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Litter decomposition and its role in biogeochemical cycles
Vicena, Jakub ; Frouz, Jan (advisor) ; Picek, Tomáš (referee) ; Krištůfek, Václav (referee)
Decomposition of litter is a key process in the soil nutrient cycle. It is a very complex process that is influenced by a number of factors. This dissertation studies these key factors influencing the rate of organic matter mineralization using modern analytical methods. The results of the dissertation are presented in four publications in international journals with IF and one manuscript ready for publication. The first publication shows a strong positive correlation between microbial diversity and organic matter decomposition per gram of carbon. In contrast, microbial respiration per gram soil was negatively correlated with bacterial diversity and positively correlated with fungal biomass. Thus, the relationship between microbial diversity and decomposition rate is context dependent. The second study (in manuscript form) shows that microbial respiration correlates with C/N of fallout only at the beginning of the experiment, but not at the end. However, respiration during litter decomposition at the beginning and end of the experiment is strongly negatively correlated with the C/N ratio of green leaves. This suggests that the stoichiometric C/N ratio may influence decomposition indirectly through correlation with other unknown parameters such as leaf morphology. The third study examined the...
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Differences in physiology between r and K bacterial strategists.
Moserová, Andrea ; Konopásek, Ivo (advisor) ; Krištůfek, Václav (referee)
Differences in physiology between r and K-bacterial strategists. The definition of bacterial r/K-strategists is currently based on the time interval they need to form a colony on agar plate. Also, their growth rate which is often used to identify r/K-position within a pair of bacterial strains. To date it was evidenced that also other physiological characteristics relate to bacterial r/K-status, for example their different ability to 1) adapt for changing conditions 2) utilize complex or very diluted substrates, 3) use secondary metabolites to cope with other strains and possibly also others. The intersection of macro- and microbiological r/K-conceptions lies in time distribution of r/K-strategists during succession. The aim of this study was to verify the basic r/K-characteristics on nine chosen strains and to correlate them with their physiological differences that are implicitly regarded as characteristic for r/K-groups. The study deals with growth rates measurements on both liquid and solid media, identification of fatty acid composition and membrane fluidity of strains cultivated at near-optimum and cold temperature in order to track the differences in cold adaptation. The study also deals with the description of possible new K-strategist characteristic: the lack of correlation between the colony...
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Differences in physiology between r and K bacterial strategists.
Moserová, Andrea ; Konopásek, Ivo (advisor) ; Krištůfek, Václav (referee)
Differences in physiology between r and K-bacterial strategists. The definition of bacterial r/K-strategists is currently based on the time interval they need to form a colony on agar plate. Also, their growth rate which is often used to identify r/K-position within a pair of bacterial strains. To date it was evidenced that also other physiological characteristics relate to bacterial r/K-status, for example their different ability to 1) adapt for changing conditions 2) utilize complex or very diluted substrates, 3) use secondary metabolites to cope with other strains and possibly also others. The intersection of macro- and microbiological r/K-conceptions lies in time distribution of r/K-strategists during succession. The aim of this study was to verify the basic r/K-characteristics on nine chosen strains and to correlate them with their physiological differences that are implicitly regarded as characteristic for r/K-groups. The study deals with growth rates measurements on both liquid and solid media, identification of fatty acid composition and membrane fluidity of strains cultivated at near-optimum and cold temperature in order to track the differences in cold adaptation. The study also deals with the description of possible new K-strategist characteristic: the lack of correlation between the colony...
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Common scab important problem at growing of potato
Diviš, J. ; Krištůfek, Václav
Potato varieties with high susceptibility (Agria) and low susceptibility (Kariera) to common scab were grown on both the sites with a low occurrence and with a strong occurrence of common scab. The degree of common scab was evaluated by using the scale of Wenzel and Demel (1967). The obtained results confirmed tne significant position of the variety as the indirect measure of common scab protection. It is possible to use both varieties Agria and Kariera for indication of common scab occurrence at field conditions.
