Question

The first symptom of chlorosis in Mg deficiency is:

• A. Young leaves fall down first followed by the old leaves
• B. Old leaves drop down followed by young leaves
• C. Leaf fall
• D. Formation of chromoplasts

Answer 1

The correct option is B Old leaves drop down followed by young leaves

The first symptom of chlorosis in Mg deficiency is the dropping of the old leaves followed by the young leaves. For elements that are actively mobilised within the plants and exported to young developing tissues, the deficiency symptoms tend to appear first in the older tissues. For example, the deficiency symptoms of nitrogen, potassium and magnesium are visible first in the senescent leaves. In the older leaves, biomolecules containing these elements are broken down, making these elements available for mobilizing to younger leaves.

So, the correct answer is 'Old leaves drop down followed by young leaves'