Search for dissertations about: "UV B STRESS"

Showing result 1 - 5 of 17 swedish dissertations containing the words UV B STRESS.

2. 1. Vitamin B6 as a potential antioxidant : a study emanating from UV-B-stressed plants

   Author : Mikael Ristilä; Åke Strid; Leif Eriksson; Éva Hideg; Örebro universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; Arabidopsis; UV-B irradiation; pyridoxine; vitamin B6; ROS; Chemistry; Kemi; Chemistry; Kemi;

   Abstract : Increased influx of solar UV-B radiation (280-320 nm), due to a decreasing stratospheric ozone layer, impacts severely on plants. Some of the UV-B effects on plants are related to stress induced by produced reactive oxygen species (ROS). Pyridoxine (vitamin B6) has been reported to be a potential quencher of ROS. READ MORE

4. 2. Ecophysiological responses of Baltic and Atlantic Fucus vesiculosus to environmental factors

   Author : Charlotta A Nygård; Nils Ekelund; Mittuniversitetet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; acclimation; Atlantic; Baltic Sea; Bothnian Sea; Cd; Fucus vesiculosus; growth; high PAR; Pb; photosynthesis; salinity; stress; UV-B; Biology; Biologi;

   Abstract : The Baltic Sea is a species-poor ecosystem where marine species coexist with freshwater species. The Baltic Sea offers low salinity, low content of inorganic carbon, long cold winters and no tides. READ MORE

5. 3. Modification of flavonoid content and photosynthesis by ultraviolet-B radiation. Atrazine-tolerant and -sensitive ultivars of Brassica napus

   Author : Louise Olsson; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; recovery; quercetin; photosynthesis; photoinhibition; photoacoustics; leaf anatomy; kaempferol; flavonoid; D1 protein; fluorescence; cold stress; carbon dioxide; atrazine tolerance; Brassica napus; UV-B; Physiological biophysics; Växtfysiologi;

   Abstract : Levels of ultraviolet-B (UV-B, 280-320 nm) radiation reaching the Earth´s surface increase due to stratospheric ozone depletion. In this thesis the effect of enhanced UV-B radiation was studied on the atrazine-tolerant mutant Stallion, susceptible to photoinhibition, and the atrazine-sensitive cultivar Paroll of Brassica napus (oilseed rape). READ MORE

6. 4. Evolutionary ecology of ultraviolet-B radiation stress tolerance in amphibians

   Author : Maarit Pahkala; Trevor Beebee; Uppsala universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; amphibians; anomalies; embryonic development; geographic variation; growth; Rana arvalis; Rana temporaria; survival; UV-B radiation; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; populationsbiologi; Population Biology;

   Abstract : During the last decades many amphibian species and populations have experienced declines and extinctions in different parts of the world. Anthropogenic activities are believed to account for these declines, and one of the hypothesized causes has been the increased level of ultraviolet-B (UV-B) radiation due to depletion of the stratospheric ozone layer. READ MORE

7. 5. Molecular responses of plants to solar UV-B and UV-A radiation

   Author : Luis Orlando Morales; Pedro José Aphalo; Mikael Brosché; Riitta Tegelberg; Nigel Paul; Örebro universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; Biology; Biologi;

   Abstract : Plant responses to solar ultraviolet radiation (UV, 280-400 nm) were assessed at different molecular levels using Betula pendula Roth (silver birch) and Arabidopsis thaliana (Arabidopsis) as model species in outdoor experiments to assess the possibly interacting roles of the UV-B and UV-A wavebands in acclimation to sunlight. Solar UV-B (280-315 nm) and UV-A (315-400 nm) irradiance was attenuated with plastic films. READ MORE