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Culture Collection of Soil Actinomycetes in the Institute of Soil Biology BC ASCR, v.v.i. České Budějovice
Krištůfek, Václav ; Chroňáková, Alica ; Elhottová, Dana ; Petrásek, Jiří ; Němec, Jan
The Culture Collection of Actinomycetes in České Budějovice (CCACB) was established in 2006 that serves as a depository for cultures of soil actinomycetes. The cultures can be used for research, industrial applications, education and general scientific interest. Cultures are preserved mainly in glycerol or freeze-dried conserves. CCACB will offer strains of actinomycetes, namely streptomycetes (more than 900 cultures at the present moment), in catalogue of cultures www.upb.cas.cz, www.actinomycetes.cz.
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Detection of microorganisms in the soil using CARD-FISH (Catalyzed Reporter Deposition - Fluorescence in situ hybridization)
Krištůfek, Václav ; Kasalický, Vojtěch ; Chroňáková, Alica ; Elhottová, Dana ; Němec, Jan
CARD-FISH protocol (Catalyzed Reporter Deposition - Fluorescence in situ Hybridization) for detection of soil microbial community composition was successfully established in the Institute of Soil Biology. CARD-FISH is the relatively new molecular biology tool permitting to quantify distinct groups of microorganisms by hybridization of specific oligonucleotide probes. Compared to classic FISH-protocol the probe-attached enzyme amplifies the fluorescent signal and enables to detect nearly all microorganisms in soil or in organic compounds. As the first, we used this method to determine the bacterial community composition of a dated layer of guano-heap from Domica Cave (Slovak Carst National Park, Slovakia). We quantified the percentuel composition of Archaea, Eubacteria (.i.Planktomycetales, Verrucomicrobiales./i. included) and major bacterial groups (Actinobacteria, proteobacteria, .i.Cytophaga-Flavobacter./i.-Bacteroidetes, Sphingobacteria).
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The cultivation of bacteria originated in bat guano
Petrásek, Jiří ; Elhottová, Dana ; Krištůfek, Václav ; Kováč, L.
The bat guano represents an important source of organic matter in the oligotrophic caves. The high content of chitin from the remains of digested insect in bat diet causes the slow decomposition of the guano. The bat guano deposits can be auccumulated near the bat colonies during hundreds of years. The bat guano represents unique environment with specific conditions and appropriate composition of bacterial community. In this study, the bacterial communities of the guano from Domica and Ardovská Caves (NP Slovak Karst) were investigated using plate method with six different growing media. Total numbers of cultivable aerobic bacteria in guano were determined on the solid complex medium TSBA (Becton & Dickinson]. Total numbers of cultivable anaerobic bacteria were determined on the DifcoTM Anaerobic agar and blood agar (Schaedler agar with 5% sheep blood).
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Microarthropods and microbial participation in oak and beech litter decomposition
Farská, Jitka ; Jínová, Kristýna ; Jirout, Jiří ; Petrásek, Jiří ; Čápová, Lenka ; Rusek, Josef ; Krištůfek, Václav ; Elhottová, Dana ; Starý, Josef
The aim of our work was to describe the impact of a simulated vegetation zone shift to higher altitudes (i) on the quantity and quality of microarthropods and microbial communities, and (ii) on the decomposition rate of allochthonous leaf litter. In November 2002, 480 litterbags filled with oak or beech leaf litter were placed into spruce and beech forests (950 m a. s. l.) on Kleť Mt. (1083 m; Blanský les Protected Landscape Area, South Bohemia). Three different mesh sizes were used for certain soil biota exclusion: > 2 mm, 0.5 mm and 42 μm. Litterbags were sampled after 2, 4, 6, 12, 24 and 36 months of exposure in the field. Litter pH and moisture were determined in the laboratory immediately after retrieval. Soil microarthropods (Oribatida, Gamasida and Collembola) were extracted using Tullgren funnels. Soil bacteria and micromycetes were isolated using the dilution plate method and specific growth media.
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