The importance of the zinc element

The term "availability" is commonly used to describe the ability of plants to absorb nutrients from the soil. The availability of zinc to plants can be affected by factors such as total soil zinc content, soil pH, organic matter, soil temperature and moisture, root distribution, and rhizosphere effects. Soils with low zinc concentration are often deficient in zinc for crop production, such as Sandy soils are often deficient in available zinc. For example, Zn deficiency in plants grown in acidic soils is generally associated with low total Zn concentrations. These cases of zinc deficiency are related to absolute zinc deficiency rather than zinc availability.
Total soil Zn concentration in calcareous and non-calcareous soils is often similar. However, zinc deficiency is often reported for calcareous soils. Calcareous soils with moderate to high organic matter content (more than 15 g organic carbon per kg soil) are zinc deficient due to high levels of HCO 3 - in the soil solution. In alkaline soils with low zinc reserves, increasing the application of zinc increases the concentration of zinc in plants and reduces deficiency symptoms.
Soil organic matter content is another factor that contributes to zinc deficiency in plants. Due to increased Zn uptake by ligands and organic components, Zn availability to plants is often low in soils with high organic matter content. A sufficient level of organic matter increases the solubility and diffusion rate of zinc in the soil.
Other factors that play a role in zinc deficiency are low soil moisture and low temperature. Soil moisture affects the supply of nutrients by disrupting diffusion to the root surface. Given that Zn release in soil is highly dependent on soil moisture, plant Zn levels may be compromised in semi-arid and arid regions where soils are typically water-deficient for long periods during the growing season. Based on this, in calcareous soils with zinc deficiency, the reduction of wheat yield is more intense in dry conditions than in wet conditions. Therefore, the decrease in zinc solubility and low absorption of zinc in soils with poor drainage is due to the simultaneous precipitation of zinc with soluble iron and aluminum in the soil. Early in the growing season, Zn deficiency occurs when the soil temperature is still relatively low and subsequently decreases as the temperature increases. Low soil temperature often increases the incidence and severity of zinc deficiency symptoms.
The interaction of zinc with other elements reduces the availability of zinc and affects its absorption, distribution and utilization in plants. These interactions are mainly due to the effect of other cations on the rate of uptake by plant roots rather than their effect on availability or forms. The competition and interaction of zinc with phosphorus and nitrogen are the most important and widespread interactions of zinc in soils with limited reserves of zinc and phosphorus or nitrogen. This element must be in balance with other required elements in the soil, so that high levels of phosphorus in the soil cause zinc deficiency, on the other hand, with a decrease in the amount of nitrogen due to weakness in the plant, zinc absorption also decreases. Copper also competes with zinc due to the same absorption mechanism. On the other hand, the addition of magnesium can also increase the absorption of zinc. High levels of arsenic in old gardens also prevent the absorption of zinc. It has been determined that this element must be in balance with manganese.