Question

(a) Moderate decrease or increase of micronutrients causes deficiency and toxicity symptoms respectively.
(b) Excess of manganese causes toxicity of iron, calcium and molybdenum.
(c) A macronutrient is said to be toxic when present below a critical concentration.

• A. Only (a) is correct
• B. Only (b) is correct
• C. (b) and (c) are correct
• D. (a) and (c) are correct

Answer 1

The correct option is A Only (a) is correct

A macronutrient is said to be toxic when present above a critical concentration. Moderate decrease of micronutrients causes deficiency in plants and excessive intake of minerals or micronutrient causes toxicity. Excess of manganese causes deficiencies of iron, calcium and molybdenum.