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This thesis deals with a survey of provenance areas and assessment of attacking Fraxinus excelsior L. and Fraxinus angustifolia by the pathogen Hymenoscyphus fraxineus. The aim of the thesis is to map the incidence of infected trees in these areas and to evaluate the sensitivity of the sites to the pathogen Hymenoscyphus fraxineus. The theoretical part deals with processing of data collected during field work on selected provenance areas Koneprusy and Veltruby. Amongst the evaluated parameters there were: trunk diameter at measuring height, tree height, and especially canopy drying caused by Hymenoscyphus fraxineus. As the outcome of the survey photographs were taken and records were collected for individual trees in the provenance areas. Each of the trees has its own unique label that has accurately defined its location to prevent potential errors in data processing. The processed data was then evaluated in NCSS 8.0 software and cluster analysis was performed in order to compare the provenances. This analysis only compares the provenances, which are located in both provenance areas. The results show that no provenance without the pathogen Hymenoscyphus fraxineus attack appeared in the provenances Koneprusy and Veltruby. Subjects in 4 ŠLP Kostelec nad Černými Lesy - Svojšice and 24 LS Czech Krumlov Chvalšiny proved to be more resistant than others. Although the increase in the tree height and the trunk thickness is the largest on those areas the defoliation rate is high. It is probable that the population of these provenances will gradually die. Due to growing abbility of some individuals located in other provenances it is obvious that habitat conditions and individual resilience are key factors. |
