in the agricultural landscape. An overview of the number of hunted hares from 1924 to 2014 and in parallel the development of its main predator foxes from 1971 to 2014. Both hunting ground, I evaluated in terms of natural conditions and said the composition of forest trees and the standard of game. Furthermore, I have monitored the occurrence of hare, with a focus on disease leptospirosis, brucellosis and tularemia by hunted hares during 2014 in both hunting grounds. This work is also focused on the important factors limited the existence of hare in today's conditions, particularly the impact of human activities in agriculture, tourism, traffic and hunting. Based on the results, it showed that the largest share of the loss hare is today agricultural activity that consistently generates unsuitable conditions for hare especially large plots of grain cultivation and intensive chemical protection. This is also associated with a number of diseases and high mortality rates throughout the year.
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Škůdci hrachu při ekologickém a konvenčním pěstování
Matějková, Lucie
Occurrence of pests has been investigated in the district Vyškov on organically and conventionally grown pea in 2013. Monitoring of insects was carried from May to July using pheromone traps, sticky boards and check of plants. 13 590 individuals were determined on the organic, 6608 on the conventional plot. Acyrthosiphon pisum was the most numerous pest (10 811, 4335 individuals). Parasitism reached 67.5% on the organic plot. Other pests findings on organic and conventional plots were Aphis fabae (70, 88), Kakothrips robustus (1403, 316), Odontothrips confusus (251, 0), Autographa gamma (12, 12), Cecidomyidae (97, 191), Anthomyidae (0, 327). Other phytophagous species (350, 967), predators (159, 66), parasitoids (21, 7), decomposers (1, 17), pollinators (4, 2) and Cyclorrhapha of unknown significance (441, 280) were registered to organic and conventional plots.
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Predátoři jako součást systému biologické ochrany
Gaja, Martin
In the thesis I dealt with the processing of literary sources dealing with the feeding ecology of selected species of predators occurring in the Czech Republic and the importance of predators in biological protection. I received a detailed overview of the different types of food composition and on that basis decide on the usefulness or harmfulness of each. The result of this work is a comprehensive view of the importance of predators in the modern landscape, by people more or less affected.
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