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Dissemination of Cordyceps fumosorosea by entomopathogenic Nematodes
HOPFGARTNER, Miriam
C. fumosorosea is an entomopathogenic fungus that has been used as a biocontrol agent against various insect hosts for some time. Its efficacy as an entomopathogen can be increased by joined application of the fungus with entomopathogenic nematodes. The aims of this thesis are to investigate the impact of the foraging strategy of different nematode species on the spore dispersal of C. fumosorosea and the significance the nematode's 2nd stage cuticle holds for spore dissemination. Additionally, novel approaches for the enhancement of spore transmission in soil environments via adhesives are explored.
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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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Využití biologických prostředků na ochranu brambor vůči mandelince bramborové
KURÁŽ, Jakub
The aim of the work was to verify possibilities of biological control against Colorado potato beetle by using cultivated indigenous entomopathogenic fungi and entomopathogenic nematodes from potato fields in Czech Republic before chemical treatment or ecological agriculture and verify their efficacy against Colorado potato beetle. All results are included in attached charts or tables.
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Evaluation of development of various strains of Beauveria bassiana in different environmental conditions
ŠEBEK, Jaroslav
The entomopathogenic fungus Beauveria bassiana is a polyphagous species of fungus that attacks more than 700 species of hosts. This species of fungus is one of the most researched and most common representatives of entomopathogenic fungi. Many of bioproducts based on conidia or blastospores of B. bassiana are registered around the world. These bioproducts are used in biological control against various pests of field crops, fast-growing vegetables and ornamental flowers and in forest stands against certain pest species. The bachelor thesis focuses on the basic "in vitro" parameters of selected strains of entomopathogenic fungus B. bassiana from different geographical areas. The work focuses on the effect of temperature on the germination of strains of the entomopathogenic fungus B. bassiana. Furthermore, the growth and development of B. bassiana strains (radial growth) were compared. And the last part is focused on the comparison of spore production of strains of entomopathogenic fungus B. bassiana on standard nutrient medium and natural substrate.
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Possibilities of use of selected entomopathogenic fungi in biological control of agricultural pest species
KONOPICKÁ, Jana
Ph.D. thesis is focused on the entomopathogenic fungi that can be used in biological control. Ph.D. thesis consists of two main parts: 1) a detailed background research, and 2) five subchapters of the experimental part and results, which contain original publications describing results of my own studies. The first study focused on the isolation and identification of new strains of entomopathogenic fungi from soil samples collected in garlic and onion fields in the Czech Republic and Israel. Furthermore, the efficacy of selected fungal strains against the bulb mite Rhizoglyphus robini was tested. A total of 5 genera of entomopathogenic fungi (Metarhizium sp., Beauveria sp., Isaria sp., Lecanicilium sp. and Purpureocillium sp.) were identified among the soil isolates from both countries. The most frequent was the genus Metarhizium sp. especially in sampling sites of the Czech Republic. The highest efficacy against Rhizoglyphus robini mites was found in Metarhizium anisopliae strains isolated from soil samples collected in the Czech Republic and in Metarhizium indigoticum strain from Israel. Mortality after 4 days of the bioassay was almost 100%. The second study investigated the efficacy of the entomopathogenic fungus Isaria fumosorosea CCM 8367 against box tree moth (Cydalima perspectalis). Fungal infection was mostly observed in pupae. However, mortality did not exceed 60%, indicating a very low susceptibility of box tree moth to Isaria fumosorosea CCM 8367. In the third subchapter, various strains of entomopathogenic fungus Beauveria bassiana were tested against the Colorado potato beetle, a serious pest of potato. First, laboratory experiments were performed and the most virulent strain BBA 08 against this pest was selected and used subsequently in further experiments. The strain efficacy against L. decemlineata adults was evaluated in pot experiments and under field conditions. The fungus was applied alone and in combination with entomopathogenic nematodes. In all experiments, the fungus reduced the number of Colorado potato beetle adults by about 30% compared to the control. The fourth study described enrichment of soil substrate with entomopathogenic fungus Isaria fumosorosea CCM 8367 for increasing its suppressivity. The results showed that the fungus successfully colonized the soil substrate and remained in it for more than 6 months at 20 °C, although the average concentration decreased slightly from 5.89×104 to 2.76×104 spores per milliliter of substrate during the experiment. The last study described dissemination of Isaria fumosorosea CCM 8367 spores by nematodes of Steinernema feltiae and Heterorhabditis bacteriophora. The results of our study revealed for the first time that the spread of conidia and blastospores of Isaria fumosorosea in soil environment is significantly enhanced by the presence of entomopathogenic nematodes.
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Monitoring of occurrence and characterization of entomopathogenic fungi naturally associated with population of spruce bark beetle \kur{Ips typographus} L. (Coleoptera, Scolytidae).
