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Physiological status of young silver fir on stands with different microclimate using biochemical, and optical needle traits.
Kabilková, Eva ; Lhotáková, Zuzana (advisor) ; Pokorný, Radek (referee)
Silver fir (Abies alba Mill.) is a candidate tree species in the process of forest transformation especially of spruce monoculture stands (Picea Abies (L.) H. Karst.), thanks to its better growth characteristics in conditions of mild drought. However, fir, as a very shade tolerant tree, may be more susceptible to various abiotic stressors in more open forest canopies, and therefore it is necessary to study its ecological requirements in connection with the most effective possible application in forestry. In this thesis, the physiological state of young fir stands affected by different light microclimatic conditions, which were represented by different types of forest regeneration, was studied. Specifically, it is shelter-wood cut, which represents the likely highest degree of shading by mature trees, then natural regeneration under sparse canopy, gap cut and small clear cut, which represent a moderate degree of shading by mature trees, and last but not least, clear cut, which represents the lowest degree of shading. Physiological status was evaluated using biochemical and optical properties of the needles, and additional microclimatic conditions of the habitats, namely temperature and soil moisture, were also evaluated. Our results showed that the used biochemical and optical properties of the...
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Plant responses to low temperatures, resistance and damage
Kabilková, Eva ; Prášil, Ilja (advisor) ; Hála, Michal (referee)
Plants can encounter many stressors throughout their lives, including low temperatures. This work characterizes the limits of extreme temperatures that have an effect on plants; cold (temperatures ranging from 0 ř C to 15 ř C) and frost (temperatures below 0 ř C accompanied by ice formation in plant tissues). Consequences of plant damage caused by extreme temperatures are also given, as well as the most important plant resistance and defense mechanisms in response to these stressors, especially at the cellular level. These are temperature responding signalling transduction pathways leading to the activation of stress genes and some phytohormones (abscisic acid, salicylic acid, jasmonates), as well as the accumulation of stress proteins (e.g. anti-freezing proteins, dehydrins). At the same time, some of the impacts of climate change, including global warming, on selected plants species are mentioned. Key words: stress, plants resistance, tolerance, low temperature, cold, frost, damage to plants
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