Zinc transfer in the plant
Zinc transfer in the plant:
In plants, zinc is transferred from root to stem and leaf by xylems. Zinc transfer from older leaves to younger leaves also occurs during the growth of seeds.
Zinc in the soil:
The total content of zinc in the soil can range from 10 to 300 mg/kg.
The pH of the soil is very effective in solubility. As, the higher the soil alkalinity (calcareous), the more difficult the absorption of zinc for the plant. The presence of compounds such as hydroxide and carbonate ions causes the formation of zinc hydroxide and zinc carbonate, reducing the zinc solubility and absorption for the plant.
Moreover, high levels of phosphorus can cause zinc deficiency, since in addition to reducing solubility, it prevents root growth and the plant will not be able to access the zinc sources in the deeper areas of the soil.
Excessive amounts of copper ion reduces plant access to zinc as well, as absorption of both ions takes place with the same mechanism. Since the copper and zinc ion adsorption mechanisms are similar, excessive copper ion level can be the cause of zinc deficiency in the plant.
Using zinc sulfate in saline soils with high pH and calcareous soils can be very beneficial. Because zinc sulfate can reduce pH and thus control it, hence facilitating the absorption of nutrients for the plant.
Most of the zinc in the soil is inaccessible to the plant due to its specific position, and the use of the external source of zinc is of particular importance for soil fertility.