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Pollinator pollen carryover effectiveness and plants' ability to enhance it
Freudenfeld, Martin ; Janovský, Zdeněk (advisor) ; Mikát, Michael (referee)
Pollinators carry over pollen from one flower to another. They facilitate plant reproduction. Pollinator functional groups differ in their effectiveness of pollen carryover. Quantity of pollen grains on their body and deposition on stigma are very important. Pollinator carryover capacity depends on its functional traits. Body size, hairiness, visitation behaviour, foraging preferences, flower constancy and abundance of pollinators are significant. Plants can enhance effectiveness of their pollination by adaptations to specific pollinator functional groups. They improve positioning of pollen on pollinators by specific changes to floral morphology, quantity and size of pollen grains. They can also enhance the effectiveness through aggregation of pollen grains into groups or into pollinia or by optimisation of pollen release in time.
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Pollination in forest ecosystems
Veljačiková, Hana ; Janovský, Zdeněk (advisor) ; Hadrava, Jiří (referee)
Interactions between plants and their pollinators in temperate forest are different from open habitats. In forest, pollinators are less abundant and this results in frequent pollen limitation of forest understory herbs. Pollinators also need to be adapted for flying in complex stands and for living in unfavorable microclimatic conditions. Floral resources predominantly limit pollinator abundance because of their uneven distribution in space and time. In the present bachelor thesis, I summarize knowledge on pollinator conservation and phenology as well as food resources, microclimate, which together with sufficient nesting options seem to contribute the most to pollinator abundance. Type of forest management is also an important factor, which affects density and diversity of pollinators. Generally, thinning out of trees and removal of understory shrubs have positive effect on flower abundance and benefit pollinators. Factors that influence reproduction success of flowers and pollen transfer distances are further discussed.
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Pollinators as a subject of science education in lower secondary school
MAŠKOVÁ, Anna
This bachelor thesis is focused on pollinators as a subject of science education in lower secondary school. It includes survey of pollination, pollination syndromes and importance od the groups of insects involved in pollination. Comparative analysis of biology textbooks for lower secondary schools in terms of pollinators, pollination and results of questionnaire survey of student's knowledge on this topic. Based on this knowledge was designed a time - saving project to teach pollinators.
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Geometric morphometrics of shape and symmetry of flower structures - ecological and evolutionary significance
Rubešová, Veronika ; Neustupa, Jiří (advisor) ; Woodard, Kateřina (referee)
I did a research of relevant literature on geometric morphometrics, its usage for a study of floral symmetry, and ecological and evolutionary significance of floral symmetry in general. Description and application of morphometric methods is included in the first part of the thesis. Then, the main types of floral symmetries are described and illustrated. Morphometric studies on several model floral lineages are discussed in subsequent parts of this bachelor thesis. Many of the studies are made on some species of family Brassicaceae. Modern morphometric methods and perspectives of their application in floral research are presented in the last chapter.
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Ecology of the pathosystem of anther smut on Dianthus carthusianorum
Koupilová, Klára ; Koubek, Tomáš (advisor) ; Dostál, Petr (referee)
Anther smuts (Microbotryum violaceum s.l.) represent a well-known system for studying pathogens of wild plants and coevolution between pathogens and hosts. Infected plants produce sterile flowers with anthers filled with fungal spores which are transmitted to other host plants by pollinators. Data from existing research come mainly from the genus Silene. However, the applicability of these findings to other host plants of anther smuts is largely unknown. Therefore, this thesis focuses on a different host species - Dianthus carthusianorum. First, the pattern of disease was surveyed in natural populations of D. carthusianorum in a small area in Střední Povltaví. Most populations were infected to various degrees and only a few populations remained completely healthy. The prevalence of disease was positively correlated with size and density of host populations. On the other hand, environmental factors and the degree of connectedness had very little effect on disease prevalence. Second, additional data were collected from a subset of populations to determine plant resistance and densities of pollinators. Differences in resistance among populations (as inferred from flower inoculations) were not significant. Populations differed in densities of pollinators, but there was no correlation between densities...
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Ecology of flower smuts (Microbotryum) and their hosts from family Caryophyllaceae
Koupilová, Klára ; Koubek, Tomáš (advisor) ; Marková, Jaroslava (referee)
Anther-smut fungus (Microbotryum spp.) infecting plants of the Caryophyllaceae represents one of the most extensively studied plant pathogen systems. Anther-smut is a pollinator-borne disease that turns infected plants completely sterile. The aim of this thesis is to sum up the main findings about ecology and epidemiology of anther-smut disease and it mainly deals with various factors that influence disease spread and occurrence in nature. According to existing research, abiotic factors play minor role compared to biotic factors and interactions. Among the most pronounced, we can find variability in pathogen virulence and host resistance and also vector behaviour. When studying epidemiology of Microbotryum spp., it is necessary to take account of spatial population structure and metapopulation dynamics as well. Comparing life histories of different host species can also bring useful information. Key words: anther-smut, Microbotryum, Caryophyllaceae, pollinators, resistance, epidemiology, metapopulation dynamics.
