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Uptake of heavy metals - the role of the root system
Homola, Adam ; Tylová, Edita (advisor) ; Mašková, Petra (referee)
Heavy metals are important soil pollutants and pose a significant risk to plants under certain conditions. These include some essential microelements (Fe, Zn, Mn, Mo, Cu, Ni) and toxic metals (e.g. Cd, As, Pb, Hg). Essential microelements have important functions in plants, and are mainly involved in plant metabolism as cofactors of enzymes. Toxic metals have no function, yet they enter the plant in varying degrees from the environment and cause toxicity. However, excessive concentrations of essential metals in the plant also have negative effects and plants have different mechanisms to counteract these negative effects. The bachelor thesis focuses mainly on the uptake of heavy metals from the soil by the root, which is achieved by membrane transporters. It also discusses several mechanisms involved in defence against heavy metal toxicity, not only in terms of regulating uptake, but also after heavy metals have entered plant bodies. These mechanisms are an important aspect of hyperaccumulation, which is also included in this thesis. Hyperaccumulators use these mechanisms on a completely different scale than non-hyperaccumulators, which allows hyperaccumulators to live in environments where heavy metal concentrations are high, making them completely different from each other. The properties of...
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Role of metal hyperaccumulation in serpentine adaptation
Havlíková, Karolína ; Kolář, Filip (advisor) ; Stiblíková, Pavlína (referee)
Throughout our planet's history, plant and organism communities have faced many severe environmental challenges. Changing environment forces leads to the adaptation of plants to specific conditions, such as serpentine soils, specific by their natural toxicity. There are several possible adaptation mechanisms to serpentine challenges and one of them is probably hyperaccumulation. Hyperaccumulation is the ability of a plant to accumulate large amounts of heavy metals without signs of toxicity, and most such plants live on serpentine soil. However, it is far from known how many plants have such an ability. Some plant species inhabit normal soils as well as serpentine soils. These so-called facultative hyperaccumulators represent ideal study systems for addressing the role of hyperaccumulation the adaptation towards toxic soils. These species are most often found in the Brassicaceae family and also in the genus Alyssum s.l.. So far understudied species Alyssum gmelinii may be one of these promising new model species as it grows on a normal substrate, as well as on a serpentine. My bachelor thesis tries addresses the role of hyperaccumulation in substrate adaptation both theoretically and in a practical experiment with replicated natural populations of A. gmelinii. Two serpentine and two non-serpentine...
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Study of physiological changes in plants under stress by zinc ions
Adam, Rostislav ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals are part of us life for many centuries. Some of them are for living organism neccessary, but in large amount they have toxic effects. So we should decrease amount of heavy metals in the Environment. We have many way to do it. A relatively new way are the phytoremediation. If we would use the phytoremediation, we should know, what they do in plants. We must use specific plants, which are tolerant to certain heavy metal. If we would select a suitable plant, we have to try, how heavy metals in soil solution are toxic to plants. Zinc is no expection, although it is important part of many proteins. In plants it make rusty leaves and reduct aboveground and root biomass production. In hydroponic experiment I investigated that mallow Malva verticillata was very sensitive to low additon of Zn(NO3)2. The toxic efect appeared in 2 weeks. In sorghum Sorghum bicolor zinc show expressive toxic effect at concentration 1 mmol/l. I studied six cultivars of Sorghum bicolor, DSM 14-535, Expres, Honey Graze BMR, Nutri Honey, Sucrosorgho 506 and Sweet Virginia. According EC50 I as- sessed that the most sensitive was Sucrosorgho 506 and very tolerant were Nutri Honey and Sweet Virginia. Cultivar Nutri Honey was characteristic. It had the highest ratio concentration in shoot to concentration in root. I studied...
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Mechanism of uptake of heavy metals and organic compounds by plants
Berkyová, Petra ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals and organic compounds represent a great problem for environment. Therefore, attention is paid to the development of techniques for removing these pollutants from the sites of pollution. One of the possibilities is that heavy metals and organic compounds are removed from soil by using fytoremediation. Fytoremediation uses the ability of some plant species to uptake toxic compounds from soil and accumulate these compounds in its tissues. These plants are able to tolerate higher amounts of toxic compounds than it's usual because of the broad range of detoxification mechanisms, which are taking place in these plants. After the root uptake, heavy metals may be chelated by phytochelatins, metallothioneins or other chelators and subsequently stored in vacuoles. Transport of metal ions and metal complexes between cells compartments is mediated by many specific transport proteins. Detoxification mechanisms of organic compounds involve transfomation, conjugation and store of these compounds in plant tissues.
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Study of physiological changes in plants under stress by zinc ions
Adam, Rostislav ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals are part of us life for many centuries. Some of them are for living organism neccessary, but in large amount they have toxic effects. So we should decrease amount of heavy metals in the Environment. We have many way to do it. A relatively new way are the phytoremediation. If we would use the phytoremediation, we should know, what they do in plants. We must use specific plants, which are tolerant to certain heavy metal. If we would select a suitable plant, we have to try, how heavy metals in soil solution are toxic to plants. Zinc is no expection, although it is important part of many proteins. In plants it make rusty leaves and reduct aboveground and root biomass production. In hydroponic experiment I investigated that mallow Malva verticillata was very sensitive to low additon of Zn(NO3)2. The toxic efect appeared in 2 weeks. In sorghum Sorghum bicolor zinc show expressive toxic effect at concentration 1 mmol/l. I studied six cultivars of Sorghum bicolor, DSM 14-535, Expres, Honey Graze BMR, Nutri Honey, Sucrosorgho 506 and Sweet Virginia. According EC50 I as- sessed that the most sensitive was Sucrosorgho 506 and very tolerant were Nutri Honey and Sweet Virginia. Cultivar Nutri Honey was characteristic. It had the highest ratio concentration in shoot to concentration in root. I studied...
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Mechanism of uptake of heavy metals and organic compounds by plants
Berkyová, Petra ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals and organic compounds represent a great problem for environment. Therefore, attention is paid to the development of techniques for removing these pollutants from the sites of pollution. One of the possibilities is that heavy metals and organic compounds are removed from soil by using fytoremediation. Fytoremediation uses the ability of some plant species to uptake toxic compounds from soil and accumulate these compounds in its tissues. These plants are able to tolerate higher amounts of toxic compounds than it's usual because of the broad range of detoxification mechanisms, which are taking place in these plants. After the root uptake, heavy metals may be chelated by phytochelatins, metallothioneins or other chelators and subsequently stored in vacuoles. Transport of metal ions and metal complexes between cells compartments is mediated by many specific transport proteins. Detoxification mechanisms of organic compounds involve transfomation, conjugation and store of these compounds in plant tissues.
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