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Even though nitrogen is a necessary element for life, too much of it in water can have negative effects on aquatic ecosystems and endanger human health. Agricultural runoff, where fertilizers containing nitrogen compounds can seep into rivers, lakes, and groundwater, is one of the main sources of nitrogen in water.
Nitrogen is a major constituent of several of the most important plant substances. For example, nitrogen compounds comprise 40% to 50% of the dry matter of protoplasm, and it is a constituent of amino acids, the building blocks of proteins. [9] It is also an essential constituent of chlorophyll. [10]
Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...
For example, the detection and measurement of gene expression has enabled researchers to determine which genes are up-regulated in the plant and fungus under various nitrogen conditions. Another important tool is the use of the nitrogen isotope [[15 N]], which can be distinguished from the more common 14 N isotope. Nitrogen-containing compounds ...
Although nitrogen makes up most of the atmosphere, it is in a form that is unavailable to plants. Nitrogen is the most important fertilizer since nitrogen is present in proteins (amide bonds between amino acids), DNA (puric and pyrimidic bases), and other components (e.g., tetrapyrrolic heme in chlorophyll). To be nutritious to plants, nitrogen ...
A biofertilizer is a substance containing living micro-organisms which, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. [1]
Plants that contribute to nitrogen fixation include those of the legume family—Fabaceae— with taxa such as kudzu, clover, soybean, alfalfa, lupin, peanut and rooibos. [45] They contain symbiotic rhizobia bacteria within nodules in their root systems, producing nitrogen compounds that help the plant to grow and compete with other plants. [64]
It is selectively taken up by plants, so there are a variety of possible roles in plant metabolism. [44] There is limited medical use. [11] Inhibits iron uptake and metabolism in a variety of plants and bacteria. [44] germanium: 32: 2a: Some plants will take it up, but it has no known metabolic role. [11] Some salts are deadly to some bacteria ...