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Ability to Discriminate Floral Morphotypes by Hoverflies
Matoušková, Eva ; Janovský, Zdeněk (advisor) ; Klečka, Jan (referee)
The attractiveness of flowers to pollinators is mediated by several floral traits. The ability to discriminate the flowers based on these floral traits is crucial for the flower reproduction and pollinator nutrition and reproduction. We tested three floral traits - colour, size and shape - along with their combinations using artificially 3D printed flowers on model organism Eristalis tenax in laboratory conditions. Our findings revealed that the most important floral trait was the colour followed by size. Additionally, the effect of colour was enhanced by size, but only for the preferred colour. This suggests that preferences for specific floral traits can be structured. The effect of symmetry was not significant. Subsequently, we observed non-naïve hoverflies and bumblebees in the field on flower patch consisting of devil's-bit scabious (Succisa pratensis). We were interested in the role of other floral traits when the colour and size were indistinguishable. The most important characteristics were height and effective number of florets in the inflorescence. The hoverflies tend to do longer visits than bumblebees and visited more flowers as well. Conversely, bumblebees did shorter but more efficient visits, likely due to their eusociality. Keywords: Syrphidae, Apidae, Eristalis tenax, Bombus spp.,...
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The Origin and Function of Heterostyly in Angiosperms
Nainar, Adam ; Münzbergová, Zuzana (advisor) ; Slovák, Marek (referee)
This bachelor's theses focuses on the phenomenon of heterostyly, which is an extraordinary feature of several representatives of plants from Angiosperm group like primroses /Primula/, based on two or three simultaneously occuring forms of one species, and expresses itself by opposite height configuration of anthers and stigmas, and that supports a reciprocal pollination and decreases a risk of self-pollination. The introduction in the beginning of the theses compares heterostyly with another various adaptations, which Angiosperms use them to avoid self-pollination. Further, the theses is divided to topical chapters, such as occurence and types of heterostyly (distyly, tristyly), and there are also many mentions about history of research of this phenomenon and about possibilities, according to which the heterostyly could have been evolved. In the theses there are mentioned other supplementary features, such as pollen grain differences as well. Also, this theses dedicates to interactions between heterostylous plants and pollinators and even to a brief genetic basis of heterostyly, which is a very important topic for explaining all these features. In the conclusion, there is mentioned a project named "The chase for cowslips", which is mapping populations of primroses - cowslips /Primula veris/ in...
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The Effect of Presence and Abundance of Parasites (Nomada, Stylops) on the Host Species Population (Hymenoptera: Andrena) at the Level of Entire Communities
Bureš, Vít ; Straka, Jakub (advisor) ; Libra, Martin (referee)
Bees (Anthophila) play a crucial role as pollinators, vital for maintaining biodiversity in ecosystems. However, the decline in pollinator populations in recent years raises concerns about ecosystem stability. This study investigates the impact of parasitism on host bee populations of the genus Andrena as a potential factor influencing the decline of insects. Additionally, it examines populations of parasites of the genera Stylops and Nomada as indicators of host population status. Bees of the genus Andrena are abundant in the western Palearctic and are commonly parasited by Stylops and Nomada. Leveraging a large dataset from Europe, this study uses abundance data to explore the influence of abiotic and biotic factors on the parasitization rates of host Andrena bees. Specifically, the effects of abiotic factors such as altitude, habitat type, annual rainfall, and average temperature on the parasitization rates by both parasite types has not been confirmed. The results indicate that within small geographical units (sites), larger populations of host Andrena bees are more heavily parasitized by Stylops compared to smaller populations, while this trend does not hold true for Nomada. Interestingly, this study reveals that Stylops and Nomada coexist within the same host populations without competing for...
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Education of preschool children in the topic of honey bee as an important pollinator.
MERIKOVÁ, Jitka
Presented bachelor thesis was focused on creating a range of educational activities within the framework of environmental education, the aim of which was to raise the awareness of preschool children about the importance of the honey bee as our important pollinator. The main emphasis was placed on a playful form of activities that are intended to arouse children's interest in learning in the given area and, using experiential learning methods, to realize the importance of pollinators for our society and humanity as such. Basic pedagogical terms and terminology were defined in the theoretical part. Another part of the bachelor's thesis was devoted to the origin of the honey bee, its biology and morphology. An integral part of this literary part, a description of the principle of pollination, its impact on food production and environmental biodiversity. In the Practical part, activities focused on a playful form of experiential learning was presented. The presented activities were implemented in a kindergarten in South Bohemia and are described in detail. The program was subjected to reflection, which evaluated the impact of educational offers on children in kindergarten.
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Evolutionary forces of Central European taxa of the genus Dactylorhiza
Bílá, Klára ; Urfus, Tomáš (advisor) ; Figura, Tomáš (referee)
Genus Dactylorhiza, comprising green terrestrial orchids, belongs to of the most taxonomically complex groups of Europeran flora. Basic species often hybridise between each other and there is a lot of taxonomically challenging hybrids and hybridogenous lineages. Essential parental species of majority of hybrids and hybridogenous lineages are D. incarnata, D. maculata and D. fuchsii. Sister genus of Dactylorhiza is Gymnadenia which shares some similar features with Dactylorhiza species. Dactylorhiza viridis, formerly classified into the genus Coeloglossum, is the earliest diverged species. Diversity centre probably takes place in the Mediterranean Basin from where Dactylorhiza species migrated back to the Central Europe in postglacial. Major force of the genus evolution is polyploidisation which together with hybridisation leads to establishment of allopolyploid lineages. Unique feature of many orchids (including genus Dactylorhiza) is partial endoreduplication, which somatic endopolyploidisation of certain part of genome takes place. Pollination type is also important for Dactylorhiza microevolution. Deceptive flowers of Dactylorhiza genus are mainly pollinated by naive bumlebees but even beetles or ants can be pollinators. Majority of Dactylorhiza species are threatened by habitat loss during last decades....
