Soil Fertility and Nutrient management (1+1)

Effect of salinity on crop growth

Excess amount of soluble salts affects the plant in the following ways;
Water availability to plants decreases: with increase in salt concentration of the soil the osmotic pressure of the soil solution increases and plants are not able to extract water as easily as they can from the soil. Therefore, EC (e) of the soil increases the water becomes less available to the plant even though the soil may contain water and appears quite moist. Due to high osmotic pressure water comes out of the plant which is called reverse osmosis or plasmolysis. The plant show wilting symptoms which referred as physiological drought.
Specific Toxic effect of ions: Higher concentration of individual ions in the root environment or in the plant may prove toxic to the plant or may retard the uptake (absorption) and metabolism of the essential plant nutrients and thus affect the normal growth of the plant. Antagonism between Cl- and H2PO4-, C1- and NO3-, C1- and SO42- and Na+ and K+ may disturb the normal nutrition of plants.