Lichenofágia na pozadí sekundárnych metabolitov

• Thesis title in thesis language (Slovak): Lichenofágia na pozadí sekundárnych metabolitov
• Thesis title in Czech: Lichenofágie na pozadí sekundárních metabolitů
• Thesis title in English: Mollusc grazing and secondary metabolites of lichens
• Key words: měkkýši, lišejníky, herbivorie
• English key words: molluscs, lichens, herbivory
• Academic year of topic announcement: 2010/2011
• Thesis type: diploma thesis
• Thesis language: slovenština
• Department: Department of Botany (31-120)
• Supervisor: RNDr. David Svoboda, Ph.D.
• Author: hidden - assigned by the advisor
• Date of registration: 16.11.2010
• Date of assignment: 16.11.2010
• Date of electronic submission: 06.05.2013
• Date of proceeded defence: 27.05.2013
• Opponents: doc. Jan Vondrák, Ph.D.

Preliminary scope of work in English

Although epiphytic lichen communities are thought to be mainly shaped by climatic factors, herbivory may also play a?significant role. The aim of my study is to find out a?relationship between the grazing pressure from molluscs, the content of secondary metabolites and the lichen species position on tree trunks.
Lichen secondary compounds, especially those in medulla might serve as their herbivore defence. Their concentrations will by measured by the means of HLPC.
To test the herbivore defence role I will provide molluscs with a choice between thalli free of the secondary compounds resulting from acetone rinsing and control thalli. For comparison, the thalli will be weighed and photographed both before and after the experiment.
In order to determine the natural height distribution range of the lichen species I?will climb trees and note the position of the lowermost and the uppermost thallus of each species.
I will also design a transplantation experiment to test the potential effect of herbivory on the lower distribution level on the tree trunks. The thalli of all the species will be randomly attached onto nylon meshes and these will be placed onto trunks of Acer pseudoplatanus at 3 heights (0,5 m, 2 m, 6 m). Again, the thalli will be weighed and photographed both before and after the experiment.