Calcium is taken from the environment. In plant cells and tissues to be present in ionic form and the form of inorganic and organic combinations.
Calcium cells fulfills a structural and functional role.
Excess calcium green-sickness cause plant, due to the solubility and absorption of mineral compounds of iron, manganese.
Sulfur is present in the soil as organic and mineral.
Organic sulfur is the most important reserves of ground mineralization and progress to a more or less quickly depending on the activity of microorganisms.
Iron must be present in the soil in a form assimilable otherwise occurs deficiency manifested by green-sickness. Iron deficiency is associated with a yellowing of leaves.
Of all the elements, potassium is found in greatest quantity in plants, especially the young, in the form of inorganic salts.
Potassium deficiency is felt more strongly on soils with high salt content of calcium and magnesium and poor aeration. External symptom of potassium deficiency is the leaf color change, that the appearance of brown spots, especially near the extremities of the leaf.
Sodium plays a well defined role in vascular bands and fibers that support the plant tissue.
Halophile plants, adopted an environment with high concentrations of sodium, this element is necessary for growth, give a better color of the leaves, increases disease resistance.
It is found in soil. Magnesium absorption by plants is conditioned by three main factors: the amount of land accessible, magnesium interactions with other elements and requirements of the plant. Insufficient magnesium produces necrosis of leaves. Magnesium accumulate in seeds, formed with phosphoric acid, fitina.