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The efficiency of pollen transfer by selected functional groups of pollinators and the ability of plants to influence it
Freudenfeld, Martin ; Janovský, Zdeněk (advisor) ; Klečka, Jan (referee)
Pollinator functional groups differ in their pollen carryover effectiveness and in the importance for particular species of plants, due to specific functional traits of pollinator functional groups. Plant species differ in their specific functional traits too. I determined pollen loads of pollinators by swabbing their bodies with a jelly to compare pollen carryover effectiveness of pollinator functional groups. This helped me to decide which pollinator functional groups are the most and the least effective in pollen carryover. I considered an influence of the last visited flower to make the comparison of pollen loads more accurate. I also calculated proportions of conspecific and heterospecific pollen grains carried on bodies of pollinators to estimate their carryover effectiveness. Likewise, I compared composition of pollen morphotypes carried on pollinator's bodies to find out differences among pollinator functional groups. My analysis shows that pollen carryover effectiveness of particular pollinator functional groups differ. Apis mellifera and solitary bees have the biggest pollen loads, on the other hand, butterfies and small dipterans have the smallest pollen loads. The last visited flower influences an amount of pollen grains carried on bodies of pollinators. Relative pollen loads of some...
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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 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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Evolutionary significance of visual traits of flowers and their influence on the pollinator constancy
Haveldová, Alice ; Štenc, Jakub (advisor) ; Klečka, Jan (referee)
Flower constancy is a behavior in which the pollinator visits flowers of the same plant species in a sequence more than would correspond to its preference for the given plant. This behavior is advantageous for plants because it can ensure efficient intraspecific pollen transfer which has a positive effect on their biological fitness. More efficient pollen transfer can lead to the selection of (visual and olfactory) flower traits that encourage flower constancy of pollinators. The main visual floral traits that affect constancy include colour, pattern, shape and size. However, these traits are of different importance for pollinators when they are deciding which flower to visit, and therefore their effect on flower constancy varies. The degree of flower constancy also differs between the functional groups of pollinators. Flower constancy is generally low in vertebrates, but insects and especially representatives of the order Hymenoptera are often flower constant.
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The importance of the arrangement of flowers in the inflorescence on the plant reproductive success
Chvojková, Karolína ; Štenc, Jakub (advisor) ; Sklenář, Petr (referee)
Inflorescence and its properties have a fundamental influence on the pollinating behavior of pollinators, which can affect the resulting reproductive success of plants. Clustering of more flowers in the inflorescence is an advantage for plants due to the diversification of pollen sources and greater visual supply, which can attract more pollinators and thus increase the chance of pollen transfer to other individuals and ensure genetic variability of the offspring. The disadvantage of multiple flowers in one inflorescence may be both an increase in energy requirements for the formation and maintenance of multiple flowers and an increased risk of geitonogamy. Plants prevent geitonogamy within the inflorescence by various adaptations. The aim of this work is to evaluate the effect of inflorescence arrangement on successful plant reproduction. When studying the arrangement of flowers in the inflorescence, it is necessary to take into count not only their morphology, i.e. the shape, number, size and arrangement of flowers, but also other functional properties in the form of genitals, sterility and rewards. The resulting effect of flower arrangement on the reproductive success of plants also depends on the vectors that transfer pollen, in this case especially insect pollinators, which are affected by...
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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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Selected Meadow Pollinators and Their Didactical Use
Huňková, Helena ; Říhová, Dagmar (advisor) ; Hanel, Lubomír (referee)
This Master thesis is focused on selected pollinators of our meadows and their didactic integration into education. The thesis is divided into two parts - theoretical and practical. In theoretical part, there are defined two orders (Hymenoptera and Diptera), process of pollination, plants pollination strategies and pollen grain. Practical part is focused on research of dipterans (particularly on hoverflies) of which purpose was to find out which plants are most pollinated. Subsequent section deals with analysis of secondary school Biology textbooks in terms of representation of selected pollinators. Next section contains plan of practical exercise, which deals with whether honey contains pollen grains. In final section of practical part, a worksheet is presented, which verifies pupil's knowledge about pollinators. KEYWORDS Hymenoptera, Diptera, hoverfly research, pollinators, pollen, textbook analysis
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