PEJSAROVÁ, Hana
The use of entomopathogenic organisms is one of the possibilities of biological plant protection, which now prefers the protection of the chemical. In the field of scientific research with an interest in these organisms in recent years has increased significantly, particularly on the grounds that their use can avoid increasing the doses of chemicals that have harmful organisms after a period of vypěstují resistance. In any ecosystem are harmful agents and their natural enemies. By the monitoring Šumava NP and PLA we wanted to demonstrate the occurrence of entomopathogenic fungi, the natural enemies of insects. Specific harmful factor for us was spruce bark beetle. Using the location of occurrence of entomopathogenic fungi were obtained strains of several species (Beauveria spp., Isaria spp., Metarhizium spp. Lecanicillium spp.), Which attempts were made, determining the entomopathogenic potential. Rating strains was carried out by setting radial growth and yield of spores of these strains of entomopathogenic fungi. Strains were transferred to the testing carried out forms alginate pellets and stored in mycology collections in the Department of crop production for the purpose of further examination. The monitoring and follow-up experiments we gained valuable information about the current incidence of fungi in the environment and also data on the assumptions for the use of integrated plant protection. For further research have been used identified fungi Beauveria bassiana strains, which, according to the findings apply to most pathogenic sponge against lýkožroutu smrkovému and its most productive strains (NP 0030, NP 0052) are currently recommended for use in the biological fight against spruce bark beetle. The remaining species found entomopathogenic fungi are the subject of further examination at the Department of Plant Production University of South Bohemia.
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Use of entomopathogenic fungi in biological control against sweetpotato whitefly Bemisia tabaci
ŘEHOŘOVÁ, Markéta
The thesis is analyzing effects of selected species and strains of entomopathogenic fungi on the synchronized population of Bemisia tabaci under optimal and sub-optimal conditions. The following species of fungi were used during the experiments: Aschersonia aleyrodis, Lecanicillium lecanii (former Verticillium lecanii), Isaria fumosorosea (former Paecilomyces fumosoroseus) a Beauveria bassiana. There was a experiment of mortality of all these fungi in the frequency of 7, 14, and 21 days, while all these experiments were made under the same conditions (concerning temperature and humidity) in order to keep all the results comparable. In the case of Isaria fumosorosea, the experiment was taken also under sub-optimal conditions in order to compare effectiveness of this significant fungi, both under the optimal conditions (relative air humidity 95-100 %, temperature 25{$\pm$}1°C), and sub-optimal conditons (relative air humidity bellow 75 %, temperature 25{$\pm$}1°C). Greater attention was also given to A. aleyrodis which represents one of the most important fungi on the field of whitefly combat.
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Use of macroorganisms and microorganisms in biological control of whiteflies
ŽÁKOVÁ, Erika
Whitefly is one of the most important greenhouse pests that can cause significant damage to crops. Whitefly suck juice from plants and produce honeydew which is sugar source for saprotrophic fungi called sooty mold. Fungi cover the leaves and reduce the leaf assimilation area. The most serious harm of whiteflies is attributed to transfer of many plant viruses. The most serious whiteflies commonly found in the greenhouses are Trialeurodes vaporariorum and Bemisia tabaci. For the control of whitefly populations, the seasonal inoculum strategy of biological control is used, with the aim of immediately overlapping the pest with the right choice of natural enemies. Biological control contributes to the control of whiteflies in the greenhouse, specifically the use of natural enemies based on macro-organisms and microorganisms. The macroorganisms include parasitoids and predators. The most important commercially used whitefly parasitoids are Encarsia formosa, Eretmocerus eremicus and E. mundus. Predators used in biological control against whitely is the predatory bug Macrolophus caliginosus, the predatory ladybug Delphastus catalinae and the predatory mite Amlyseius swirskii. Parasitic wasps are narrowly specialized in both whitefly species, while predators are polyphagous species that can feed on more pest species. Bioproducts based on entomopathogenic fungi are also used against whiteflies in the abroad. The most important species are Aschersonia aleyrodis, Isaria fumosorosea, Beauveria bassiana and Lecanicillim muscarium. For the effective use of these bioagents, it is important to have knowledges not only about pest, but also about interaction among pest - natural enemy - host plant. So it is important to perform quality monitoring of whiteflies in the greenhouse to make the use of natural enemies profitable.
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Vzájemná kompatibilita entomopatogenní houby \kur{Isaria fumosorosea} s dalšími druhy entomopatogenních hub
OUŠKOVÁ, Šárka
This thesis is focused on evaluation of the compatibility of entomopathogenic fungus Isaria fumosorosea with different species of entomopathogenic fungi and mycoparasitic fungi at different temperatures. The strains of species Beauveria bassiana, Metarhizium anisopliae, Lecanicillium muscarium, Coniothyrium minitans and Clonostachys rosea f. catenulata were selected for experiments base on compatibility. The results showed that combination of I. fumosorosea with species L. muscarium is compatible. The species do not limit to each other in the environment at all temperatures (15, 23 and 25 °C). On the other side, fungus I. fumosorosea in combination with other species have affected their growth and spore production. The efficacy of entomopathogenic fungi against larvae Tenebrio molitor was evaluated. The most effective species against larvae were species I. fumosorosea, B. bassiana and M. anisopliae. On the contrary, the smallest effective was observed after infection larvae by L. muscarium. Mycoparasitic fungus C. rosea f. catenulata was not able to directly infect larvae of T. molitor. This species did not infect healthy larvae. However it is able to infect weakened individuals or is growing as saprotrophs on the cadavers.
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