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Potential of genetic engineering for breeding plants tolerant to abiotic stresses: cold resistance in rice
Lotová, Gabriela ; Lipavská, Helena (advisor) ; Janská, Anna (referee)
With increasing population and climate change, there has been an increase in efforts to breed more efficient crops. Genetic engineering has opened unprecedented breeding possibilities in developing plants with desired traits. Transgenic crops with better qualities, including resistance to adverse environmental conditions, can contribute to solving problems of hunger and malnutrition in developing countries. Although society perceives genetically modified crops rather negatively, these crops are widely used as feed for livestock and outside Europe also for human nutrition. Because of the complexity of resistance to abiotic stress, the utility of genetic manipulations for the breeding of resistant plants was previously not anticipated. However, it turned out that modification of the stress signalling cascade or transcription factors can lead to success. This thesis summarizes the possibilities of genetic modification of crops, which may result in better tolerance to cold, and is mainly focused on rice. Part of the work deals with transduction of cold signal, whose modification can also result in increased tolerance to cold. Another part deals with transcription factors that activate expression of low temperature- resistant genes. The greatest attention is paid to CBF/DREB transcription factors that...
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Oxidative stress level as a marker of stress memory in selected genotypes of potato Solanum tuberosum ssp. tuberosum and ssp. andigena
Lotová, Gabriela ; Mašková, Petra (advisor) ; Lhotáková, Zuzana (referee)
Plants are exposed to the stress of the environment throughout their entire live. They therefore had to develop sophisticated mechanisms to avoid or tolerate stress. In some plants, repeated exposure to stress increases tolerance, which is known as stress memory. The aim of this study is to assess stress memory in terms of oxidative stress level. Content of malondialdehyde (MDA), reactive oxygen species (ROS) and the electrolyte leakage were chosen as markers of oxidative stress. Fresh weight, plant height and water content were also evaluated. The level of oxidative stress was assessed in several genotypes of Solanum tuberosum subspecies, Andigena and Tuberosum. In vitro culture did not work well for the evaluation of stress memory, ex vitro partially did. The content of MDA in 66B was significantly lower than in cv. Lada (Tuberosum) in root (in vitro) and shoot (ex vitro) in control groups as well as during water shortage. Treatment of acclimation-inducing cold before the stress-inducing cold had a variable effect on growth and electrolyte leakage according to the culture conditions. In vitro, the effect on electrolyte leakage in roots of cv. Lada was positive, in leaves of 66B (Andigena) it was negative. In ex vitro, a positive effect was found on electrolyte leakage in 66B leaves, but at the...
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Potential of genetic engineering for breeding plants tolerant to abiotic stresses: cold resistance in rice
Lotová, Gabriela ; Lipavská, Helena (advisor) ; Janská, Anna (referee)
With increasing population and climate change, there has been an increase in efforts to breed more efficient crops. Genetic engineering has opened unprecedented breeding possibilities in developing plants with desired traits. Transgenic crops with better qualities, including resistance to adverse environmental conditions, can contribute to solving problems of hunger and malnutrition in developing countries. Although society perceives genetically modified crops rather negatively, these crops are widely used as feed for livestock and outside Europe also for human nutrition. Because of the complexity of resistance to abiotic stress, the utility of genetic manipulations for the breeding of resistant plants was previously not anticipated. However, it turned out that modification of the stress signalling cascade or transcription factors can lead to success. This thesis summarizes the possibilities of genetic modification of crops, which may result in better tolerance to cold, and is mainly focused on rice. Part of the work deals with transduction of cold signal, whose modification can also result in increased tolerance to cold. Another part deals with transcription factors that activate expression of low temperature- resistant genes. The greatest attention is paid to CBF/DREB transcription factors that...
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