Question

Magnesium deficiency in crop plants leads to A. Chlorosis of older leaves, B. Interveinal chlorosis, C. Dead necrotic patches, D. Premature leaf fall.

• A. A Only
• B. B and C Only
• C. B Only
• D. C and D Only

Hint:

Magnesium deficiency mainly causes interveinal chlorosis, and severe deficiency may produce necrotic patches.

Answer 1

The Correct Option is B

Concept:
Magnesium is an essential plant nutrient and is a central component of chlorophyll. Therefore, its deficiency mainly affects leaf greenness.

Step 1: Role of magnesium.
Magnesium is required for chlorophyll formation and photosynthesis.

Step 2: Deficiency symptom.
When magnesium is deficient, leaves show interveinal chlorosis. This means the area between veins becomes yellow while veins may remain green. \[ B \text{ is correct} \]

Step 3: Severe deficiency.
In severe cases, chlorotic areas may develop dead necrotic patches. \[ C \text{ is correct} \]

Step 4: Select correct combination.
The correct symptoms from the given options are: \[ B \text{ and } C \] \[ \therefore \text{Correct Answer is (B)} \]