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NH4 + is one of the major inorganic forms of nitrogen taken up by plant roots from the soil. The response of plants to NH4 + depends on a number of factors - especially its concentration in the rhizosphere or the availability of other ions such as K+ or NO3 - . In the case of a low nitrogen availability in the rhizosphere, NH4 + positively affects the growth of the root system. In the NH4 + -rich area of rhizosphere, local stimulation of lateral root branching may occur to enhance effective acquisition of the present nitrogen source. A sensor that perceives NH4 + and induces this response of root system response is the high affinity ammonium transporter AMT1;3. With excess NH4 + , the growth of the whole plant is inhibited and this phenomenon is called ammonium toxicity syndrome. This syndrome is the result of the interaction of NH4 + with various processes in the plant and induced K+ deficiency is one of the most important signs of this syndrome. NH4 + and K+ directly interfere with each other during uptake. NH4 + enters the plant through K+ channels and also inhibits the expression of the high affinity K+ transporters, thereby significantly reduces its uptake. NH4 + and K+ interference is one of the main topics that this bachelor thesis focuses on. It also summarizes mechanisms of uptake and... |