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Diversity of bees on selected crops and their contamination by pesticides
HÝBL, Marian
Measurement of diversity and chemical contamination of bees took place at two locations. At the Zborov site, conventionally growing rape and Malonty, where it is managed in an ecological regime. At the Zborov locality, 81 individuals from 3 families, including 20 species, were captured. In addition, analyzes have confirmed the presence of pesticides in bees. In contrast, 229 individuals from 5 families, including 36 rings, were seized at Malonty. Analysis of bees in this area has rebutted the presence of pesticides.
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Beginning and duration of flowering period in selected arable weed species
Trefil, Daniel ; Holec, Josef (advisor) ; Václav, Václav (referee)
Arable weeds are usually perceived as harmfull organisms in crops. On the other hand, the weeds provide a stable source of food for insects and other invertabrates that feed on pollen and nectar. Majority of crops are not able to provide long-term food component for invertebrates because their flowering is synchronized. Arable weeds flower continously throughout the growing season. There is possible to find many flowering species for the whole year.
The main aim of the study was to determine the onset and duration time of flowering period for selected arable weed species. The observation was conducted at the Demonstration and experimental field of Faculty of Agrobiology, Food and Natural Resources neighbouring areas as well as demonstration plots with rare weed species that do not occur in fields naturally. Inventory of flowering species was performed weakly from 9th calendar week (after frost period) and finished at 48th calendar week. There were found and evaluated 160 plant species of which 67 were the rare species from demonstration plots.
First flowering weeds were photoperiodically neutral species, mainly from the group of winter annual weeds followed by ephemeral annual weeds. Among others, the late-flowering species were particulary from the group of summer annual weeds, but also some from perennial species.
During the first week of observation, 11 flowering species were found. The number gradually increased up to a maximum of 118 flowering species in the 27th calendar week; then the number of flowering plant species naturally decreased. Newly flowering species were being found until 36th calendar week. Weed differed significantly in onset of the flowering acording to perenniality, in most cases. Length of flowering period in individual species was in relation to particular families.
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Monitoring of the flowering time of selected arable weed species
Suran, Pavel ; Holec, Josef (advisor) ; Kolářová, Michaela (referee)
Flowers have an irreplaceable role in a sexual reproduction of plants. Flowers also offer the nutrients to high ammount of the insect species, both pollinators and parasitoid imagos. These insect species are depending on a beginning and a lenght of the plant flowering period and some are depending as well on a plant species diversity. Therefor it is important to monitor a flowering time of individual weed species.
The phase of the plant flowering is started, as well as by other things, by a certain temperature and a humidity. Some species might require a different value of these parameters. The beginning and the lenght of the weed flowering should correlate with a development of the temperature and the humidity during the observation period. This monitoring period was the year of 2015 and observed area was the Demontrational and experimentational land of the Faculty of Agrobiology, Food and Natural Resources of the Czech University of Life Science in Prague. During the observation period, the plant flowering times of the individual weed species were recorded on a weekly basis. In this study, the beginning and the end of the plant flowering time were evaluated for every weed species, that were observed on the observed area. Several of the observed species registered a pause in the flowering time, this pause was also evaluated. It was found out, that most of the species, that start flowering in the spring, started flowering roughly one or two months earlier. The plants capable of flowering during a moderate freezes flowered untill the very late autumn or even during november. The plant species, that start thein flowering in the summer were not affected by an increase in the temperature of the first months, but they were affected by the very high summer temperatures and these species stopped flowering and they either never flowered again, or they started flowring, once the temperature dropped.
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Meaning and contemporary situation in beekeeping
TUPÁ, Kateřina
This thesis is concerned by importance and current situation in breeding of bees. At first, thesis briefly describes characteristics of Honeybee (Apis mellifera) and its life cycle. At second, thesis summarizes information about ambitiousness of human work dedicated to breeding of a bee and manipulation with hive, which protective equipment is needed. At third, thesis points out the problematic caused by adverse effects like pests, diseases or mankind. Last but not least thesis deals with quality and production of bee products and current situation of beekeeping in the Czech Republic. Beekeeping is one of the oldest branches of human activity and in peoples' free time its importance is not small. Moreover, beekeeping has very important position in agriculture as a source for pollination of insect-pollinated and cross-pollinated plants, where it helps to increase the yields. Next, it has great importance in the branch of foods, mostly thanks to the production of honey. All of the bee products are highly prized in the pharmaceutical, healthcare and glass industry, where they are parts of nourishing and moisturizing preparations, medicaments and firming cements. Quality of hives is given by the experience of beekeeper and the possibility of financial support by grants assigned by Ministry of Agriculture of the Czech Republic. The objective of the thesis is to point out the importance of Honeybee in our landscape and to highlight the significance and quality of bee products. The researches show that the beekeeping is ib the Czech Republic on very high level, but there is lack of beekeepers.
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