In this master thesis, we investigated the effect of experimentally induced drought on the composition and viability of the ectomycorrhizal fungal community (ECM) of downy oak (Quercus pubescens Willd.) in an experiment at the Karst (SW Slovenia). For the experiment, we selected four plots of approximately100 m2 with downy oak as the dominant tree species, two of which were control plots and two of which were under increased drought stress. For this purpose, gutters were placed under the tree canopies, which largely diverted rainwater away from the root zone of the studied trees. ECM composition and vigour were determined in selected plots before and one year after the start of the drought experiment by sampling oak roots. No differences in mycorrhizal fungal viability were observed between the two sampling years orbetween the drought and control plots. We also found no significant differences in population of mycorrhizal fungi between the drought and control plots , either at the level of morphotypes or at the level of molecularly identified ECM species, but we did observe an increased presence of the fungus Cenococcum sp., which is characteristic for stress conditions. This suggests that the ECM fungal community studied is so resilient that significant differences in the community are not yet evident within a short period of time after the start of the drying process, but that a longer experimental period is required.
|
