Question

Describe the utility of nitrogen for plants and the symptoms caused by a deficiency of nitrogen?

Answer 1

Nitrogen is used in the synthesis of amino acids, proteins, DNA, RNA, chlorophyll and other organic compounds. 

• Nitrogen regulates respiration and growth of plants.
• It is required more in actively growing cells and buds. 

Deficiency Symptoms: 

• Chlorosis of leaves occurs first in old leaves and later on in young leaves.
• Due to the degradation of chlorophyll, anthocyanin pigment is formed and the leaves appear pinkish in colour.
• Rate of cell division and rate of protein synthesis is reduced and plants become stunted due to reduced growth.

Answer 2

Symptoms include poor plant growth, and leaves that are pale green or yellow because they are unable to make sufficient chlorophyll. Leaves in this state are said to be chlorotic. Lower leaves (older leaves) show symptoms first, since the plant will move nitrogen from older tissues to more important younger ones.