Question

Choose the correct answer from the alternatives given.
The yellowing of leaves, called chlorosis, is usually caused by the deficiency of:

• A. sodium
• B. phosphorus
• C. magnesium
• D. calcium

Answer 1

The correct option is C magnesium

A magnesium-deficient crop will tend to have a pale overall colour. The earliest specific symptom of magnesium deficiency is interveinal chlorosis of older leaves. Chlorosis generally progresses to yellowing and necrosis of the oldest leaves. Therefore, without sufficient amounts of magnesium, plants begin to degrade the chlorophyll in the old leaves. This causes the main symptom of magnesium deficiency, interveinal chlorosis, or yellowing between leaf veins, which stay green, giving the leaves a marbled appearance.

So, the correct option is, 'Magnesium'.