Calcium, a divalent cation has numerous critical functions for plant growth that have been identified in plant physiology and molecular biology, for example pectin cell wall binding and strengthening, root elongation ceases within a few hours in the absence of calcium. Shoot elongation growth is mainly determined by calcium concentration and auxin action, pollen tube growth is dependent on the presence of calcium and growth of tube is chemotropically controlled. Cation - anion balance and osmo-regulation, membrane stabilization, low tissue content in fleshy fruits increase the loses caused by senescence, fungal infection and various storage disorders and calcium as a second messenger.