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Floral biology of tropical alpine plants
Holzbachová, Lucie ; Sklenář, Petr (advisor) ; Ptáček, Jan (referee)
Tropical alpine environments are characterised by specific environmental conditions to which the local plants adapted through evolution. The specificity is especially in a strong diurnal climate with temperatures falling below zero at nights. At the same time, this environment lacks thermal seasonality, which allows growth and flowering throughout the year. While floral biology is relatively well described in temperate regions, it has only been studied sporadically in the tropics. This study summarises the knowledge of floral biology in tropical alpine environments with a focus on zoophily plants. The principal part of this work is dedicated to floral traits, focusing on flowering phenology, which is diversified for every species during the year. In this way, plants face competition, especially for their pollinators, which decrease in abundance with altitude. Although not all phenological strategies have been studied so far, we can find several main flowering schemes. This literature review points to unexplored research topics about floral biology of plant inhabiting tropical mountains that might provide a basis for future studies.
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Dynamics of pollination networks in time and space
Matějková, Zuzana ; Hadrava, Jiří (advisor) ; Tropek, Robert (referee)
This bachelor's thesis focuses on changes in pollination networks on different spatio-temporal scales. It covers in detail the essence and magnitude of these changes in communities of pollinators and plants. The thesis outlines the consequences of these changes for these communities and the way it affects the methodological aspects of studying plant-pollinator networks. I present the existing dynamics of Pollination networks on broad geografical scales as well as changes in local communities. I also describe the temporal changes of communities of plants and pollinators, consisting of diurnal and seasonal dynamics, not exluding the changes on even broader temporal scales. It has been shown that plant-pollinator networks are highly dynamic in space and time. These dynamics consist of species and interaction turnover, as well as of changes in the overall diversity of communities of plants and pollinators. Biodiversity dependent characteristics of pollination networks are affected by the described spatio-temporal dynamics, while characteristics that are biodiversity independent stay relativly stable on broader temporal scales.
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The Competition Among Pollinators and the Impact of Managed Bees on Wild Pollinator Populations
Voldřichová, Alžběta ; Straka, Jakub (advisor) ; Štenc, Jakub (referee)
Pollinators play an important role in ecosystems. Their ties to plants are essential for the reproduction of many plant species and thus for the protection of species diversity. Pollinator species therefore need to be protected. But to protect them effectively, it is necessary to understand the relationships between pollinators. However, the interaction between pollinators is a complex topic that needs further research. One of the current threats to pollinator populations is commercial pollinator rearing. Commercially reared species, especially Apis mellifera and Bombus terrestris, have been introduced almost all over the planet due to their positive effects on crop yields and its by-products. Moreover, in their native ranges they are bred in much higher concentrations than would be possible without human intervention. But high concentrations of commercial pollinators do affect populations of wild ones. This thesis describes forms of pollinator competition and addresses the impact of commercially reared pollinators on wild pollinator populations. KEY WORDS: Honeybee - Bumblebee - Hoverfly - Nest usurpation - Pathogen transfer - Species protection - Invasive species
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Possibilities of implementation of the pollination as the pedagogical content of the elementary schools
MAŠKOVÁ, Anna
The diploma thesis focuses on pollinators as a subject of science education and especially the possibility of implementation in teaching at primary school. The research part deals with pollination, the importance of pollinators, anchoring the topic in the Framework Educational Program, and especially the analysis of several textbooks of science for primary schools in terms of the topic of pollinators. To obtain the necessary data in the practical part, didactic tests and an educational project for the pupils of 4th and 6th grade at primary schools were created. Based on the acquired findings, a conclusion was drawn regarding the possible inclusion of the topic in teaching at primary school.
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Reproductive success in pollinating deceptive orchids
Steffelová, Michaela ; Kindlmann, Pavel (advisor) ; Janeček, Štěpán (referee)
One third of plant species in the Orchidaceae family use a deceptive strategy to fool pollinators. There are many strategies for deceiving orchids, and each has its advantages and disadvantages. Reproductive success is a quantity usually defined as the ratio of the number of fruits to the number of flowers produced by the plant during a given season. It is influenced by many factors. This work is written in the form of a literature review and deals with the factors that influence the reproductive success of deceptive orchids in connection with their pollination. The reproductive success of the orchid depends mainly on the density of the inflorescence, the time of flowering or the place where the plant is located. These factors in turn affect the pollinators, who are largely responsible for the orchid's reproductive success. The specialized strategies of deceptive orchids lead to a decrease in the reproductive success of an individual, but a low population density or lower pollinator attendance at one inflorescence, on the contrary, lead to an increase in the reproductive success of a deceptive orchid individual. Deceptive orchids do not use a strategy that is clearly disadvantageous, so it is unlikely that the orchid will become extinct in the future due to its pollination strategy. Key words:...
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