Zinc (Zn) is a Transition Metal, and its uptake by plants is predominantly as a divalent cation (it carries a net positive charge). Zn is either bound to organic acids or occurs as the free divalent cation. Zn plays a role as a catalyst, and a structural role in the formation of enzymes and proteins involving Nitrogen, Oxygen and Sulfur. Zn is essential to, and plays a major role in a vast array of plant metabolic functions and pathways, and has been tied to at least 2,800 proteins involved in DNA replication and gene expression. The role of Zn in the formation of specific enzymatic functions and metabolic pathways, result in plant tolerance to environmental stress factors, as well as a peak genetic expression of cultivars.
Role in growth
Zn is also essential for many enzymes which are needed for nitrogen metabolism, energy transfer and protein synthesis.
The Zn plays very important role in plant metabolism by influencing the activities of hydrogenase and carbonic anhydrase, stabilization of ribosomal fractions and synthesis of cytochrome .
Plant enzymes activated by Zn are involved in carbohydrate metabolism,maintenance of the integrityof cellular membranes, protein synthesis,regulation of auxinsynthesis and pollen formation .
The regulation and maintenance of the gene expression required for the tolerance of environmental stresses in plants are Zn dependent .
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