NEET BIOLOGY

Detailed explanation-1: -So the correct answer is ‘Potassium’.

Detailed explanation-2: -Chlorosis at leaf margins is a typical symptom of potassium (K) deficiency, but inappropriate application of K with other nutrients often masks symptoms of K deficiency.

Detailed explanation-3: -Common symptoms of a potassium deficiency are: Chlorosis (yellowing of leaf tissue) between leaf veins. Purple spots on the leaf underside.

Detailed explanation-4: -In plants, mottling usually consists of yellowish spots on plants, and is usually a sign of disease or malnutrition. Many plant viruses cause mottling, some examples being: Tobacco vein mottling virus.

Detailed explanation-5: -A common cause of chlorosis is a deficiency of iron or manganese, both of which are present but unavailable in high pH soils (pH>7.2). Iron and manganese are needed by plants to form chlorophyll and to complete photosynthesis.