Question

When chemical fertilisers are given to plants, the soil is to be thoroughly watered otherwise the plants die because of

• A. Toxic effects of chemical fertilisers.
• B. Plasmolysis due to high concentration of fertilisers.
• C. Failure of physiological process like photosynthesis and respiration.
• D. None of the above.

Answer 1

Answer: (B)

Plasmolysis due to high concentration of fertilisers.

If excess fertilizer is added to the soil then due to a high concentration of chemicals the soil will become hypertonic as compared to the cell sap of the roots of the plant. Thus, the water will flow out of the roots through the process of exosmosis. The roots will become plasmolysed and excessive loss of water may kill the plants. If the soil is thoroughly watered then the concentration of solvent will also become equal to the concentration of solute and there will not be concentration gradient for osmosis and plant will not get killed.

So the correct answer is 'Plasmolysis due to the high concentration of fertilisers'.