Macroelements for Plants
Macroelements include mineral elements whose concentration in the human body ranges from 10–1 to 10–2%.
In plants, macroelements contribute to the integrity of cell membranes, facilitate photosynthesis, stabilize the water regime, increase the strength of plant tissues, participate in nitrogen and carbohydrate metabolism, as well as in the processes of respiration and oxidative phosphorylation, providing plant tissues with energy.
Macroelements include potassium, calcium, silicon, magnesium, sodium, sulfur, phosphorus, and chlorine.
- Potassium is one of the three primary elements (along with phosphorus and nitrogen) essential for plant life and development. Optimal fundamental functions of the plant organism are achieved only with sufficient potassium nutrition. In plants, it acts as a stabilizer of the water regime;
- calcium promotes the integrity of cell membranes and the water-holding capacity of protoplasm, participates in the construction of the plant cell wall, enhances the strength of plant tissues, and contributes to increased plant endurance;
- silicon affects stem strength, resistance to lodging, flowering intensity, and ovary energy. It increases phosphorus uptake by plants due to the enhanced solubility of soil phosphates under the influence of silicic acid;
- magnesium in the plant organism is a constituent of the photosynthetic pigment chlorophyll, participates in the accumulation of solar energy during photosynthesis, in phosphorus transport, and in carbohydrate metabolism, and influences the activity of redox processes;
- sodium regulates carbohydrate transport in the plant organism. It is crucial for the transmembrane transport of substances, being a component of the so-called sodium-potassium pump (Na+/K+). Sufficient sodium supply increases the winter hardiness of plants;
- chlorine participates in energy metabolism within the plant organism, positively influences oxygen uptake by roots, prevents the penetration of fungal infections, and takes part in oxidative reactions in plants;
- sulfur participates in nitrogen and carbohydrate metabolism, respiration, and lipid synthesis in the plant organism. The majority of sulfur in plants is found in proteins (as a constituent of the amino acids cysteine, cystine, and methionine) and other organic compounds such as enzymes, vitamins, as well as mustard and garlic oils;
- phosphorus, along with potassium and nitrogen, is one of the three elements absolutely essential for plant life and development. The physiological significance of phosphorus as an energy source is determined by its inclusion in various organic compounds – nucleic acids (DNA and RNA), nucleotides (ATP, NAD, NADP), nucleoproteins, vitamins, and many others that play a central role in metabolism.