|
| |
|
|
Plant-Animal Interactions in an Inselberg Ecosystem: The Effect on Reproduction of Selected Species
Vlasáková, Blanka ; Sklenář, Petr (advisor) ; Porembski, Stefan (referee) ; Jersáková, Jana (referee)
Conclusions This thesis provides detailed insight into plant-animal relationships that are involved in reproduction of inselberg species. The results are interpreted in relation to the ecosystem functioning and they also contribute to the general knowledge on specialization in plant-animal interactions (Chapter 2 and 3), floral resources (Chapter 2, 3, and 5), pollinators' attraction (Chapter 2), relations between diaspore's characteristics and animal dispersal (Chapter 4), and conflicts among plant life stages that follow ovule fertilization (Chapter 4). As Clusia aff. sellowiana dominates the shrub vegetation, the study on its reproduction is the initial step to understanding the dynamics of the shrub patches and potential succession on the inselberg. The nocturnal pollination system of Clusia aff. sellowiana bears unusual characteristics and signs of specialization. Only one pollinator species, a cockroach Amazonina platystylata, was recorded and this species is apparently sensitive to olfactory attraction cues emitted by the flowers. This is the first evidence of pollination system that involves cockroaches as pollinators and is to some degree specialized. Clusia aff. sellowiana is dispersed by small birds. Because its diasporas are consumed by birds and there is a time lag before they are deposited,...
|
|
| |
|
|
Pollination of Clusia blattophila: Quality and quantity components of the plant-pollinator system
Pinc, Jan ; Vlasáková, Blanka (advisor) ; Chrtek, Jindřich (referee)
This work discusses the pollination system of Clusia blattophila on the Nouragues inselberg in the central part of French Guiana. The pollination system is unique, because one of the pollinators is probably a cockroach species, Amazonina platystylata. It is the third, and the last known case of cockroach pollination. Flowers are also visited by crickets (Gryllidae), flies (Diptera) belonging to the families Hybotidae, Cecidomyiidae, Dolichopodidae, and some other arthropods. This work deals with the effectiveness of the pollination system and its two components. The quantitative component of the pollination effectiveness is characterized by the number of visits and visit duration. A qualitative characteristic of pollination is characterized by the number of pollen transferred by individual pollinator. To determine quantitative characteristics, ca. 450 hours of recordings were taken. From the recordings, it is apparent that cockroaches and dipterans occur on flowers more frequently, and also that cockroaches and crickets spends on flowers more time. To determine the quantitative characteristics, pollen load on stigma and insect was determined and an exclusion experiment was performed when only some floral visitors were allowed to touch the flowers. All experiments confirm that cockroach Amazonina...
|
|
|
Plant-pollinator relationships in isolated ecosystems and ecosystems with extreme fluctuations in climatic conditions
Pinc, Jan ; Vlasáková, Blanka (advisor) ; Vazačová, Kristýna (referee)
In extreme and isolated ecosystems, organisms are often specifically adapted to local abiotic conditions due to relatively fast-moving diversification and strong selection pressure. Their mutualistic relationships are very often quite unusual and unique. Plants grow in populations with a limited number of individuals. They are exposed to strong selection pressure for outcrossing to minimize the loss of genetic variability due to inbreeding, which is common in small populations. Maximizing outcrossing usually results in various modifications of pollination systems. These modifications are affected by the insufficient number of potential pollinators and by their irregular occurrence. The aim of this paper is to summarize the typical features of pollination systems in extreme and isolated ecosystems and to clarify the conditions that led to their creation.
|
|
|
Plant-Animal Interactions in an Inselberg Ecosystem: The Effect on Reproduction of Selected Species
Vlasáková, Blanka ; Sklenář, Petr (advisor) ; Porembski, Stefan (referee) ; Jersáková, Jana (referee)
Conclusions This thesis provides detailed insight into plant-animal relationships that are involved in reproduction of inselberg species. The results are interpreted in relation to the ecosystem functioning and they also contribute to the general knowledge on specialization in plant-animal interactions (Chapter 2 and 3), floral resources (Chapter 2, 3, and 5), pollinators' attraction (Chapter 2), relations between diaspore's characteristics and animal dispersal (Chapter 4), and conflicts among plant life stages that follow ovule fertilization (Chapter 4). As Clusia aff. sellowiana dominates the shrub vegetation, the study on its reproduction is the initial step to understanding the dynamics of the shrub patches and potential succession on the inselberg. The nocturnal pollination system of Clusia aff. sellowiana bears unusual characteristics and signs of specialization. Only one pollinator species, a cockroach Amazonina platystylata, was recorded and this species is apparently sensitive to olfactory attraction cues emitted by the flowers. This is the first evidence of pollination system that involves cockroaches as pollinators and is to some degree specialized. Clusia aff. sellowiana is dispersed by small birds. Because its diasporas are consumed by birds and there is a time lag before they are deposited,...
|
|
|
Sustainable agrotechnical advancement: Crop yield increase caused by natural stimulants
Vlasáková, Blanka ; Albrechtová, Jana ; Bartoš, M. ; Frantík, Tomáš ; Horna, A. ; Koblihová, Helena ; Kotyza, P. ; Kovářová, Marcela ; Látr, A. ; Nývltová, Z. ; Pilařová, M. ; Vazačová, Kristýna ; Vosátka, Miroslav
Based on a number of experiments, mostly field ones, positive effects of the described natural stimulants are used to increase utility value and yield properties of selected crops and offered as a non-risk, environment-friendly agricultural chemicals
|
|
| |
guest ::
